Performance Analysis of Weighted Space Time Trellis Codes

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 multipleinput multiple-output systems has acquired a great interest in recent years. One of the major problems that wireless communication systems face is multipath fading.Diversity is often used to overcome this problem. There are three kinds of diversity - spatial, time and frequency diversity. Space-time trellis coding (STTC) is a technique that can be used to improve the performance of mobile communications systems over fading channels. It is a combination of space and time diversity. In this paper, we’ll review about STTC and different diversity schemes.