This paper investigates measurement methods of frequency converters' phase noise transfer function. The typically used instrumentation and setups quantifying absolute and residual phase noise are discussed first. We identify the possibility of extending the functionality of single-channel signal source analyzers by estimating the device's transfer function. The test results of proposed technique are given.
In this paper, we propose that optical Bloch oscillations-Zener tunneling is observed in stacked metal fishnet waveguide arrays. The analogy of Bloch-Zener tunneling, which is the dynamic behavior of electrons in solid under an external field, is achieved. The spoof surface plasmon polaritons by structured surface and near fields coupling between adjacent layers of metal waveguide arrays induce the optical Bloch-Zener tunneling. The effect can be predicted and demonstrated by the dispersion relationship.
The finite element method is one of the most commonly used numerical methods for solving Maxwell's equations in the computer-aided design of microwave components. However, its accuracy comes at the price of the high computational cost and therefore fast optimization involving full-wave finite element simulations is still a big challenge. One of methods to speed up the optimization process is parametrized model order reduction (PMOR). In this approach the initial projection basis is generated only once, in the offline phase, and then it is reused in subsequent optimization steps for any set of geometry and material parameters. In this work we show how to improve the quality of PMOR by enriching it with a few vectors that are computed by applying a few iterations of a preconditioned conjugate solver with deflation.
This paper proposes a combination of the field matching technique, finite element method and generalized impedance matrix, the main idea of which is to reduce the computational domain by surrounding a scatterer with the smallest convex shape and applying the field matching technique. This approach can be applied for arbitrary shaped scatterers and types of materials and allows for the reduction of the computational domain. In order to verify the validity of the method, several examples have been investigated and compared with other numerical techniques.
In this paper, concepts of fractional-order (FO) derivatives are analysed from the point of view of applications in the electromagnetic theory. The mathematical problems related to the FO generalization of Maxwell's equations are investigated. The most popular formulations of the fractional derivatives, i.e., Riemann-Liouville, Caputo, Gruenwald-Letnikov and Marchaud definitions, are considered. Properties of these derivatives are evaluated. It is demonstrated that some of formulations of the FO derivatives have limited applicability in the electromagnetic theory. That is, the Riemann-Liouville and Caputo derivatives with finite base point have a limited applicability whereas the Gruenwald-Letnikov and Marchaud derivatives lead to reasonable generalizations of Maxwell's equations.
The problem of electromagnetic (EM) wave scattering for a homogeneous material supplemented by a set of thin wires is studied by an asymptotic method. The electrical components of the full EM field are presented in an explicit form. The refraction coefficient (RC) of resulting inhomogeneous material is derived as result of solving some auxiliary integral equation. The computational results testify that new inhomogeneous material is characterized by specific RC that can acquire the negative values.
In this contribution, a new genetic-algorithm-based method of searching for roots and poles of a complex function of a complex variable is presented. The algorithm employs the phase analysis of the function to explore the complex plane with the use of the genetic algorithm. Hence, the candidate regions of root and pole occurrences are selected and verified with the use of discrete Cauchy's argument principle. The algorithm is evaluated in electromagnetic benchmark that successfully solves the eigenvalue problem determining the propagation of surface waves along a spatially dispersive graphene sheet. The numerical results show that possibility to find all roots and poles of the function may be limited by the initial population size, especially when the search region is large and roots and poles are located close to each other.
This paper proposes a new calibration method for vector network analyzers, and the method uses one thru calibration standard and two short calibration standards. We name this new calibration method "Thru-Short-Short" (TSS) calibration method. The algorithm of the proposed method is derived in this paper in detail. At the same time, the experimental results are used to prove the accuracy of the TSS calibration method. When we calibrate the vector network analyzer with this method, the fixtures at both ends are fixed, and they do not need to be moved. It is very convenient for the scenarios that the fixtures are not easy to move. The validity and accuracy of the proposed method are verified by experimental results of measuring the permittivity of a slab of Teflon.
Work presented in this paper is a part belonging to a micro-Doppler detection project. Global aim of the project is to develop processing algorithms and waveform designs suitable for the human-originating micro-Doppler detection. Purpose of this work was to develop an auxiliary tool for the analysis. To simulate signals and processing properties in terms of micro-Doppler detection, a proper model of a scattering object, with particular emphasis on the properties of human tissues, was needed.
In this paper, algorithms for simulation of the wave propagation in electromagnetic media described by fractional-order (FO) models (FOMs) are presented. Initially, fractional calculus and FO Maxwell's equations are introduced. The problem of the wave propagation is formulated for media described by FOMs. Then, algorithms for simulation of the non-monochromatic wave propagation are presented which employ computations in the time domain (TD) and the frequency domain (FD). In the TD algorithm, the electromagnetic field is computed as a convolution of an excitation with Green's function formulated based on an improper integral and the Mittag-Leffler function. On the other hand, the FD algorithm transforms an analytic excitation to FD, executes multiplications with phase factors, and finally transfers back result to TD. This algorithm involves elementary functions only, hence, computations are significantly faster and accurate with its use. However, applicability of the FD algorithm is limited by the sampling theorem. Numerical results and computation times obtained with the use of both algorithms are presented and discussed in detail.
In future 5G mobile networks the radio over fiber (RoF) links will gain wider application due to its simplicity, flexibility and elasticity. In these links single drive Mach-Zehnder modulators are used for intensity modulation. However, these modulators produce not only intensity modulation but also incremental phase modulation which is a challenging problem because that effects the signal transmission. The other challenging problem is caused by fiber dispersion. Therefore fading of the detected signal is obtained at specific fiber lengths. However, applying combined double intensity and phase detection the received signal variation is reduced significantly. The transmission of digital signals is also influenced by fiber dispersion causing pulse broadening and this way inter-symbol interference which limits the bit rate. In this paper the modulation and propagation problems and their effects on signal transmission quality are investigated achieving this way optimum solution.
In this article, a new meta-heuristic method of searching for roots and poles of a complex function of a complex variable is presented. The algorithm combines an efficient space exploration provided by the particle swarm optimization (PSO) and the classification of root and pole occurrences based on the phase analysis of a complex function. The method initially generates two uniformly distributed populations of particles on the complex plane and extracts the function phase in a position of each particle. By collecting phase samples, the candidate regions of root and pole occurrences are selected. Then, the second and subsequent populations iteratively explore candidate regions and decrease their size. Because subsequent swarms are generated globally during the iterations, an area outside a candidate region is thoroughly explored, eliminating possibility of root or pole omission. The algorithm is verified in electromagnetic benchmark that solves the equation determining surface waves on a microstrip antenna. The numerical results show that the algorithm is able to solve multimodal problems quickly even with a small initial population and a small number of generated swarms.
This paper overviews the process of prototyping of corporate feeds for excitation of linear arrays of low sidelobe broadside sum patterns. Although the corporate feeds of interest produce non-uniform in-phase excitation tapers at their outputs, they comprise only equal-split power dividers and thus shorten the feed implementation stage, simplify the corporate feed composition, and reduce sensitivity of the feed elements to tolerances of manufacturing and material parameters. A summary of the selected results with the emphasis on low sidelobe levels is presented. The levels are computed using the array factor and provided for feeds driving linear arrays of up to thirty elements. It is should be emphasized that the array characteristics at the feed prototyping stage are irrelevant to the feed-array implementation technology and, in this sense, are similar to characteristics of filters' prototypes. The outline of the dedicated software package developed in Matlab used for feed prototyping is overviewed. An example of feed implementation in microstrip technology with electromagnetic simulations for the upper part of the K-band is presented. The considered class of corporate feeds as well as the feed prototyping tool considered in this work can contribute to the development of cost-and performance-efficient communication solutions for sub-mm wave and mm-wave frequencies.
In this paper a novel design of broadband reduced-length directional coupler for planar and MMIC applications has been presented. The proposed component utilizes two indirectly coupled-lines sections realizing the same coupling coefficient connected with uncoupled transmission-lines. To verify the correctness of the proposed design method, a 3-dB planar directional coupler for 1 GHz center frequency has been designed, fabricated, and measured. Moreover, a monolithic version of the considered solution has been designed for fabrication in the monolithic OMMIC D01PH GaAs technology, operating at 24 GHz center frequency.
In the paper, outputs of the sensitivity analysis performed for a 60 GHz circularly polarized antenna array is presented. The analysis identifies dimensions and positions of coupling slots between layers, dimensions of patches and the width of waveguides as critical. Precision of manufacturing technologies has to be better than 0.1 mm to obtain acceptable parameters of the whole array.
In this paper a rotating coupler is presented that can be used for signal transmission on fast rotating shafts. Rotating couplers may be necessary especially in big industrial halls where, due to more and more transmitters around 2.45 Ghz, the industrial, scientific and medical (ISM) band of many radio standards, the channel can be too crowded to reliably transfer safety critical information. The concept of the here presented coupler is to be low-cost and splitable that it can be attached around a shaft even without the disassembly of the entire machinery.
We investigated operation of microwave sensors for detection of objects floating on a river. Three types of sensors with different operation principle were chosen for testing: FMCW perimeter radar, microwave barrier and monostatic Doppler detector. During tests, selected objects (boats, packages and swimmers) repeatedly flowed across a 45-m wide river. The purpose of the study was to determine the probability and range of detection for various external conditions and the detector-object distances.
Nowadays indoor localization is getting more and more attention as there is a considerable growth in the interest for the indoor location-based services (LBS). There are several different techniques that allow for the calculation of the position of objects and people inside the buildings. Methods utilizing measurements of the received signal strength (e.g. WiFi or BLE based) are most common but provide accuracy of roughly 2-3 meters. Recently, ultrawideband (UWB) technique is more often being considered for the indoor localization. It relies on the measurements of the time of arrival of received signals and allows for the calculation of the position with errors in the range of only dozens of centimeters. However, in order to work correctly, UWB-based systems require strict synchronization between the anchors that form the infrastructure. In the paper a novel method of wireless synchronization utilizing two reference nodes is presented. Synchronization method is described along with the explanation of the transmission scheme and discussion on the results of the performed experimental verification.
A planar antenna is designed to replace complex structures of many rat-races and 90° hybrids used in conventional target detection antennas. The proposed antenna has 2 x 2 microstrip patch antenna arrays with dual feeding to radiate symmetric polarizations in the 9.375 GHz (X-band). The sum pattern with circular polarization is implemented through a sequence feeding at port 1. The simultaneous feeding of port 2 radiates a difference pattern in all polarizations. Thus, a target detection antenna is designed with features that have fewer ports than the conventional monopulse antennas. The proposed antenna is compact, planar, and has a simple comparator circuit and equal sum and difference levels.
Single Frequency Networks are a popular solution in modern digital audio and television system networks for extending effective coverage, compared to their traditional single-transmitter counterparts. As benefits of this configuration appear to be obvious, this paper focuses on the exact analysis of, so called, SFN gain - a quantitative effect of advantage in terms of the received signal strength. The investigations cover the following aspects: the histogram analysis of SFN gain values and the SFN gain as a function of distance from the SFN geometrical distance. The analyses conclude with an observation that the most noteworthy contribution from the operation in the single frequency mode is observed on the far edges of the networks, whereas the least one close to the transmitters
Active Electrically Scanned Array (AESA) requires a diagnostic system that can consists of a set of external antennas for calibration of Transceiver Modules (TRM). In this paper, a microstrip patch antenna with wide beamwidth for such a system is presented. The manufactured antenna exhibits a 180º 6-dB beamwidth in C-band with matching better than -10 dB over a 10% bandwidth. It is shown that the use of the proposed antenna results in a reduced dynamic range of diagnostic coupling between the antenna and TRMs compared to antennas with the directivity of order of several dBi, thus the number of diagnostic antennas can be decreased and they can be placed closer to radar aperture boundaries. Furthermore, it is demonstrated that a low level of back radiation of the antenna leads to a diminished parasitic influence of radar construction elements on the desired coupling coverage.
The study of Class E amplifier operation modes with shunting filter as well as those of derived Class E/F3 and EF amplifiers with 0.33 duty ratio was performed. The goals of the experimental study was the reduction of maximum (over signal period) transistor drain voltage and reduction of the harmonic content in amplifier output. The normalized drain voltage in the range 2.2-2.35 at 90% efficiency was observed. The results can be used for high-efficiency amplifier design in the form of Integrated Circuits.
