MIMO system performance using various modulations under different channels with STBC, ZF and MRC

In commercial wireless communication systems, higher data rates and reliable communication is required. The challenge in system design is the multipath fading which results in weak signal strength at the receiver, this increases the Bit Error Rate (BER) of Communication Systems. Employing multiple antennas is used to get reliable performance through diversity and achievable higher data rate through spatial multiplexing. Multiple Input Multiple Output (MIMO) systems are wireless Technology with multiple antenna elements at both ends of the link to transfer more data at the same time since fading for each link is considered to be independent and have the ability to deal with multipath propagation. This paper deals with BER analysis of MIMO Systems under different communication channels Additive White Gaussian Noise (AWGN) and Fading channel (Rayleigh and Rician). MIMO system uses Zero Forcing (ZF) decoder and Maximal Ratio Combining (MRC) at the receiver and encoded Alamouti STBC is used as transmit diversity. System performance in diverse modulation techniques such as BPSK, QAM and PAM is examined using MATLAB. The simulated result shows that comparing the three different channel conditions, Rician fading channel has better performance.