HYBRID MULTILAYER SCHEMES FOR ACHIEVING THE MAXIMUM POSSIBLE DIVERSITY GAIN

This paper proposes a novel signal scheme called “Hybrid BLAST STBC approach” this combines MIMO (multiple-input multiple-output) and STBC (space time block code) to generate a system functionally superior to MIMO and STBC systems. This paper compares and investigates the capacity of high data rate wireless local area network systems using MIMO techniques. In particular, two different algorithms-V-Blasts and STBC, are described. A third hybrid approach, which incorporates elements of both V-BLAST and STBC (Hybrid BLAST STBC), is also introduced. The focus of the study is to compare the information capacity of hybrid systems with V-BLAST and STBCs. Hybrid can balance transmit diversity gain and spatial multiplexing gain. All three techniques are compared using both theoretical Shannon capacity analysis and by simulation results for the bit error ratio and capacity performance of the three methods. The result of this study shows that hybrid method attains superior diversity gain performance to V-BLAST and can out form V-blast at spectral efficiencies of practical interest. Furthermore, at low SNRs and low outage probabilities, hybrid is more spectrally efficient. Thus, it is more suitable for low power high data rate wireless applications. Finally, we compare the performance of our proposed system with the conventional scheme by computer simulations which validate the analytical results.