On the base of 2-plane discontinuity in microstrip transmission line the output networks for class-E/F amplifier with harmonic control are presented. The output network transforms high resistance of load into a low load resistance at MOSET drain. The harmonic filters are realized using coupled slot resonators of complex shape in ground plane of microstrip transmission line. Using this solution, the two output networks were designed and investigated: with control up to 3-rd, and up to 4-th harmonics inclusive. In the amplifier with 4-th harmonic control the drain voltage has flat waveform, which significantly increases transistor utilization factor. Efficiency of the both simulated power amplifiers at the operating frequency of 2.14 GHz was more than 80% at the output power level of 5.3-6.0 W.
Monopulse Comparator is one of the core components in development of RF front-end of the tracking radars and therefore widely employed in active phased array radars. Thus, active phased array system are progressively becoming the norm for airborne radars imposing stringent requirement on operation over a wide range of frequencies The proposed design employed four rat race couplers (180° hybrid coupler) to devise the monopulse comparator network and to exploit microstrip technology to realize the network. In this paper, an X-band Monopulse Comparator Network from 8 GHz to 11 GHz is realized on RT Duroid 6002 using microstrip transmission line technology. The design of the monopulse comparator network is modeled and simulated in ANSYS HFSS. The proposed monopulse comparator network achieved VSWR ≤1.6, and isolation values better than 20 dB for almost the entire frequency band.
A Ka-band compact 8-way power-combining amplifier is proposed by using parallel traveling-wave power divider with coplanar-arms magic-T. The coplanar-arms waveguide magic-T is applied to be the first dividing stage with compact size and great isolation. Two parallel dual-probe-coupling two-way traveling-wave power divider are applied to form a compact 8-Way divider with the measured insertion loss less than 2dB from 27-33.5GHz. The proposed divider is applied to a power combining amplifier. Its measured output power at 1dB gain compression (P1dB) is higher than 12.5 Watts, power-combining efficiency is from 74% to 93% from 27-33.5GHz. The whole size of the proposed structure is 60mm×40mm×25mm.
A concept of electrically small antenna for BeiDou BD2 B3 Chinese navigation satellite system was developed and studied. Three main miniaturized techniques: antenna loading by using high permittivity materials, making some part of antennas virtual by using ground planes and short circuits, and optimizing geometry have been employed in the design. Antenna performance was examined by experiments giving very promising results.
The main goal of the tutorial is to provide the audience with a bouquet of optimization techniques to address different challenging waveform design problems in classical and emerging Multiple Input Multiple Output (MIMO) radar systems, under practical constraints.
Waveform design plays a key role in enhancing classical radar tasks including target detection and parameter estimation. Further, waveform design is a key enabler of the emerging paradigm on joint radar-communications. Different applications warrant different performance metrics; this coupled with the advent of MIMO radar makes the waveform design more challenging. Particularly, in the emerging scenario of self-driving automotive applications, towards enhancing safety and comfort, high spatial resolution is achieved using the colocated MIMO virtual array by maintaining orthogonality between the transmit waveforms. Further, waveform diversity can also be used to obtain low-probability-of-intercept (LPI) radar properties. Nevertheless, the static use of a fixed waveform reduces efficiency due to limited or no adaptation to the dynamic environment as well as vulnerability to electronic attacks highlighting the need for multiple and diverse waveforms exhibiting specific features.
In this context, the tutorial focusses on key applications and highlights a variety of optimization approaches including coordinate descent (CD) and majorization minimization (MM), dealing with important applications in radar including 1) enhancing angular resolution using sets of orthogonal sequences, 2) SINR enhancement with joint design of space-time transmit and receive weights, 3) enabling a joint radar-communications paradigm through the transmit waveform design. To further bring the optimization closer to implementation and early adaptation in systems, practical constraints, such as finite energy, unimodularity (or being constant-modulus) and finite or discrete-phase alphabet are included in the optimization problem as constraints. The diversity of design metrics and signal constraints lays the groundwork for many interesting research projects in waveform optimization.
While several seminal works have been published, a few previous "IRS" tutorials have focused on the optimization algorithms dealing with the various applications of active sensing. After attending the tutorial, participants will be able to understand: • An overview of relevant theoretical bases and algorithms from optimization theory considered in the state-of-the-art waveform design. • Current challenges and design criteria associated with waveform design in classical and emerging radar systems. • Key hardware constraints of the practical radar systems and their consideration in the optimization formulation. • An insight into formulation of waveform design optimization problems in modern radar systems and a few approaches towards finding a solution.
Tutorial outline:
We will present this tutorial in two slots and different parts as listed below:
• Part I: A brief review of optimization principles, active sensing scenarios and problem formulation (50 mins): This part begins by describing and illustrating principles of convex and non-convex optimization theory. Next, we consider casting various design problems in active sensing systems. More precisely, we address several scenarios like PSL/ISL minimization for classical radar systems, designing sets of orthogonal sequences for emerging MIMO radar systems, joint sensing and communications and so on. In this context, emphasis on the objective functions and constraint sets of the associated problems. • Part II: CD optimization framework for transceiver design (50 mins): The CD based methods are intuitively appealing and simple to implement, yet they have shown powerful performance in emerging large-scale signal processing, machine-learning, regression, compressed sensing, and radar applications. The idea behind CD is not to tackle the original problem directly, but by iteratively optimizing it over a single coordinate, while keeping the other coordinates fixed. The most important advantage of the CD method is that the minimization of a multi-variable function can be achieved minimizing it along one direction at a time, i.e., solving a set of potentially simpler uni-variate sub-problems in a loop. Using this framework, we illustrate how to apply CD method on the design problem introduced in the previous part.
• Part III: Waveform optimization in mm-Wave sensing and communications (40 mins): In this part we introduce the driving factors for mm-Wave spectrum sharing, low-cost design and differences with respect to cm-Wave joint sensing-communications. The need for synergetic waveform design accomplishing radar and communication tasks will be highlighted. Focussing on the automotive scenario, different topologies and related challenges on waveform design will be presented. Waveform design based on aforementioned methodologies will be presented and the gains achieved will be discussed. • Part IV: MM optimization framework for waveform design (40 mins): The MM based methods introduced for various transceiver design problems in active sensing systems will be presented in this part. The idea is to address a difficult optimization problem indirectly, by finding a surrogate function that makes the optimization problem "easy" (or, in any case, easier than the directly solving the original problem). We illustrate tricks for finding surrogate functions and the key aspects in this framework through a variety number of examples. • Part V: Summary and open challenges (20 mins): The aforementioned optimization methodologies have gained growing popularity in various applications. Some of these will be mentioned, and a summary of the introduced methods as well as the remaining challenges will be discussed in this part.
In this paper characterization of ferroelectric ceramic-polymer composites at microwave frequencies is presented. Tested materials are composed of barium strontium titanate (BST) and polyvinylidene fluoride (PVDF). The influence of three different shapes of ceramic particles is investigated. Measurement setup for determining the permittivity and tunability is described. Results show that the rod-like BST/PVDF composite has the best dielectric constant and tunability at 10 GHz with a value of 13 and 9% at 6 V/µm, respectively.
In this study, S11 at the front surface of the sample was measured in the frequency band of 0.50 to 3.0 GHz with various liquids in the jig after S11 calibration using SOM (short, open and reference material) conditions. The dielectric constant of the liquids was estimated from the above S11 based on 1. an inverse problem approach involving comparison with the S11 value calculated using electromagnetic analysis (known as the mode-matching method), and 2. an estimation formula involving comparison with termination associated with short, open and reference-material conditions. The Debye dispersion equation for calculation of methanol's complex permittivity was corrected from the results. The dielectric constants of various liquids were estimated using a formula for comparison with three reference materials (pure water, methanol and air) using methanol after dielectric-constant correction. The effectiveness of the proposed method was verified by comparing the above estimated values with otherwise obtained outcomes. Moreover, the S11 value of the jig was calibrated with short, open and another reference material (methanol) conditions after complex permittivity correction of methanol. The estimation results for the dielectric constant of pure water and similar after calibration were also compared with the above estimation values, and the reversibility of the proposed estimation method was verified. Favorable agreement of values estimated with each method was observed, indicating the validity of the proposed dielectric measurement procedure.
Ferromagnetic linewidth, g-factor and magnetic anisotropy measurements of mono- and polycrystalline yttrium iron garnet (YIG) spheres performed in a subwavelength cavity are reported, covering a frequency range of up to 28 GHz. Two factors influencing the apparent linewidth have been analyzed: the influence of the share of energy stored in the magnetic field to the total electromagnetic energy in the resonant system and conduction losses in the cavity walls. Additionally, two-port rectangular resonant cavity linewidth measurements at a few modes have been conducted. Good agreement between the two methods has been found. In the polycrystalline samples, the existence of the Buffler peak was identified, which is a non-Gilbert-type increase in the ferromagnetic linewidth vs. frequency dependence.
We investigate the impact of meniscus shaping the top surface of liquid samples tested in a semi-open cell applied to broadband permittivity measurements. We calculate the scattering parameters of the samples with flat and distorted surfaces using electromagnetic simulations done up to 18 GHz. The data are then processed using different methods for determining the permittivity. We compare the results of the Nicolson-Ross-Weir technique and our new meniscus removal method. This comparison clearly shows that the meniscus removal approach brings about smaller errors than the established NRW technique, particularly at higher microwave frequencies.
Low-loss dielectric laminates that are routinely used in manufacturing of printed circuit boards (PCBs) are known to be anisotropic. The in-plane and the out-of-plane components of the dielectric permittivity have been so far typically determined using several approaches. In this paper we performed measurements of both components of complex permittivity of selected isotropic and anisotropic laminar materials employing a combination of a few split-post dielectric resonators (SPDRs) and one cylindrical cavity supporting a few TM0n0 modes resonant frequencies of 2.45 GHz. No similar characterization campaign have been reported in the literature to the best of our knowledge
The IPCEI project's overall objective is to enable research and development of innovative technologies and advanced electronics components with focus on strengthening development of production capabilities in Europe. During recent years, mm-wave technologies have shown impressive application potential e.g. for radar application. Recent package technology developments on fan-out wafer-level packaging (WLP) technologies push mm-wave application to mainstream applications. Focus of this special focus session at MIKON 2020 will be to present results from industrial research on mm-wave technologies and their application in the IPCEI. We will present results on two different SiGe semiconductor technologies investigated and developed by GlobalFoundries and Infineon, and we will introduce assembly and package design including antenna integration. We will present results on chip-package-board-system co-design for supporting first time right technology runs. Focus will be to highlight a coherent chip-package-board-system approach. We will discuss potential mm-wave technologies and their technology capabilities. Finally, we introduce potential future applications like radar system for autonomous driving. Representatives of the major European microelectronics industry will give an insight into their R&D work and first results achieved to support development to set-up mm-wave fabrication capabilities of innovative products in Europe.
In December 2018 the European Commission approved a project proposal of four EU member states - France, Germany, Italy and the UK - to start an "Important Project of Common European Interest (IPCEI)" on Microelectronics. It will allow the national governments to spend about €1.8 billion as public support to the project partners for innovative research and development, and investment in first industrial deployment. This presentation will provide a short introduction into the IPCEI project and the five technology fields covered. The project's overall objective is to enable research and development of innovative technologies and advanced electronics components. The importance of R&D in First Industrial Deployment is for the five technologies is highlighted. Of special importance is R&D along the value chain chip-package-board/system. The mm-wave topics of the MIKON Focus Session is an example where the technology fields TF1 Energy efficient chips, TF2 power devices and TF3 sensors collaborate.
Today's SiGe heterojunction bipolar transistors (HBT) in BiCMOS technology environment enable the realization of highly integrated radar sensors for motor vehicles in the range from 76 to 81 GHz at reasonable costs. With fMAX values from 300 to 400 GHz and a fT in the range from 200 to 300 GHz, they form the basis for the wide use of safety-relevant automotive applications such as autonomous emergency brakes, collision avoidance or lane change assist, even in low-cost cars. SiGe HBT BiCMOS technologies therefore led to a strong boost, especially in the development activities for autonomously driving cars. The automotive radar as the first "mass market" for mm-wave technologies and circuits has increased investment in research and development in mm-wave technology considerably. Other, new and emerging mm-wave and THz applications will benefit enormously from this development. The development of SiGe HBT BiCMOS technologies with cut-off frequencies above 500 GHz is about to qualify and start of production. The use of higher operating frequencies and significantly shorter wavelengths enables new and very compact high-performance radar sensors with integrated antennas with high amplification. It offers significantly improved spatial, angular and Doppler (speed) resolution for future autonomous cars, gesture and environment detection in general, personal health monitoring and THz imaging and spectroscopy. The talk gives an overview of the development status of the next-generation 600 GHz SiGe HBT BiCMOS process from Infineon and illustrates the challenges and how they are mastered.
