DESIGN AND PERFORMANCE EVALUATION OF SUPER-ORTHOGONAL SPACE-TIME TRELLIS CODES

Abstract

With the rapid development of wireless communications, the available bandwidth for wireless applications becomes more and more insufficient. Therefore, to improve data rate without expending bandwidth becomes a main goal in modern communication system design. Recently, two wireless communication schemes, which can be used to effectively combat with multi-path fading, are widely investigated around the world. One is the multiple-input multiple-output (MIMO) technology and another is the space-time coding (STC). As a result, a combined system, MIMO-STC, can be used for wireless communications to jointly explore the advantages of the above two strategies. In the study of MIMO-STC systems, the space-time block codes (STBC) and the space-time trellis codes (STTC) are two efficient coding approaches. The former can be used to offer a full diversity gain, and the later can provide the systems with a large coding gain. Since 2003, -super-orthogonal space-time trellis codes (SOSTTC) a new coding method processing the merits of both STBC and STTC, have been developed. In this dissertation, S.OSTTCs scheme along with MPSK constellation are used for high speed wireless communications of a MIMO-STC system. To examine the performance of the proposed SOSTTC system based on the optimal design of set partitioning for BPSK, QPSK and 8-PSK modulation schemes. In simulations, the frame error rate (FER) versus the received SNR performance results show that SOSTTCs have better coding gain than that of the corresponding STTCs. The decoding complexity of SOSTTC is lower than the decoding complexity of STTC. . According to the above results, as the number of states of SOSTTCs increases their performance improves, and the decoding complexity becomes higher .Coding gain distance (CGD) is a good indicator of performance for a large number of receive antenna [18]. 11