Performance Evaluation for V-Blast MIMO Systems under Various Modulation Schemes Using Ricean Channel

Wireless communication using Multiple Input Multiple Output (MIMO) systems increases spectral efficiency for a given total transmits power. Wireless communication technology has shown that the application of multiple antennas at both transmitter and receiver sides improve the possibility of high data rates through data rates through multiplexing or to improve performance through diversity compared to single antenna systems. In this article, we studied the BER performance of Vertical Bells Lab Layered Space Time Architecture (V-BLAST) [2] Spatial Multiplexing Technique with various decoding techniques like Maximum Likelihood (ML), Minimum Mean Square Error (MMSE), Minimum Mean Square Error + Ordered Serial Interference Cancellation (MMSE+OSIC), MMSE, Zero Forcing, Zero Forcing + Ordered Serial Interference Cancellation (ZF+OSIC) by using different modulation techniques such as BPSK, QPSK, 16-QAM in independent, identically distributed (i.i.d) flat fading channel. In this also we will consider a point to point MIMO communications with ‘N’ transmitting antennas and ‘M’ receiving antennas (M≥N). In this article we will compared a different detection techniques with different modulation techniques and finally we will concluded that Maximum Likelihood (V-BLAST ML) decoding technique using BPSK modulation scheme gives better result, QPSK modulation gives almost similar results as BPSK and also we concluded that BER performance of 16-QAM Modulation scheme gives worst result than other modulation techniques in Ricean Channel. Finally we will conclude that ML-VBLAST decoding technique gives the better performance than other decoding techniques using BPSK modulation. Further simulation results for BPSK modulation with only ML decoding technique using various antennas at input and output using rician channel. In this we got more optimal result for 1× 4 antennas for V-BLAST system in rician fading channel.