Silicon CMOS technologies have been advancing over decades, such that they start to enter the millimeter wave realm which has been traditionally dominated by BiCMOS and/or III-V technologies. In particular, Globalfoundries 22FDX® technology is a state-of-the-art planar CMOS technology that provides additional unique benefits from fully-depleted SOI for millimeter-wave and RADAR applications. It provides (1) transistors of fT > 350GHz and fMAX > 390GHz; (2) ultralow parasitic capacitances; and (3) novel back-biasing capability fully-integrated into SoC. In this talk, excellent device figure-of-merits will be presented for millimeter wave and RADAR transceivers. Specific features, such as relaxed-pitch, extended device-isolation from substrate, mmW Inductor, etc., are introduced as millimeter-wave enhancements. Finally, circuit demonstrators will be briefly discussed with a summary of 22FDX® platform outlook.
System-in-package (SiP) is a major trend in integration of microelectronic systems to tackle the increasing needs for more functionality into a smaller volume. SiP leads to heterogeneous integration of integrated circuits along with sensors, microelectromechanical components, passive devices, filters and antennas. Another important trend in packaging is the continuing move toward higher frequencies. 5G high-speed wireless communication, mm-wave radar for autonomous driving and high-resolution mm-wave environment sensing and imaging are just a few examples of applications for future markets. In this talk, we present the latest developments in packaging technologies for mm-wave radar and communication systems. We demonstrate the system integration capabilities of the embedded wafer level ball grid array (eWLB) technology. After introduction of low-loss transmission lines and high-quality planar inductors in thin-film redistribution layers (RDL), we present chip-package-board transitions without external matching networks optimized for use in the 60/70/80 GHz bands. We present the concepts of antenna integration in eWLB and show examples of different antenna structures. To demonstrate the system-in-package integration capabilities of eWLB, we show 60 GHz and 77 GHz eWLB transceiver modules with integrated antennas. The use of vertical interconnections and double-sided RDL extend the integration capabilities to the third dimension. We present ways of realizing vertical interconnections in eWLB using through encapsulate vias (TEV) and novel embedded Z lines (EZL) technology. We show examples of vertical interconnections, embedded passives, RF transitions and 3D antennas realized using the TEV and EZL technology. Finally we present the concept of substrate integrated waveguide (SIW) for eWLB. To combine advantages of planar circuits with rectangular waveguides we present a novel, compact and low-loss transition from chip to SIW in eWLB and to standard WR10 rectangular waveguide.
The 1st edition of the IGLUNA - a Habitat in Ice initiative and ESA_Lab demonstrator, run by the Swiss Space Center, was started in 2018 and concluded with a field campaign in June 2019 in Switzerland. A simulated lunar habitat, with a place for surface astronaut activities, was set up on the Klein Matterhorn, in and on the glacier. One of the experiments provided radio communication for the simulated astronauts - a successfully deployed longwave communication system allowed the crossing of the ice barrier between the habitat and the external environment, showing the utility and robustness of this technology in simulated space conditions. The achieved maximal signal range of 2077,06 km, with sufficient signal readability, presented the system as a widely-covering, which, including the very low consumed powers and relatively low total mass, shows it as a promising way of simple, reliable and direct communication for astronauts over a large distances on the Moon. During the conference presentation, many more information and data on the experiment are to be presented.
The paper includes a comparison of performance of two Kalman Filters: extended Kalman filter (EKF) and unscented Kalman filter (UKF) in a hybrid Bluetooth-Low-Energy--ultra-wideband (BLE-UWB) based localization system. In the system the user is localized primarily based on Received Signal Strength (RSS) measurements of BLE signals. UWB part of the system is periodically used to improve localization accuracy by feeding into the algorithm UWB packets time difference of arrival (TDOA). The proposed scheme is experimentally validated using two algorithms: EKF and UKF. The localization accuracy of both algorithms is compared.
This paper gives an overview about the BATS project, which aims to track the behavior of bats by developing an ultra-low power wireless sensor network. It is composed of an ultra-low weight sensor node which is attached to the animal and an extensive ground infrastructure for tracking the animals as well as remote data download of locally stored sensor data from the tags. The system achieves its low power consumption by adaptively enabling certain functions based on the current situation. The mobile node, as key component of the system, contains a variety of sensors, including an electrocardiogram (ECG) to allow precise insights in the animals behavior while maintaining a low weight of around 1g depending on the hardware configuration.
In this paper performance comparison of co-polarized and cross-polarized microstrip Van Atta arrays working in the 60 GHz frequency range is presented. They can be treated as simple chipless RFID tags with frequency response based identification. Tags with three different nominal resonance frequencies of 57, 62 and 67 GHz are designed by scaling optimized base model. Designed 62 GHz co-polarized and cross-polarized arrays with four interconnected pairs of elementary antenna arrays have small dimensions of 20 x 18 mm and 36 x 23 mm, and exhibit RCS levels of -20 and -22 dBsm, respectively. The influence of number of interconnected antennas on the radar cross-section (RCS) of the tag is investigated. Frequency responses of the tags are also examined and compared for both types of tags with 0.80 GHz (co-polarized) and 2.10 GHz (cross-polarized) 3 dB bandwidth of the RCS response at 60 degree interrogation angle.
High power microwaves (HPM) has destructive effect on electronic information system in the short distance, and which is mainly shown as jamming effect in the long distance. Aiming at the evaluation of interference effect of HPM on digital communication system in the long distance, this paper constructs the signal model of HPM jamming communication receiver, analyzes the relationship among bit error rate, jamming distance and duty cycle of HPM pulse. According to the demodulating principle of the communication receiver, the bit error rate (BER) of the communication system on different interference conditions is analyzed by Monte Carlo simulations. The simulation results show that the HPM has significant jamming effect on communication system over a long distance, which verifies the consistency between the theoretical analysis and the simulation results.
This is the second part of the tutorial.
To prevent interference to other radio systems, the measurement and verification of unwanted emission levels, in the spurious domain and the out-of-band domain, are required for the radar systems. Since there is only one commercially available measurement site in the world capable of measuring unwanted emissions in the spurious domain and the out-of-band domain of a marine radar, more measurement sites are necessary. We are going to design and construct a measurement site in Japan. In this paper, we introduce the measurement site and propose how to control multipath propagation. There are three techniques to control multipath waves: narrow antenna beam width, diffuse reflection on the grassy ground, and the use of a reflected wave barrier. A method for estimating the reflection point is also proposed. It uses the interference fringes of the direct wave and reflection waves. The site insertion loss measurements are within +/- 4 dB of the theoretical site insertion loss of free-space.
Multi-beam antenna systems are the basic technology that is used in developed fifth-generation systems. This article is devoted to assessing the impact of a multi-beam antenna system on the interference level in the downlink. These interference are generated by neighboring base station antenna beams. The presented analysis is based on simulation studies in which the multi-elliptic propagation model is used. Transmission characteristics of propagation environments such as power delay profile and antenna beam patterns that define the geometric structure of the model were adopted on the basis of the 3GPP standard. The obtained results show the possibility of using the presented method to assess the separation angle between co-channel beams. It is the basis for minimizing spectral resources in the system.
Antenna arrays are used in many applications, such as space technology or long distance communications. However, there is often an issue of large antennas' sizes for such systems. For example, such a problem is urgent in wideband arrays. This is important because then the distance between antennas in the equidistant arrays cannot be hold. Thus the side diffraction maximums appear. Here we show that conversion to non-equidistant antenna arrays decreases radiation pattern's side lobes for direct radiation and deflection. Based on the methods in the manuscript, we reduced side lobes of our array to -10dB compared to the main lobe. These methods allow calculating non-equidistant antenna arrays with high accuracy using information about antenna's characteristics. Thus, the side radiation is decreased and the antenna array efficiency is improved.
Contemporary UWB positioning systems are able to provide excellent positioning accuracy. However, if the system is deployed in an environment where the propagation channel is demanding the positioning errors are significantly bigger. The paper contains a description of a method for correction of time difference of arrival measurement results. The applied offset corresponding to current tag location. Fingerprinting technique is used for correction data preparation and selection. The method efficiency was verified with measurements performed with UWB positioning system. The paper contains description of the proposed method. Results of experiments are included and discussed in the paper.
In this paper, the concept of direction of arrival (DoA) estimation using electronically steerable parasitic array radiator (ESPAR) antenna designed to operate in IEEE 802.11p vehicular communication standard has been investigated with respect to different possible elevation angles of a radio frequency (RF) signal impinging the antenna. To this end, two different possible sets of the 3D antenna radiation patterns have been used together with power-pattern cross-correlation (PPCC) algorithm and its extension that covers multiple calibration planes (PPCCMCP). Numerical simulations of the PPCC and PPCC-MCP angle estimation procedures at 5.89 GHz have been performed to verify the overall DoA estimation accuracies in the horizontal plane for different, and unknown at the moment of estimation, elevation angles.
In this paper, a 1x2 dual-band microstrip antenna array configuration in FOWLP technology for 5G applications operating in the 28 GHz and 38 GHz frequency bands is proposed. For the first time the antenna array is designed, simulated and fabricated on 200 µm mold substrate material for a compact 1 cmx1 cm Antenna-in-Package module. Results show a good correlation between simulation and measurement. A measured impedance bandwidth of 400 MHz is achieved at both 28 GHz and 38 GHz frequency bands, whereas the maximum antenna gain is approximately 6 dBi.
The European Spallation Source (ESS) is a next-generation neutron source, under construction in Lund, Sweden. An important requirement for ESS is to assure a precise phase synchronization of LLRF and Beam Diagnostics systems. They are operating at frequencies of 352.21 MHz and 704.42 MHz. The phase stability along the machine is provided by the phase synchronization system. The main part of the system is a Phase Reference Line (PRL). It is an entirely passive system based on a single coaxial rigid line located in the tunnel, which distributes both reference frequencies. A source of the reference signals is a Master Oscillator (MO) located in the Klystron Gallery. High power amplifiers used at each frequency provide a power level of about +50 dBm. The output signals are combined in a custom made diplexer. The two-tone signal is distributed to the tunnel by a single 7/8" coaxial cable. Ambient temperature variations and humidity changes in the tunnel, STUB, and Klystron Gallery cause the phase drifts in the phase distribution system. An active drift compensation system was necessary to reduce those phase drifts. This paper shows the concept and block diagram of the RF connection from MO to PRL.
FLASH, a soft X-ray free-electron laser facility, is currently subject to several ongoing and planned upgrade activities. The underlying control and synchronization systems also have to keep up with the changing requirements. Therefore, in order to provide improved performance and better maintenance experience, a new master oscillator system is proposed. Most significant improvement can be seen in the jitter performance, bringing sub-10 fs rms integrated jitter which is an order of magnitude better than the present system. The first parts of the system are expected to be operational in mid-2020, while the final system installation and commissioning are scheduled for the beginning of the year 2021.
A 6.27 GHz energy-efficient noise filtering class-F oscillator is designed in a 22 nm SOI CMOS process. A transformer-based resonator is adopted boosting the third harmonic of the fundamental wave and expanding phase insensitivity region in one oscillation period. The noise filter comprised of an inductor and a capacitor is used to reduce both the Q factor degradation of the resonator and the 1/f noise upconversion at the same time. Post-layout simulation results considering accurate 3D models for all relevant components proof an excellent phase noise of -127.5 dBc/Hz at 1 MHz offset drawing only 5.0 mW power consumption from a 0.8 V supply resulting in a figure of merit(FoM) of 196.4 dB.
We present a concept of a novel redundancy solution for the master oscillator of the European-XFEL facility. The solution implements automated switching between identical copies of the reference signal generation chains. The main difference from prior solutions is the ability to maintain a continuous reference signal also in the event of switching, e.g. caused by a failure in the system.
The IPCEI project's overall objective is to enable research and development of innovative technologies and advanced electronics components with focus on strengthening development of production capabilities in Europe. During recent years, mm-wave technologies have shown impressive application potential e.g. for radar application. Recent package technology developments on fan-out wafer-level packaging (WLP) technologies push mm-wave application to mainstream applications. Focus of this special focus session at MIKON 2020 will be to present results from industrial research on mm-wave technologies and their application in the IPCEI. We will present results on two different SiGe semiconductor technologies investigated and developed by GlobalFoundries and Infineon, and we will introduce assembly and package design including antenna integration. We will present results on chip-package-board-system co-design for supporting first time right technology runs. Focus will be to highlight a coherent chip-package-board-system approach. We will discuss potential mm-wave technologies and their technology capabilities. Finally, we introduce potential future applications like radar system for autonomous driving. Representatives of the major European microelectronics industry will give an insight into their R&D work and first results achieved to support development to set-up mm-wave fabrication capabilities of innovative products in Europe.
