Simulation on performance of space time block code

In a wireless communication system, time-varying multipath fading has become the main constraint that affects the reliability of a wirelesssystem. The most effective technique that had been used to mitigate the multipath fading is diversity. Space time block coding (STBC) offers the diversity technique and uses multiple-input and multiple output (MIMO) concepts in order to overcome the problem of fading and interference in a wireless communication system. The use of antenna arrays at both transmitter and receiver for a MIMO system gives benefits in terms of rate and reliability. Therefore, this paper analyzes the capability of STBC to minimize the fading effect and also improve the capacity.

Three simulation models have been developed using Matlab V 6.5 software. The MIMO capacity measurement is also analyzed using the same software. The designed models then have been simulated with different numbers of code rate and antenna. The proposed STBC in this thesis consists of interleaver and cyclic code with code rate 4/5, 4/6 and 4/7. The simulation model is then sent through an AWGN channel to analyze the performance in terms of BER. The simulation results show that the proposed 2 transmitter and 2 receiver antenna model improved 90% of BER and 73% capacity compared to the conventional one antenna system.