Availability of Wireless Fading Channel Under Outage State with Tolerance Time
David Al-Dabass (Nottingham Trent University, United Kingdom (Great Britain))
Analytical models are often developed to characterize probabilistic behavior of wireless channels using Finite State Markov (FSM) model approach. The paper presents Outage Tolerant FSM (OTFSM) channel model based on maximum acceptable 'Tolerance time'. These are the short outage times, a wireless channel can tolerate without compromising telecommunication system quality in terms of acceptable Bit Error Rate (BER). The model is used to estimate channel availability and its further improvement with tolerance time. The rationale of the tolerance time threshold with error correction capability is also discussed. Constant and arbitrary distributed tolerance time is considered in model development and is applied over wireless channel. Further fading parameters of the wireless channel such as Average Fade Duration (AFD), frequency of outage and probability of outage are derived in terms of tolerance time. The case study demonstrates the improvement in channel availability by eight to ten percent with tolerance times of approximately one forth of estimated AFD. The proposed methodology will help in efficient characterization of the fading channel which can be used in deciding error correction codes to alleviate the multipath effects and to evaluate performance of the wireless system including higher order protocols.
Journal: International Journal of Simulation- Systems, Science and Technology- IJSSST V12
Published: Feb 28, 2011