Heterogeneous integration leads to significant increase in design complexity. This complexity can be handled properly only by an enhanced design environment and extensive use of electronic design automation (EDA). It turns out that such a design system needs to be based on multi-dimensional modularization: modularization in configuration (like assembly design kits, so-called ADKs), modularization in data exchange and data storage (standardized file formats and data management), and modularization in design environments (even across company boundaries). We have developed a versatile, generic design flow environment, which enables the configuration of several ADKs in addition to a process development kit (PDK) for a complete chip-package-board design project. The content of an ADK has been aligned with the underlying set of EDA tools in the corresponding design flow. It needs to enable and support various steps in chip-package-board co-design: • Connectivity (schematic) entry • Concurrent layout design both in fully automated digital place-and-route as well as in full-custom manual style • Assembly design rule checks (DRC) • Overall connectivity checks: layout-versus-schematic (LVS) even across chip, package, and board domain • 3D model generation for subsequent package parasitic extraction and electro-magnetic field simulation We present a modular full-custom chip-package-board co-design environment based on a versatile backbone idea and a powerful concurrent layout environment, which has been applied successfully to various system-in-package (SiP) designs. We show design methodology challenges and the application of our co-design flow to RF and mmWave designs in fan-out WLP (FOWLP) or laminate BGA and LGA.
Consolidation of 4G LTE and 5G networks and emergence of 6G is calling for higher rates wireline and wireless connectivity solutions. This presentation will give an overview of the main high-rate links where mmW capable technologies are required. A review of associated addressable markets will be also discussed with some consequences in terms of Silicon process options. More detailed mmW technology description will be displayed concerning STMicroelectronics proprietary SIGe BiCMOS and CMOS on SOI process flavors giving an industrial answer to mmW challenges. Access to STMicroelectronics mmW capable technologies through Multi-Project Wafer production schemes within IPCEI on Microelectronics or European collaborative projects will be explained. Examples of circuit performances will be presented to illustrate the added-value in terms of speed, noise, power efficiency…Some advanced roadmap information will be disclosed about forthcoming process from STMicroelectronics as well as some insights on collaborative R&D projects in the scope of mmW to contribute in building European vision on mmW industrial future.
Millimeter-wave radar provides robust high-resolution distance, velocity, and angle information, as well as small-movement characterization. With the advent of low-cost semiconductor and packaging technologies that allow mass-producing millimeter-wave components, the widespread use of millimeter-wave sensors has started to become reality. Since the first introduction in the automotive area, radar has become a key sensing modality for driver assistance and automated driving. Here, a new generation of sensors and algorithms moves radar sensing from simple detection to classification and mapping. Additionally, new applications in robotics and consumer devices are starting to be realized. Small size, invisible integration, low-cost, and privacy are some of the advantages radars provide here. However, key for widespread adoption is a systems-approach that significantly reduces the application effort by using a single-piece digital-and-analog packaged component. Some obstacles to widespread adoption remain. Technical challenges include how to interpret and apply the sensor information to the given use-case, and low-power operation to make battery-operated devices feasible. On the non-technical side, world-wide harmonized frequency regulation remains a challenge.
Highly-Integrated Millimeter-Wave Frontends for Complex Radar Sensor Systems
The dielectric properties of materials applied in advanced packaging technologies such as Fan-out Wafer Level Packaging (FoWLP) must be precisely known at mm-Wave frequencies for optimized package design. In this paper, the applicability of fork-coupled resonators for the electromagnetic characterization of an epoxy molding compound (EMC) for 5G applications is investigated by means of full-wave simulations. The analysis is experimentally verified by means of measurements of fabricated test structures on EMC (Nagase R4601-X65) material for 5G applications in frequency bands of 26.5-29.5 GHz and 37-40 GHz.
It is shown in this paper that a Fabry-Perot open resonator is applicable to the measurement of in-plane anisotropy of dielectric constant and loss tangent of laminate materials in microwave and mm-wave range. This is doable provided that linearly polarized TEM0,0,q Gaussian modes are exploited. Measurements are undertaken in an automated setup operating in the 20-50 GHz range and anisotropic thin PET foil is characterized.
The work proposes and validates a methodology for efficient imaging of material samples with a recently developed portable 2D scanner incorporating a 10 GHz split-post dielectric resonator and driven by a low-form-factor vector or scalar network analyser. First, experimental studies are conducted to evaluate the influence of the network analyser operating parameters on the accuracy and stability of complex permittivity extraction. The settings of 1 kHz intermediate frequency bandwidth and 200 frequency points within the measured band are selected, as a cost-to-accuracy compromise. Then, a post-processing procedure based on Lorentzian curve fitting is applied to the raw response, to further enhance the measurement accuracy and stability. The methodology is applied to three materials, and a 2D scan of a laminate sample demonstrates the achieved efficiency.
Homogeneous and inhomogeneous electromagnetic metasurfaces are designed to enhance the gain of patch antennas operating at 10 GHz. The metasurface consists of metallic split ring resonators, which can be fabricated with conventional printed circuit board technology on the top of a low loss substrate material. The metasurfaces are mounted above the patch antennas. It is shown by simulations and measurements that the gain of the metamaterial antennas at the operating frequency of 10 GHz have a threefold gain increase compared to the standalone patch.
This paper presents a 28GHz broadband low noise amplifier (LNA) with a fractional bandwidth > 32 % for 5G wireless communication systems. The LNA provides a very low noise figure, a high linearity and a compact size. These properties are essential in a 5G MIMO receiver front-end. The LNA is designed in a 130 nm SiGe BiCMOS technology and provides 24 dB gain at 28 GHz with a 3 dB-bandwidth from 21.4 to 30.6 GHz. The simulated noise figure at 28GHz yields 2.18 dB. An input-referred 1 dB-compression point of -13.0 dBm is reached with a DC-power consumption of 25.1 mW.
The paper investigates experimentally the effect of harmonic terminations on AlGaN/GaN power amplifiers (PA) performance at K-/Ka-band. Two technologies are compared, a 0.25um and 0.1um process. In both cases, a harmonic termination increases the achievable output power by about 10 % at the expense of bandwidth, whereas the efficiency is improved only in the first one.
This paper shows design and development of a highly integrated solid state power amplifier (SSPA) for new-space earth observation satellites. The SSPA operates in frequency range of 8.025 - 8.4 GHz with 20 Watt output power at input power range of -20 dBm to 0 dBm and power added efficiency (PAE) reaching up to 35 %. Although the main application of presented SSPA is earth observation (EO) it can be used in ground segment, e.g. for radar application as well.
This work presents a self-biased 2-stacked power amplifier cell that shows, between 33.5 GHz and 39.5 GHz (16% fractional bandwidth), an output power in excess of 33 dBm and gain and PAE above 6 dB and 27%, respectively. The cell has been developed on a commercial 100nm GaN-on-Si process, applying space derating rules at center frequency, where the output power is almost 33.8 dBm, the associated gain is higher than 7 dB and PAE is above 35%.
This paper presents two calibration procedures for ultra-wideband SDR Zero-IF receiver operating in 1 GHz to 6 GHz frequency range. The IQ-imbalance compensation procedure trained with an additional testing monochromatic signal and based on complex FIR filter allows Image Rejection Ratio (IRR) better than -65 dBFS over 600 MHz bandwidth. For DC-offset minimization a hybrid method based on AC coupling with very low cut-off frequency and DAC-controlled hardware balancer of ADC inputs was developed. The level of the DC component in the output spectrum after calibration is close to -70 dBFS. Stability of both compensation methods over time has been examined.
In this paper, an incremental modeling technique is proposed as an efficient substitute for the costly approximation methods used in behavioral modeling of active microwave devices. In this technique, cheap interpolation models are being extracted on a subset of training dataset. The rest of the dataset guides the algorithm which samples to include in the interpolation. The model is built by subsequently adding the samples that minimize the information loss given by Akaike information criterion. This criterion allows to choose a good compromise between the model accuracy and complexity. The results of the modeling of the complex wave quantities of GaN HEMT show that incremental modeling yields comparable and sometimes lower errors to the models interpolating with even order-of-magnitude more samples. The results also show that the incremental modeling greatly reduces overfitting.
The use of the calibration tower to test a monopulse tracking system is expensive and requires the antenna downtime. Alternative ways to test in-lab the tracking system are highly-desirable. This work proposes a simple yet effective structure achieving this objective through the controlled excitation of high-order modes in a circular waveguide that mimic those generated by the signal received from the calibration tower. The theoretical fundamentals are discussed and the design of the waveguide mode exciter at K band is reported, along with results showing its validation.
Analog-Multiplexers (AMUXs) are attractive architectures to increase electro-optical transmitters' analog bandwidth through the time interleaving of several high-speed digital-to-analog converters' outputs, to enable the transmission of high order electrical modulation formats (PAM-4, PAM-8) for ultra high capacity (>1Tb/s/channel) optical communications. In this paper, we present the design, fabrication and measurement of AMUX circuit realized in the III-V Lab in-house InP DHBT technology. The design challenges and necessary tradeoffs are discussed. Measurements of PAM-4 AMUX output signals up to 100 GBd with an over 1-V differential output swing are presented.
In the paper, microwave amplitude and phase noise mutual conversion is studied for optoelectronic oscillator (OEO) with all-optical gain. It is shown that microwave amplitude and phase noise mutual conversion in the OEO loop is possible due to its non-linear time-variant dynamics, especially in the state near the oscillation threshold. The correlation between amplitude and phase noise effects the OEO output noise power spectrum density. It is shown experimentally that decreasing of the amplitude noise injected in the OEO loop allows to decrease the phase noise of the output signal. Methods for reducing the amplitude and phase noise mutual conversion and consequential phase noise performance increasing are proposed.
Rapid development of terahertz technologies causes constant search for new possibilities of making optical elements, needed for proper beam shaping. Large optical elements are often used in THz setups to collect as much power as possible. Unfortunately, traditional refractive optical lenses significantly absorb already weak signal. This is the reason for searching for new solutions in the form of diffractive optical elements (DOEs). For higher terahertz frequencies however, it is challenging to find an appropriate material as well as uncomplicated manufacturing methods. In this article, we present a higher-order kinoform (HOK) made of paraffin, cast from 3D-printed mold, efficiently working for 0.6 THz.
Every new optical element require proper characterization. The same situation is with diffractive elements working in terahertz range. In this paper we present the procedures applied for measurements of an off-axis diffractive lenses. Problems and solutions for noncollinear experimental setup configuration are discussed. Results acquired by using three semiconductor detectors with different apertures are compared.
This paper presents the design of a D-band frequency quadrupler (FQ) based on two cascaded frequency doublers. Each doubler relies on the bootstrapped Gilbert cell (GC) mixers. The FQ is developed with a standard 130-nm SiGe BiCMOS process. It consists of fully integrated input and output baluns, frequency doublers, and matching networks. The design of the FQ was optimized via single-ended matching networks to reduce the chip area and increase bandwidth. The results based on the EM-simulation of FQ with the assistance of the hicum model for the transistor, demonstrate a peak conversion gain and output power of 25 dB and 5 dBm, respectively at 130 GHz. The FQ shows a 3-dB bandwidth higher than 84 GHz with an nth harmonic rejection of at least 16 dBc. The FQ can be exploited in various systems design for different D-band applications. The future work includes measurement of the FQ.
A comparison of techniques for software calibration of lumped ports is presented in this paper. Three calibration techniques are investigated: double delay method, short-open calibration, and analytic evaluation of port parasitic inductance. All methods were applied to the same microstrip device and the efficiency of each calibration technique is discussed in the results section.
We investigate the concept of multitone X-parameters for characterizing the behavior of an off-the-shelf power amplifier under wideband excitation similar to real-life telecommunication signals. To achieve this, we created a set of random phase multitone excitations and identified large- and small-signal terms for each wideband signal. For simplification, we ignored terms describing mixing and harmonic-related products. We show how the terms identified are affected by input signal conditions by presenting and discussing results for two exemplary multitone realizations. For this investigation, we kept the power amplifier's load conditions constant.
