Bit Error Rate Performance Analysis of Different Diversity Techniques for various Channels and also modeling the channel effect

Signal fading is a large problem in the wireless communication system. In wireless communication the requirements of high data rate, high signal power, and link reliability call a new technique i.e. MIMO system which satisfies the above requirements and minimize signal fading. MIMO system uses multiple antennas at both transmitter and receiver. MIMO system achieves slight capacity gain and diversity gain than conventional single antenna system. In this paper we have constructed four different MIMO channels of different sample time, different frequency, different path delay and different path gain. we also compare the BER for different transmit diversity vs. receive diversity technique for this four MIMO channels. We also model the channel effect i.e. how the signal fading is randomly changed when an input signal passes through different constructed MIMO channels. The MIMO channel is the frequency selective Rayleigh channel. We also conclude for which channel and diversity technique BER is minimum. Here we have used BPSK digital modulation technique. For simulation we have used MATLAB 2009b software.