Weighted Multilevel Space-Time Trellis Codes for Rayleigh Fading Channels

Abstract

Wireless communications have been developed widely and rapidly in the modern world especially during the last decade. Recent advances in wireless communication systems have increased the throughput over wireless channels. The reliability of wireless communication has also been increased. But still the bandwidth and spectral availability demands are endless. The need to achieve reliable wireless systems with high spectral efficiency, low complexity and good error performance results in continued research in this field. The research in the field of space-time coding and multiple-input multiple-output systems has acquired a great interest in recent years. In this thesis we present the concept of weighted multilevel space-time trellis codes. These codes are a combination of multilevel space-time codes and ideal beamforming. It has been shown that if perfect channel state information is available at the transmitter, the performance of a space-time coded system can be further improved by weighting the transmitted signals. In this thesis, we evaluate the performance of multilevel space-time trellis codes combined with ideal beamforming over slow fading channels. Simulation results show that the proposed scheme considerably outperforms the conventional multilevel space-time trellis without weighting.