This paper presents a wireless planar microwave sensor operating at industrial scientific and medical (ISM) frequency for the detection of dielectric materials. The microwave sensor consists of a reader (ground defected microstrip coupled line) and a passive tag where a complementary split-ring resonator (CSRR) made on the commercially available copper-foil. The CSRR is a peel-off type tag that is excited using the near field of microstrip coupled transmission line. The near field coupling, the low-cost passive tag design, and the high sensitivity (~250 MHz change per unit change in dielectric constant) make the proposed sensor wireless, cost-effective, and reliable.
We describe a new system for broadband characterization of mid-infrared (MIR) photodetectors, manufactured by the VIGO System and encapsulated in TO-8 can. The system comprises a high repetition rate pulsed laser source, stimulating a detector in a special test fixture that is connected to ports of a vector network analyzer (VNA) with a pair of cables. After calibrating the VNA at the cable ends using the thru-reflect match (TRM) method supplemented with power and phase calibration, it operates in mode of nonlinear VNA, i.e. it is capable of measuring magnitude and phase spectra of harmonic signals both corrected for effects of systematic errors. In order to recover the differential signal at the detector reference plane on the can header, we utilize the transfer matrix of the test fixture, which counts 16 nonzero entries due to signal crosstalk in the fixture. This matrix is determined with another calibration procedure, based on measuring special built-in-house standards, mounted inside TO-8 housing. With the matrix determined, we transfer the measured spectra to the TO-8 reference plane and then convert them with IFFT to the time-domain. This approach enables recovering sub-nanosecond differential pulses of amplitudes below 1 mV and speed up performance evaluation of MIR detectors tested.
The analysis of the possibilities for the fully digital microwave frequency discriminator (MFD) realization has been presented in the paper. In classic hardware solutions MFD consists microwave phase discriminator and microwave detectors, realized as microwave circuit. Authors propose a solution completely deprived of the analog microwave circuit, based on the fast A/C converter. Mathematical operations carried out in the microwave circuit are digitally executed, on digital signal samples. The receiver was implemented as the 3-channel MFD, this one gives unambiguous determination of the instantaneous frequency value and high accuracy in the 700 - 3000 MHz band. For the physical implementation fast digitizer with 12,5 GS/s speed was used and the overall digital processing in the programming LabVIEW environment has been realized. Proposed solution corresponds to the parameters and functionality of the MFD systems in the classic version. Laboratory tests with real RF signals have been made. The measurement accuracy not worse than 10 MHz were obtained, with the most measurements being no worse than 3 MHz.
The paper summarizes experience with the development of high-frequency electronic components which are manufactured on a three-dimensional knitted material instead of a conventional microwave substrate. Attention is turned to specific aspects of the design, manufacturing and integration of components to applications. Technological problems, which have not been solved yet, are discussed.
The paper summarizes the experience with the development, production and optimization of 3D fabrics, specifically 3D weft knitted fabrics, planned for the integration of electronic components. Attention is focused on the presentation of 3D fabrics general properties which are given by their structure, used materials and finishing. The technological possibilities of preparation of this type of fabrics are summarized and their limits are described in detail and possible application areas are outlined. The possibilities of surface treatment from coating, lamination to printing or embossing are presented in order to optimize the fabric surface for a given application.
The paper deals with the relative permittivity measurement of the selected types of 3D-knitted fabrics by the two-line method combined with the matrix-pencil method and by the transmission/reflection method. The measured relative permittivity of the fabrics is in the range from 1.17 to 1.23. Further, the fabrics exhibit slight anisotropic behavior. The obtained results can be used for the design of the microwave devices where the 3D knitted fabrics play the role of the substrate.
The paper summarizes experience with electromagnetic interference (EMI) noise background measurements on the board of aircraft EVEKTOR EV-55 in the development phase. Measurements were aimed to select optimum frequency bands for the operation of on-board textile-integrated electronics. The EMI background was measured in four places situated along the center of the aircraft body. Measurement scenarios comprised several aircraft operation conditions like the running engine, power only on batteries, transmission on the radio etc. The appropriate ISM communication channel at 5.8 GHz was selected due to the lower noise interference and acceptable dimensions of textile-integrated microwave components.
In the paper, frequency limitations of textile integrated antennas and filters based on textile integrated waveguides are discussed. The antennas and filters are manufactured from a three-dimensional knitted material. Conductive parts are manufactured from silver-coated conductive threads and by a screen-printing technology. Textile antennas and filters presented in an open literature are reviewed and compared. The technology, manufacturing process and limitations are analyzed and discussed.
The purpose of this work was to create a wireless Internet-of-Things (IoT) communication module for a device for measuring soil parameters in a field environment. The module uses the Low Power Wide Area Network (LPWAN) technology to exchange data with an external database. This paper contains information about design assumptions, research on the existing long-range communication technology solutions and description of the design process.
This paper presents a method for determining a six-port reflectometer's response to a matched load with the use of partially known calibration loads. It utilizes nine calibration loads which can be of unknown magnitude and phase, however, three of them must exhibit magnitudes possibly close to each other with a reasonable phase separation. The algorithm was tested with the use of an exemplary broadband six-port reflectometer operating over the frequency range from 2.5 GHz to 3.5 GHz. The power values obtained using the proposed method are very close to those directly measured by the six-port reflectometer with a broadband matched load from precision calibration kit connected as DUT.
In this paper authors presents very important problem of estimation capacitance structures used in MEMS sensors. The importance comes from fact that during operation, inertial sensors which are build of solid materials deform because of external forces acting on them. Therefore typical capacitor consists of some electrodes changes its value because electrode changes its orientation. Here authors use analytical and FEM results to compare capacitance results and impact on accuracy of measurement.
In the paper authors take into considerations results of analysis both MEMS accelerometers and gyroscopes under performance that can be changed by some geometry details modifications. Authors considers different types of shapes of springs to show, how they influence on total device operations.
The instantaneous frequency measurement (IFM) devices are very useful for very fast measurement of current frequency value of microwave signals even if their duration is extremely short. A fast measurement of temporary value of frequency is based on evaluation of a phase difference of signals propagating through the microwave transmission lines having unequal but known lengths. This phase difference is provided by so-called proportional phase shift forming network (PPhSFN), and the phase difference measurement is performed by the microwave phase discriminator (MPhD). The main segment of MPhD is a microwave six-port made of several microwave splitters and combiners. The paper presents integrated version of microwave correlator containing PPhFS and six-port on a single printed circuit board (PCB). The developed device was designed to work over WiFi frequency range. The frequency bandwidth of the made correlator reaches nearly one octave.
The paper presents the attempt of finding optimal solutions regarding the emission type, basic emission parameters and channel capacity for the trans-ice longwave communication channel, as deployed in June 2019 during the first edition of the IGLUNA programme - a simulated lunar habitat in the Klein Matterhorn glacier in Switzerland. The experimental system is compared to lowland high-power longwave systems, the optimal emission type for different conditions (modulation index, demanded presence of carrier) is presented and the maximum possible channel capacity in relation to the achieved signal readability is calculated.
High power electromagnetic pulse weapon (EMP) is a new kind of weapon which can directly transmit high power microwave to damage the target electronic equipment. This paper introduces the damage mechanism of high power microwave, describes the working principle of the marine navigation radar and the front-end structure of receiver. The damage ability of high power microwave to marine navigation radar receiver is calculated and analyzed, at the same time, the damage range of high power microwave to marine navigation radar is given under the different states of power center and power edge.
3D printing offers a very innovative opportunity for creating cheap or special rf-components like waveguides, couplers or antennas. However, these components require electrical conductive materials to be built of. Therefore, selective laser melting of metal powder is also an attractive production technology. In this paper, horn antennas and a directional coupler at 24 GHz are shown and their production technologies are compared. By presenting a K-band branchline coupler it is shown that selective laser melting has some advantages over 3D printing.
The proposed radar system is characterized by cheap equipment (omnidirectional microphones, a computer for signal processing, and peripherals) and by the special algorithm of signal processing, which has been developed and tested during full-scale experiments with real targets: aircrafts and UAVs. A key feature of the developed algorithm is a fast method of estimation of wideband ambiguity function. In addition, the algorithm provides visualization of the target location process using the projection of the ambiguity function onto a coordinate plane. The developed radar system is proposed to use for aircraft noise management in the vicinity of an airport and for localization of small-sized flying vehicles. The results of the experiments are presented in the paper
the Weightless(-P) is a narrowband communication system designed for the Internet of Things, along with some other counterparts such as Lora and SigFox. As a system dedicated specifically for long-range operations, it possesses a considerable processing gain for the energetic link budget improvement and a remarkable immunity to multipath and interference. The paper describes outcomes of measurement campaign during which the Weightless(-P) performance was tested against variable interference, generated in an anechoic chamber. Results allow to quantitatively appraise the system behavior under these harsh conditions with respect to the modulation and the resultant bandwidth. The outcomes allowed to propose recommendations regarding the use of particular system settings to optimally fit environmental conditions. Finally, the paper provides an analysis in which CNIR is converted to the Interference Margin and its value is checked against an intentional jammer approaching the base station to verify how different Weightless operational modes respond to electromagnetic jamming.
This paper deals with a model-order reduction method, applied to speed-up the simulations of MIMO antenna arrays, performed by means of finite element method. The obtained results of the numerical tests show that the described technique is reliable and considerably increases the efficiency of the standard finite element method.
Radar technology in the mm-wave frequency band is a promising approach for the detection of birds and bats at wind turbine installations in order to reduce fatalities either by direct collision of the animals with the rotor blades or through barotrauma. In this paper we present an FMCW radar system with 1 Tx and 9 Rx operating in the Ka-band from 33.4 GHz to 36.0 GHz. The radar system is installed at the tower of a 2MW wind energy plant about 95m above ground. The data acquisition is described in this paper including the real-time processing pipeline, followed by exemplary bird detections. Also the detection of drones, serving here as an artificial flying object with a defined flight path, will be presented and discussed. Validation is performed by concurrent camera recordings.
The specially calculated reflecting surfaces with Stealth invisible quality designed for to avoid vertical ones for ra-dar beam and to reflect beam "to the milk". Stealth coatings with the full absorption of the micro-wave radar radiation on his surfaces are blackbody and reasonable to consider it as the matched loading with the corresponding physical outside temperature. A lot of news and minding has place about the Stealth application especially in the contest of an airplanes. Possi-bility to avoid the disclosing of an airplane on the big dis-tances is main advantage of this Stealth "addition" against of the radars. But in much cases for the microwave radi-ometers this Stealth coating can be good for the real deter-mination by the passive devices because their job based on the measuring the radio-brightness contrast between Stealth objects and the background of the environment/s (sky is cold, Earth is warm). The aim of this short report - to present some under-standing about to use radiometer about Stealth objects
In this paper, influence of dielectric overlay permittivity on miniaturized ESPAR antenna parameters is presented. ESPAR antenna is a low-cost and energy-efficient way to implement beam steering capability to a node and improve network performance. The antenna size reduction is obtained by embedding its active and passive elements in ABS based materials of relative permittivity equal to 4, 5.5 and 7.5 in order to achieve network node compact size. Simulation results of three optimized for particular dielectric constant designs are presented and tradeoff between dimensions reduction and performance is discussed. Selected materials and antenna design are dedicated to be fabricated in 3D print technology, so can be easily prototyped.
Microwave propagation in the atmosphere is affected by air temperature, humidity, attitude, and other factors, there are many related researches on the above influencing factors, but relatively few researches are attached on the microwave propagation characteristics under the condition of sea salt mist. It is of great significance to clarify the law of microwave propagation attenuation under the condition of salt mist for the microwave applications such as maritime communication and radar detection. Firstly, the parameters of the salt mist environment are analyzed and modeled in this paper, and it is driven that the relationship between the concentration of the salt mist and the dielectric constant of the atmosphere. Then, based on the FDTD numerical analysis, the microwave propagation law under different concentration of the salt mist is calculated and compared with the theoretical analysis results.
This paper describes an experimental setup that was built to imitate the performance of the new microwave personnel screening system, in which synthetic aperture is formed due to relative motion of the subject in the vicinity of a sparse antenna array. The RGB-D sensor captures a color image and a depth map of a still scene with a mannequin, while the compact network analyzer, which is moved by a two-dimensional scanner, acquires the samples of the radar signal reflected from the same scene. The mannequin is moved by the third linear drive module to another position, creating the next still scene to be scanned and captured similarly during a single experiment. The collected data is stored for the following joint processing. Preliminary radar images of concealed objects on mannequin are obtained and demonstrated. The use cases of the experimental setup are described toward designing a sparse electronically switched antenna array: finding the required number of the channels, choosing proper frequency band and bandwidth, antenna type, and others.
