Performance Comparison of large MIMO Systems using Quasi orthogonal space time block coding through AWGN and Rayleigh Channels by Zero Forcing Receivers

QOSTBC stands for Quasi-Orthogonal Space time block codes that are fully orthogonal and this approach use at the place of previous block code that is OSTBC. QOSTBC design to obtain complete rate because it consisting complex symbol terms in the code structure but it has disadvantage that is reduction of diversity gain and completion in decoding side. Complexity is increases in decoding side, due to the occurrence of interference from the multiple copies of symbols. In this paper Quasi-orthogonal transmission matrix are generate that helps to achieve full rate, and improved diversity gain for the performance of signal to noise ratio verses BER. This performance has been done over AWGN and Rayleigh channels for different scales of PSK scheme. Simulation results illustrate that this scheme enhance the better performance as we go increasing receiving antenna configurations in terms of BER.