Performance analysis of Diversity Techniques and amplify and forward wireless relay networks in multipath fading channels

In this paper, bit error rate (BER) analysis of Diversity Techniques and amplify and forward (AF) wireless relay networks (WRN) in various multipath fading channels is addressed. Transmit diversity and Receive diversity techniques are considered and finally extended to multiple input multiple output (MIMO) systems. Normally Rayleigh distribution is employed to model short term fading statistics in high frequency (HF) applications. But when fading is severe in applications like long distance HF communication links Nakagami distribution can be employed and Rician distribution can be used in scenarios where there is line of sight (LOS) communication. Simulation results are obtained in Rayleigh, Rician and Nakagami flat fading channels to characterize BER performance of Diversity Techniques. Moreover, the main contribution of this paper is best linear unbiased estimation (BLUE) based BER analysis of AFWRN in Rayleigh flat fading channel environments. Eventhough, BLUE is an existing algorithm when applied for AFWRN, simulation results signify that BLUE based BER analysis is better than traditional least squares (LS) and minimum mean square error (MMSE) based BER performance since BLUE has minimum variance characteristic. Results obtained can act as a benchmark for analyzing BER performance of Diversity Techniques and amplify and forward wireless relay networks.