The paper presents an algorithm for positioning of a handheld ground-penetrating radar antenna. The algorithm has been elaborated for processing range measurements in a currently developed positioning system based on ultrawideband radio modules. Such a system is planned to be used as a support for a handheld ground-penetrating radar as continuous and accurate positioning of its antenna can facilitate creation of high-quality subsurface images. The paper contains a short description of the developed system and focuses on its Kalman filter used for positioning. Here, we consider using a novel dynamics model, based on a pendulum motion model, which provides a more adequate description of the antenna's dynamics than abstract position-velocity or position-velocity-acceleration models, commonly used in navigation systems. Chosen simulation results which support this claim are presented.
The paper presents an implementation of analog front-end designed for use in an X-band Frequency Modulated Continuous Wave (FMCW) radar system. Fine range resolution is achieved because of using more than 1 GHz of bandwidth, which is achieved through application of frequency multipliers. The system has been tested in laboratory as well as in a real environment using a USRP (Universal Software Radio Peripheral) device for both, waveform generation and beat signal digitization.
Background subtraction is usual step in impulse radar applications. It is used to not only remove clutter - reflections of all the stationary, mostly irrelevant objects, but also crosstalk. Various techniques are used for clutter/crosstalk removal. These are briefly over-viewed. Focus of this paper, however, is on proposed method of adaptive background subtraction, which is statistical real time method based on developments of entirely different field (Computer Vision)
This paper explores the possibility of using a synthetic aperture radar to detect surface defects of rails and measure parameters of rail junctions. Experimental data were obtained with a setup consisting of a two-coordinate electromechanical scanner and a radar emitting continuous stepped-frequency signal in the range of 22.2 - 26.2 GHz. As an object of study, fragments of narrow-gauge rails were used, in which surface defects of various sizes and depths were created. A phase method for radar signal processing based on the backward propagation of its wavefront was developed, with which radar images of rails with defects were obtained. Experimental studies have shown that the developed rail surface imaging method allows detecting the presence and measuring characteristics of cracks on the tread, cleavages of the railhead, the width of the joint gap and the magnitude of the vertical step at the rails joint. High accuracy and sensitivity of the radar method, confirmed with the contact measurements matching, allow using it for fast noncontact diagnostics of the rails condition.
For polarimetric synthetic aperture radar (PolSAR) images, building extraction has been a challenging topic for long time in applications of land-use and land-cover analysis. Due to similar structures of buildings and such vegetation as forest, they often exhibit similar PolSAR scattering characteristics that are often difficult to distinguishing. Recently, deep Convolutional Neural Network (CNN) has been widely investigated for image processing with many promising results. This paper proposes a method that combines polarimetric features with the CNN network to realize the comprehensive utilization of polarimetric and contextual information of PolSAR data for the extraction of building areas in PolSAR images. Comparison experiments on both ESAR and EMISAR L-band PolSAR datasets show that the proposed method can generate better results for building extraction.
Recently, Interest on circular SAR (CSAR) has been increased in researchers. The sub-aperture division and trajectory reconstruction of ground moving target are important parts of the CSAR research. Firstly, the CSAR sub-aperture is fitted by a second-order curve, which achieves better focusing quality than the traditional fitting method. Next, parameter estimation accuracy is improved of each CSAR sub-aperture. Finally, the trajectory of ground moving target is reconstructed. Simulated data are used to prove the effectiveness and correctness of the proposed method.
This paper introduce an approach for detecting bridges when the difference in radar echo energy is not obvious. It consists of two steps: extracting targets with high anisotropy and detecting bridge. Firstly, by image segmentation based on the feature of multi-aperture polarimetric entropy, we get targets with high certainty. And then we utilize edge detection to extract straight line segmentations. Finally, the parallel straight line segmentations which meet the bridges' geometric properties are selected as bridges. The proposed approach has been test with polarimetric CSAR data, and the experimental results show that our method can detect bridges effectively.
A novel global range alignment technique for inverse synthetic aperture radar (ISAR) imaging is presented in this paper. Instead of requiring the parametric model for the relative offset amongst the range profiles, the alignment is investigated from the viewpoint of optimization, where the minimization of the entropy of the sum range profile (SRP) is employed as the optimization criterion. The precise range alignment within a range cell can be achieved by implementing the proposed algorithm. With respect to the existing global method, the proposed one does not require any interpolation operation and multidimensional search operation. Experimental results based on real measured data of maritime non-cooperative target validate the effectiveness and the efficiency of the proposed algorithm.
In this paper, a general iterative thresholding algorithm (ITA) for solving Lq-norm regularization problem is proposed to achieve the synthetic aperture radar (SAR) image feature enhancement. Compared with the reconstructed images by matched filtering (MF) based method, the proposed method recovered images have lower sidelobes, reduced noise and clutter, which improves the image quality effectively. Experiments basedon Gaofen-3 (GF-3) SAR complex image data are used to validate the proposed method.
A real-time imaging right side-looking synthetic aperture radar (SAR) motion error model is established in this paper, and a center beam motion compensation algorithm based on inertial navigation and phase gradient autofocus (PGA) motion error estimation is adopted. The algorithm compensates the echo envelope and phase separately, and uses the inertial navigation data to straighten the echo envelope with motion error, and then uses the phase gradient autofocus algorithm to estimate and compensate the phase error of the echo. In view of the characteristics of real-time imaging, such as short time, large amount of computation and limited computing resources, the algorithm cancels the steps of range migration correction, projects the motion error vector on the slant plane, and completes envelope correction and phase error estimation. The method has a small amount of calculation and can meet the resolution requirement. The simulation results show that it can obtain high quality SAR images.
Surveillance radars form the first line of defense in border areas. But due to highly uneven terrains, there are pockets of vulnerability for the enemy to move undetected till they are in the blind range of the radar. This class of targets are termed the 'pop up' targets. They pose a serious threat as they can inflict severe damage to life and property. Blind ranges occur by way of design in pulsed radars. To minimize the blind range problem, multistatic radar configuration or dual pulse trans- mission methods were proposed. Multistatic radar configuration is highly hardware intensive and dual pulse transmission could only reduce the blind range, not eliminate it. In this work we propose, elimination of blind range using deep learning based video tracking for mono static surveillance radars. Since radars operate in deploy and forget mode, visual system must also operate in a similar way for added advantage. Deep Learning paved way for automatic target detection and classification. However, a deep learning architecture is inherently not capable of tracking because of frame to frame independence in processing. To overcome this limitation, we use prior information from past detections to establish frame to frame correlation and predict future positions of target using a method inspired from CFAR in a parallel channel for target tracking.
Space-Time Adaptive Processing (STAP) enables detection of a moving object against the background of strong interference by radar. The fundamental principles of the STAP technique for radar signal processing in particular, detecting slow moving objects against interference. are presented in this paper. The parameter (improvement factor), determining the performance of any linear processor was analysed. A disturbance model has been proposed, for which the dependence determining the performance of any STAP processor has been derived. The results of simulation of the optimal processor performance against the suboptimal processor for three different values of noise to interference ratios in reference channels were presented in the paper.
This paper concerns the problem of maximum likelihood (ML) estimation in the case of impulsive observations modeled by heavy-tailed α-stable distributions. To describe analytically the cost function in ML estimation criterion the Fox function representation of α-stable distributions is used.
The paper presents the results of experimental studies on evaluation of employing digital predistortion based on simple feedforward neural network for linearization of microwave power amplifiers. The influence of the number of neurons in the hidden layer, the number of delayed input samples at the input of neural network, as well as the number of samples taken for learning a neural network were studied and discussed in the paper. The main goal of this work was to establish the minimal configuration of the neural network which can be used for linearization of power amplifiers excited by wideband and high PAPR signals, e.g. LTE. The results obtained for neural networks were compared with the results obtained for the conventional predistortion method based on memory polynomial.
We report anomalous behavior of the response in GaN/AlGaN fin-shaped field effect transistors at sub-THz frequency range. For transistors with the gate length much bigger than the width of the channel an unusual growth of the absolute value of the response signal was observed with applying positive gate voltage.
In this paper, we show experimental evidence of the applicability of a field-effect transistor-based THz detector (TeraFET) for the simultaneous hyperspectral raster scanning imaging. For this work, we have used a dual frequency comb setup extended to THz frequencies, as well as a TeraFET detector adopted for a higher frequency readout circuit. Such a spectroscopic imaging system can acquire simultaneously many frequency lines with an outstanding frequency accuracy and adjustable frequency resolution even at very low THz source power. The dual frequency comb THz system is also capable of narrow linewidth, which makes spectroscopy measurements with high resolution more feasible. The TeraFET detector has optical NEP below 19 pW/Hz^0.5 at 296 GHz. Additionally, the detector was supplemented with a low-noise amplifier of 40.8 dB gain and 200 kHz 3-dB bandwidth
In this paper we report on terahertz detection by field-effect transistors in 65-nm CMOS technology with on-chip integrated patch antennas. In conjunction with continuous wave photomixer source, detectors demonstrate > 40 dB signal-to-noise ratio and minimal NEP of 12~pW/√Hz @1 kHz of chopping at the resonant frequency of 620 GHz. This NEP value by few pW/√Hz lower than best reported values for this category of detectors which gradually approaches the state-of-the-art characteristics of THz bolometers.
The comparison of two full-wave models of photoconductive terahertz antenna is performed. One model solves simple approximation of drift-diffusion equations another uses Monte Carlo simulation for estimation of the electrical current in the active region of antenna. Simulation results revealed that the simple model can be useful in the cases when the duration of photoexcitation is relatively long (FWHM >= 250 fs). In a case of shorter laser pulses and usual electron recombination times in compensated gallium arsenide, transient dynamics of electron drift velocity at sub-picosecond time scales makes significant impact to the growth speed of photocurrent. For this reason, the simple model leads to the overestimation of electric field amplitude in the high-frequency range. Full-wave simulation shows good agreement with experimental results when detectors' response is included in calculation. Calculated results were confirmed experimentally what increases the reliability of the full-wave model presented in the paper.
Photon detectors operating in infrared and terahertz spectral ranges require cryogenic cooling to achieve useful performance. The need for cooling is a major limitation of IR photon detectors what prevents more widespread use of IR technology. At present, uncooled thermal detector focal plane arrays are successfully used in staring thermal imagers. However, the performance of thermal detectors is modest, they suffer from slow response and they are not very useful in applications requiring multispectral detection. Initial efforts to develop high operating temperature (HOT) photodetectors were concentrated on HgCdTe photoconductors and photoelectromagnetic detectors. More recently, technological efforts have been directed on advanced heterojunction photovoltaic HgCdTe detectors. In the paper, a number of concepts to improve performance of photon detectors operating at room temperature are presented. Several types of detector materials are considered: HgCdTe, type-II AIIIBV superlattices, two-dimensional materials and colloidal quantum dots. At present stage of HgCdTe technology, the Rule 07 metric is not a good approach for prediction of HgCdTe detector and system performance and as a reference benchmark for alternative technologies. It is shown that uncooled depletion-limited HgCdTe photovoltaic detector can achieve background limited detectivity in long wavelength infrared spectral range at room temperature. In this context are considered alternative technologies. It is shown that it will be rather difficult to rival 2D material and colloidal quantum dot photodetectors with HgCdTe photodiodes. The above estimations provide further encouragement for achieving low-cost and high performance MWIR and LWIR HgCdTe focal plane arrays operated in HOT conditions.
In this paper, a 2 x 2 antenna array operating at 5.8 GHz is presented for vital signs acquisition using a radar based system, also known as bio-radar. Since these non-contact systems have multiple applications, their front-end design should take into account the monitoring environment of each specific application. In this sense, the antenna design has a crucial role to guarantee the proper integration of the full system, considering different materials. In this work, the antennas were made using upholstery textile materials, in order to integrate the bio-radar system into a car seat cover. This work presents the design of the antenna and the results achieved through measurements in the anechoic chamber.
In the paper, a slot antenna and a Vivaldi antenna are integrated into a technical, three-dimensional knitted fabric. In order to eliminate problematic sewing, side walls of antenna structures are implemented by an artificial magnetic conductor. Hence, the whole antenna structure can be screen-printed using a polymer silver paste. Parameters of the designed antennas were verified by computer simulations.
The paper deals with the development of a wireless charger for small mobile devices (mobile phones, tablets) to be manufactured from a three-dimensional knitted material instead of a common microwave substrate (e.g., FR4). The textile-integrated device is based on the universal Qi standard for wireless charging. Basic attributes of the design are summarized and technological aspects of manufacturing are discussed.
