Performance analysis of STBC-OFDM wireless communication system with carrier frequency offset

Abstract

The demand for high-speed mobile wireless communications is rapidly growing. OFDM technology promises to be a key technique for achieving the high data capacity and spectral efficiency requirements for wireless communication systems of the near future. Because of the demand of higher transmission data rate and better transmission quality, the STBC-OFDM technology is the trend of the next-generation WLANs and wireless communication. In this thesis, we analyze the symbol error performance of a STBC-OFDM wireless communication system. Analysis is also extended to include the effect of carrier frequency offset. Theoretical analysis is carried out to evaluate the symbol error performance of STBC ---coded wireless communication system. The performance is compared using Alamouti-STBC and maximal-ratio receive combining scheme. The impact of carrier frequency offset on STBCcoded OFDM systems is also analyzed for BPSK, QPSK and 16-QAM modulation. The performances of STBC-OFDM system in Rayleigh a channels are evaluated with different values of carrier frequency offset. The SER performance of a orthogonal STBC-OFDM with carrier frequency offset with multiple transmitting and single receiving antennas are analytically developed using Gaussian approximation method and Exact method by assuming the ICI to be Gaussian and non-Gaussian. The performance of STBC-OFDM system with carrier frequency offset is also compared with this two method. The results show that the reliability of the wireless communication system increases as the number of transmits and received antenna increase with the use of STBC coding even under frequency offset. The performance results of the system are evaluated by numerical computation and by simulation using MATLAB. The improvement of the system performance due to STBC and performance degradation due to carrier frequency offset is found.