Abstract:
Multiple–Input Multiple Output (MIMO) antenna architecture has the ability to increase capacity and reliability of a wireless communication system. Orthogonal Frequency Division Multiplexing (OFDM) is another popular technique in wireless communication which is famous for the efficient high speed transmission and robustness to frequency selective channels. Therefore the integration of the two technologies probably has the potential to meet the ever growing demands of future communication systems. MIMO-OFDM technology is the trend of the next generation WLANs, because of the demand of the higher transmission data rate and better transmission quality. Due to the aforementioned merits of these two techniques, this paper is based on MIMO-OFDM system. It has investigated the performance of MIMO-STBC system. Maximum likelihood decoding is achieved in a simple way through decoding of the signals transmitted from different antennas rather than joint detection. This uses the orthogonal structure of the space–time block code and gives a maximum likelihood decoding algorithm which is based only on linear processing at the receiver. In the first part, the STBC system was calculated for different antenna configuration using simulation software for different modulation schemes. The result proved that the reliability of the wireless link increase as the number of transmits and received antenna increases. At the next stage the performance of MIMO-OFDM system was investigated both with STBC and Convolution coding with the significant improvement of performance.