In a presentation, we shall recall about Fano resonance phenomena, make a brief review on Fano resonances found in metasurfaces, and present recently found Fano resonance in a mirrored array of split-ring resonators. It appears due to the direct interaction of lattice and plasmonic modes. The resonance frequency can be changed by changing the period of the array. The high-quality factor of Fano resonance, around 100, has been evidenced experimentally. Possible applications of the Fano resonance will be considered.
The ability to make accurate and repeatable measurements, rapidly and over wide bandwidths, is essential to more widespread use of the sub-millimeter and THz spectrum. This talk gives an overview of the last two decades of advances in this area. We trace the progression from development and construction of the extremely sensitive superconducting heterodyne receivers in the Atacama Large Millimeter Array (ALMA) to the commercial availability of general frequency extension modules for common microwave test equipment up to 1 THz and beyond. We also describe emerging moderate-volume applications for submillimeter-wave and THz sources and receivers, including small satellite constellations for atmospheric modeling and weather forecasting.
The existence of thermal noise in the channel of a MOS field effect transistor was postulated in early work by Klassen and Prinz [1] and since has been wholeheartedly adopted by the CMOS community as a relatively recent review paper clearly indicates [2]. A very similar approach has been adopted by the authors of BSIM series of compact models (for example [3]). However, this approach is not consistent with universally accepted noise models of III-V FETs and HEMT (see for example [4], [5]). In the latter approach, the gate noise behaves as thermal noise while the drain noise reveals behavior consistent with suppressed shot noise [6]. The drain noise is highly suppressed for long gates by a factor of almost 10 while for very short gates the drain noise approaches a pure shot noise [6], [7]. In fact, almost pure short noise has been experimentally observed in 10 nm gate length CMOS devices [8]. A reduction in gate length improves cut-off frequency but also increases drain noise. These two counter-balancing effects explain why for short gate devices expected improvements in MOSFET noise temperatures upon further gate scaling have not materialized. This paper will explore inconsistencies in noise modeling of noise in III-V FETs and MOSFET and it will explain why the noise performance of RF CMOS has reached its natural limits.
This paper presents Electronically Reconfigurable Superstrate (ERES) antenna capable of modifying the shape of the radiation pattern in an uncomplicated way. The approach adopted in this concept is based on switching the state of passive patch elements placed on an additional layer located above a simple microstrip patch antenna. In order to change the area covered by the antenna range, the proposed antenna provides six different configurations with different directions of maximum radiation and various 3 dB antenna beamwidth. The antenna is dedicated to working in the field of Ultra High Frequency (UHF) Radio Frequency Identification (RFID) applications.
Design and numerical characteristics of X-band non-planar full-metal slot reflectarray antenna are presented. The relative bandwidths of 19.6% upon a criteria of 3 dB directivity reduction and 31.2 dB peak directivity are obtained for the proposed reflectarray. The designed reflectarray size is 20λ×20λ and it consists of two panels assembled edge to edge that form non-planar surface. The proposed full-metal reflectarray design allows the use of laser-cutting techniques for antenna manufacturing. Comparison of the proposed non-planar reflectarray with optimized in different frequency range planar ones and a parabolic reflector is carried out.
Low RCS and long range target detection requires larger power aperture product, which can be achieved by phased array antennas with large number of elements. Antennas with Phased arrays with large antenna arrays increases system complexity. Subarray level multibeam architecture with array processing reduces the system complexity and improves the target detection and estimation performance. Subarray configuration plays a vital role in the array processing. In this paper a new framework with multibeam synthesis is proposed along with subarray configuration design methodology. Modified Clustering algorithms are developed to design the optimal subarray configuration. Experiments are conducted with large hexagonal planar array and results are evaluated with several performance metrics to demonstrate the significance of proposed methods
We consider DoA estimation in a monopulse radar system employing a tilted rotating array. We investigate the case of nonzero steering angles, in which case the mapping between the target's azimuth and elevation in the global coordinate system and their counterparts in the array local coordinate system becomes increasingly nonlinear and coupled. Since estimating the azimuth using coherently integrated signals might be difficult because of strong modulation in the difference signal induced by the rotation of the antenna, we develop an iterative approach that alternates between estimating the elevation using coherently integrated signals and estimating the azimuth using unfiltered signals. We also develop a simplified version of the scheme, which employs only one iteration and forms the final estimates by applying simple corrections to results of the first iteration.
Different approaches to development of an auxiliary antenna designated for sidelobe blanking systems are proposed and discussed. In the proposed concepts a set of two antennas having different radiation patterns is utilized in order to ensure good coverage of main radar antenna's sidelobes. The concepts of the auxiliary antenna are evaluated and compared. The results are comprehensively presented and the criteria for selection of the concept are reported.
The innovative concept of nonresonating modes and how this has been exploited to extend the state-of-art of microwave filter technology will be presented in this talk. After a brief introduction highlighting the importance of microwave filters from a system perspective, the main concepts will be gradually explained by using some waveguide as well as planar SIW examples. The general multimode environment of these structures is described step-by-step with several animations, thus significantly easing the understanding of these concepts for both students and non-filter experts. The presentation is then extended to the most various filter technologies, such as conventional coaxial structures, dielectric resonators based architectures, as well as more original mixed technologies. Several manufacturing examples of actual products developed at RS Microwave (Dr Bastioli's affiliation) are going to be presented along this talk, thus also satisfying the more practical taste of an industry audience.
The paper presents a design of broadband coupled-line directional coupler. The wide operational bandwidth has been obtained by the use of a two-section coupler topology. The tight-coupled section has been designed as a section with indirectly coupled conductors, which makes the design easier in comparison the directly coupled multi-conductor lines. The coupler has been designed in a bi-level microstrip technique. Additionally, capacitive compensation has been applied to improve directivity of the coupler.
Novel configuration of the Faraday rotation isolator employing longitudinally-magnetized ferrite coupled line (FCL) is realized by connecting two lines with a resistor at the end of the ferrite section. The scattering parameters of this microstrip structure obtained through circuit and normal mode analysis providing information for practical design of the isolator. The nonreciprocal behavior of the isolator and its dependence on resistor parameters is reported.
In general, a millimeter-wave component is expensive to fabricate, then, it is an entry barrier of small- and medium-sized enterprises to millimeter-wave industries. Thus, we developed an additive manufacturing (3-D printing) technology for a cost-effective fabrication method of waveguide components in W-band. This report explains a fourth-order Chebyshev bandpass filter is fabricated based on polyamide 11 substrate and conventional nickel electroless plating and copper electroplating technology. The filter has a bandwidth of 7.2 GHz and an insertion loss of 1.4 dB at the center frequency of 87.75 GHz. We confirmed the proposed method contributes cost-effective, light-weight, and easy to manufacture millimeter-wave components.
This paper studies an integration concept for a self-biased Ka-band circulator. Non-reciprocity is achieved by means of a pre-sintered scandium substituted barium hexaferrite which, as a hard-magnetic material, does not require external magnetic biasing. The ferrite is integrated into a microstrip circuit on a RO4000 laminate. This yields a compact and potentially low-cost circulator. The basic functionality is demonstrated in a first experiment. The results are still quite preliminary, though. Yet, some important conclusions can be drawn regarding the required design optimization measures.
Electromagnetic (EM) simulation is the single most important tool in the design of modern antenna structures. Its versatility and reliability comes at a price of considerable evaluation cost, which may be impractical or even prohibitive when multiple simulations are to be executed, e.g., pertaining to parameter tuning or uncertainty quantification. Fast replacement models (or surrogates) may mitigate this problem but modeling of antenna characteristics is a challenging endeavor due to their nonlinearity and typically high-dimensionality of the parameter space. Conventional data-driven modeling methods fail under such circumstances. In this paper, a novel technique is presented which combines the nested kriging framework and variable-fidelity computational models. The former is employed to confine the surrogate model domain to a region containing designs that are of high-quality from the point of view of the considered performance figures. This dramatically reduces the number of required training data samples. Incorporation of low- and high-fidelity simulations is realized using co-kriging. The proposed approach is illustrated using a wideband monopole antenna modeled for wide ranges of substrate permittivity (2.0 <= eps <= 5.0) and height (0.5 mm <= h <= 1.5 mm). Benchmarking indicates that constrained variable-fidelity model outperforms both the conventional surrogates but also the constrained surrogate constructed using high-fidelity EM data only.
Electromagnetic (EM)-driven adjustment of geometry parameters, often referred to as design closure, is nowadays a mandatory stage of antenna design process. It is executed to improve the system performance as much as possible while taking into account parameter dependencies that cannot be handled by simpler methods (e.g., theoretical models), typically employed at the initial steps of the antenna development. Unfortunately, EM-based optimization is a time consuming task, especially when the quality of the initial design is poor. This paper proposes a novel framework for accelerated antenna optimization. Our methodology involves a database of previously obtained designs, kriging interpolation models, and an iterative correction scheme for design refinement. The incorporation of pre-existing data permits generation of a good initial design as well as rapid optimization entailing the cost of just a few EM antenna analyses. The technique is demonstrated using a dual-band uniplanar dipole antenna. The structure is optimized within wide ranges of operating frequencies (2 GHz to 3 GHz for the lower band and 4 GHz to 5.5 GHz for the upper band). Benchmarking indicates that the proposed approach exhibits improved computational efficiency and reliability as compared to gradient-based warm-start optimization techniques.
Main advantages of employing DVB-S as Illuminator of Opportunity for passive radar is high availability, but the power scattered from targets is really low. In this paper, the design of a surveillance antenna capable of fulfilling the requirements defined by the DVB-S passive radar, is carried out. Detection and tracking capabilities of ground targets are considered. A high gain antenna is required for fulfilling range coverage requirements, together with an azimuth beamwidth that provides the required angular one.
To tackle this challenge, a sectorial beam reflectarray antenna is selected. For designing it, a method based on optimizing the steering of a set of beams that form of the sectorial pattern is proposed. The losses from reflectarray cells are introduced, optimizing the distribution of elements by selecting the best phase for the central one. The reflectarray is designed studying the geometric and feeding parameters and it is simulated in ANSYS HFSS achieving a sectorial beam of 7.8º (azimuth) x 2.6º (elevation) with a gain of 28.5 dBi.
This paper presents a design of a millimeter wave (mm-wave) transmitting device, which integrates components fabricated in various technologies. It is composed of a transmitter front-end integrated circuit, an antenna array, and a silicon lens. The design is outlined with particular emphasis on accommodation of contrary requirements of individual elements and integration of the antenna array with other parts of the circuitry into a single device. The low temperature cofired ceramics (LTCC) multilayer structure was chosen as a platform for integration. LTCC demonstrates good electrical parameters (low losses and relatively low permittivity) in the mm-wave range which facilitates design of an efficient antenna. Additional beam focusing and the gain enhancement is achieved by means of the silicon lens suspended over the antenna on an adjustable fixture. The problem of optimal lens placement for two types of antennas is considered.
In this paper two versions of miniaturized 3D printed, open-ended, ridge waveguide antennas are presented. The air-filled and dielectric-filled antennas have been designed, simulated and measured. Several copies of antennas have been manufactured to investigate the impact of dimensions inaccuracy of 3D-printing technology on return loss parameters. For dielectric-filled antenna tuning process is proposed in order to reduce the impact of printed material permittivity and dimensions spread.
A combination of the body-of-revolution and finite element methods is utilized to the analysis of coaxial lines with corrugated rod and wall. Both periodic and non-periodic structures can be investigated. As the structure is axially symmetrical the two dimensional scalar-vector finite element method can be used, which allows for the investigation of complex geometries and is computationally efficient. A generalized impedance matrix at the line ports is calculated from which the scattering parameters are derived. A few examples of corrugated coaxial lines have been analyzed and the results were compared to those obtained from commercial software.
In this paper, a method of analysis of conformal RF components has been proposed. In this approach, modeling of a curved structure is based on mesh deformation of planar objects rather than the construction of conformal geometry at CSG level. Since the model is represented as a 3D mesh, the deformation only requires the calculation of nodes position in the bent structure. The results of the proposed algorithm have been validated with simulation from other software and measurements, whereby method correctness has been confirmed.
Measurements of electric and electromagnetic field for safety controls are made by E field probes, typically with scaling in power flux density, indicating what would be true only for plane propagating waves. This presentation addresses the fact that such measurements at microwave frequencies have to be at a minimum distance from the nearest accessible part of the equipment emitting the field, and describes the different rationales for the validity of the 50 mm distance used since many years with e.g. microwave ovens and industrial equipment. -- Since the emission of electric field energy dominates over that from the magnetic field in high frequency equipment, almost quasistatic E field emission conditions occur, resulting in a much weaker power absorption in human tissues than assumed in the existing safety standards. The phenomena are quantified, and a relaxation of the E field emission limits in industrial standards is proposed for such non-radiating conditions, as is a 150 mm minimum measurement distance in combination with barriers, etc., hindering access.
In this work, an anisotropic FDTD method is introduced to simulate electromagnetic concealment with metamaterials using transformation optics. The theory of the algorithm is derived to support our freely available FDTD code, in MATLAB environment. The algorithm provides the possibility to simulate the transient behavior of the electromagnetic cloaking device. The calculation of the anisotropic material properties of the electromagnetic cloak is reviewed.
Dielectric characterization of materials with a Fabry-Perot open resonator in microwave and millimeter wave frequency bands has been known for decades. However, recent rapid development of 5G telecommunications has prompted attempts to extend its applicability toward higher frequencies, and samples with larger thickness and higher permittivity. It requires, among other things, an accurate electromagnetic model of the resonator, which could account for effects that are not occurring in case of thin low-permittivity samples that have been measured so far. For that purpose, a general concept of the analysis of a Fabry-Perot open resonator with the aid of a plane wave expansion method, which opens the way for rigorous, versatile and computationally effective modelling with the measured samples of any kind, is proposed in this paper.
A combination of mode matching, finite element methods and generalized impedance matrix is presented in a context of propagation problems for open guiding structures. The computational domain is divided into two regions: the first one is a circular cylinder containing whole guiding structure and the second one surrounds this artificial cylinder. The impedance matrix is calculated with the use of finite element method in the first region and fields outside are expressed by analytical functions. As a last step propagation coefficients are obtained with the use of global roots and poles finding algorithm. The results for simple dielectric ridge waveguides are presented and compared with alternative solutions.
This paper presents a new approach to plane wave injection in FDTD, which is based on total-field/scattered field (TF/SF) formulation. Six-faced box is used to ensure appropriate boundary conditions for injected plane wave. In relation to TF/SF and G-TF/SF methods, in the proposed approach a number of utilized TF/SF faces is reduced from 6 to 1-3, depending on direction of wave vector of the generated plane wave. Such an approach provides a significant gain in computer resources required for simulation.
In this paper hybrid method for electromagnetic (EM) modelling of coherent radiation in semiconductor lasers is presented. Described approach consist of drift diffusion (DD) model and electromagnetic simulation. Four-level two-electron atomic system with Pauli Exclusion Principle (PEP) extended by electric pumping ratio has been used as lasing model.
The paper presents an open access software platform for electromagnetic (EM) teaching and dissemination of microwave technology results. The platform is developed within the H2020 MMAMA project. Its core is a licence-free GUI, wherefrom different EM and multiphysics solvers can be launched, under different licence schemes. The tools are supplemented with an expandable database of modelling examples and results, documented in the standardised MODA and Gwyddion formats. The presented examples range from the Basic Microwave Course, whose elements have been used for 25 years in teaching at the Warsaw University of Technology, to the modelling of calibration standards for microwave microscopy of materials.
Dorota Myko Faculty of Electronics and Information Technology Warsaw University of Technology dorota.myko@gmail.com
We would like to invite all the participants of the conference to join the presentation about emotions in our life, and how to deal with them and as a result manage stress.
Emotions are states connected with pleasure or unpleasantness. They are also reactions to the positive or negative stress. We can describe emotions of human beings and animals, and perhaps - also plants.
In general, it is common to believe negative emotions are bad, but we shouldn't forget that they have also positive energy. If our different needs are not fulfilled from the early childhood we don't have the mechanism to develop many emotions at certain level. That could lead us to various psychical and physical illnesses and as a consequence to shorter life expectancy . Therefore it is very important to form our psychological resiliency to stres. That is why special Ego Resiliency Scale was created by Block and Kremen in 1996. Moreover the mechanism of the positive desintegration described by Kazimierz Dąbrowski enriches all human life and broadens horizons of thinking and feeling and can become the inspiration to the creativity in different domains.
The research on Mirror Neurons by Giacomo Rizzolatti is vital in the process of emotion's "contamination". Nowadays, due to the technical progress, many various experiments in this area are carried out with the help of optogenetics e.g. by Phd. Ewelina Knapska from Nencki Institute.
Emotions can cause psychosomatic illnesses, addictions and anyone can be object of manipulations because of emotions. We would like emphasize that the appropriate diet and exercises help us to deal with emotions and influence our behavior in a positive way.
For everybody who is interested in the article in Polish and in English and in the bibliography the materials are disponible - write please at e-mail: dorota.myko@gmail.com
Dorota Myko graduated from Warsaw University with a master's degree of Librarianship, then did two postgraduate studies: at Paris-Nord University XIII - Publishing Studies and at Warsaw School of Economics (SGH) in cooperation with Haute Ecole de Commerce (HEC, France) - Masters of European and Industrial Marketing and Management. Between 2003-2015 she was Polish representative of the global conference Online Educa Berlin. Since 2005 she has been working at Warsaw University of Technology at the Faculty of Electronics and Information Technologies in the Department of Promotion and Information.
Dorota Myko's hobby was, between 2013 and 2016, ceramics, then since 2017 she has been involved in graphics (linocut). In March 2020 she has started to do watercolors.
We would like to invite all the participants of the conference to join the presentation about emotions in our life, and how to deal with them and as a result manage stress.
Emotions are states connected with pleasure or unpleasantness. They are also reactions to the positive or negative stress. We can describe emotions of human beings and animals, and perhaps - also plants.
In general, it is common to believe negative emotions are bad, but we shouldn't forget that they have also positive energy. If our different needs are not fulfilled from the early childhood we don't have the mechanism to develop many emotions at certain level. That could lead us to various psychical and physical illnesses and as a consequence to shorter life expectancy. Therefore it is very important to form our psychological resiliency to stres. That is why special Ego Resiliency Scale was created by Block and Kremen in 1996. Moreover the mechanism of the positive desintegration described by Kazimierz Dąbrowski enriches all human life and broadens horizons of thinking and feeling and can become the inspiration to the creativity in different domains.
The research on Mirror Neurons by Giacomo Rizzolatti is vital in the process of emotion's "contamination". Nowadays, due to the technical progress, many various experiments in this area are carried out with the help of optogenetics e.g. by Phd. Ewelina Knapska from Nencki Institute.
Emotions can cause psychosomatic illnesses, addictions and anyone can be object of manipulations because of emotions. We would like emphasize that the appropriate diet and exercises help us to deal with emotions and influence our behavior in a positive way.
This paper reports the design, manufacturing and test of a power amplifier, based on a newly power bar device developed on GaN technology, conceived for L-Band applications. The realized active device is a single 10mm active periphery GaN HEMT, realized by paralleling eight 1.25 mm-gate periphery devices (10x125μm), fabricated on a 0.5μm GaN-on-SiC technology by Leonardo company. The power amplifier realized with this device is tested in pulsed condition, demonstrating an output power higher than 40W at 30V of drain voltage supply, with an associated efficiency of 50% at 3 dB of gain compression.
In the paper RF performances and thermal features of GaN HEMTs grown on Si substrate for the design of microwave high-power amplifiers have been briefly presented referring also to the state of the art of the dominant GaN-on-SiC HEMT technology. As GaN-on-Si HEMT application examples driver and final stage amplifiers with high-voltage NPT2018 and NPT2022 transistors made by MACOM were designed and experimentally verified. The amplifiers operate over a 1.2 GHz to 1.4 GHz frequency range with saturated output power nearly 42 dBm and 51 dBm, respectively, at the power added efficiency more than 60%.
This paper presents a wideband class J power amplifier (PA) based on a packaged 10 W GaN HEMT device covering the 3 GHz to 3.8 GHz frequency range. A good trade-off between efficiency and gain has been pursued in synthesizing the second harmonic output termination. The achieved output power is in excess of 41 dBm with drain efficiency ranging from 59 % to 65.5 % and a small signal gain above 14 dB. Preliminary large signal measurements at 3.3 GHz confirm the proper behavior of the PA.
This paper presents a design of highly efficient 3 way Doherty amplifier with CG2H40010 transistors from Wolfspeed. A new power divider is presented that enables the compact Inverted 3-way Doherty architecture to be designed. The amplifier operates over a 3.4 to 3.8 GHz frequency range and reaches up to 46W of saturated output power with drain efficiency of 75% at full drive and 53% at 10dB output power back-off.
This paper presents a Doherty power amplifier working from 3.1 GHz to 3.6 GHz. It adopts 10 W packaged GaN HEMTs from Cree/Wolfspeed and achieves a saturated output power in excess of 43.4 dBm. Saturated efficiency ranges from 57.7 % to 75.2 %, while efficiency at 6 dB back-off is between 44.2 % and 59.8 %. System-level simulations at 3.5 GHz adopting a 16QAM signal with 5 MHz bandwidth and 4 dB PAPR showed an adjacent channel power ratio of -28 dBc/Hz without pre-distortion, at an average output power of 43 dBm and with an average efficiency of 71 %.
As antenna arrays are being deployed in both 5G base-stations and user equipment, phase-shifters have received great attention. This work reviews the requirements for phase-shifters in 5G user equipment and presents ultra-broadband phase-shifting solutions capable of complete coverage of 5G millimeter-wave spectrum.
In this paper an example of the high power diplexer for the phase reference line in proton accelerator is presented. The diplexer operates at frequency 352 MHz and 704 MHz. The output power level is 200 W. Additionally the requirements for the slope of the diplexer phase characteristic have been set at low level. The diplexer consists of two filters realized in the microstrip line technology. To improve the diplexer characteristics a special method has been used in the design. The inverters in the lower frequency passband filter have different electric lengths. The measurements show the low loss, high isolation of transmission bands and phase stable in the passbands thus confirm applied method.
RF SplitBox is a 10-channel signal distribution module designed for use in LLRF control system of the European Spallation Source accelerator. It is designed in two variants, operating at different signal frequencies: 352.21 MHz and 704.42 MHz. The device is constructed from several submodules. Their design is discussed in this paper, with main focus on low-loss and low phase drift RF power splitter circuits. Low phase drift in signal distribution modules is essential for achieving and maintaining required beam parameters in the accelerator. RF SplitBox prototype measurement results are presented.
Crosstalks are one of the limitations of multichannel RF systems. An example of such is the Cavity Simulator project designed by the Institute of Electronic Systems to be used for testing the Low-Level Radio Frequency (LLRF) control system in the European Spallation Source (ESS) in Lund. This device contains 7 RF outputs interfering with each other, resulting in a limited dynamic range.
To resolve the issue of crosstalk, a solution, where a pre-distortion signal is added to all channels, was proposed. The concept was tested, but the solution required manual reconnecting of RF cables and took a significant amount of time. Based on the first results, a solution with automated signal switching was proposed. It is based on an additional module that is integrated with the Cavity Simulator hardware.
This paper present the proposed solution for the RF front-end used in the automated crosstalk correction system for the Cavity Simulator project. The overall system concept and the detailed design of the crosstalk correction module are shown.
This document presents a realization of an analog voltage driven 3 GHz phase shifter circuits for the phase reference distribution system (PRDS) that is currently under development by the Institute of Electronic Systems (ISE) for SINBAD (Short Innovative Bunches and Accelerators at DESY), in Hamburg. Presented phase shifter structure is based on a topology of a reflection phase shifter, made with a 3 dB hybrid coupler structure and varactor diodes acting as adjustable reflections. The realization is planned to be used as a substitute for obsolete phase shifter ICs and for this reason the area taken by the phase shifter in the PCB should be small. That is why we decided to use commercially available LTCC hybrid couplers, which allow widening the frequency band that can be covered by the phase shifter, area reduction and maintaining good return loss and insertion loss of the device, which is of utmost importance in SINBAD PRDS.
Modern linear particle accelerators are large-scale facilities utilizing normal and superconducting microwave resonator cavities to increase energy of physical particles such as electrons or protons. Particles travel at velocities comparable to the speed of light through the cavities and high-gradient Electro-Magnetic fields must be extremely precisely amplitude and phase controlled in order to assure proper acceleration of the particle beam. Sophisticated accelerating field controllers and beam diagnostic systems require synchronization reaching tens of femtoseconds in time domain or 0.001 degree in phase at RF frequencies. In larger accelerators like the E-XFEL in Hamburg, there are several thousands of synchronized devices distributed along 3,4 km long machine. This talk will cover challenges and solutions used to distribute RF synchronization signals in large scientific machines, including control of phase noise and phase drift in components of the synchronization system.