Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí sinh học đề tài : Performance analysis of MIMO-SESS with Alamouti scheme over Rayleigh fading channels | Ma et al. EURASIP Journal on Wireless Communications and Networking 2011 2011 145 http content 2011 1 145 o EURASIP Journal on Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Performance analysis of MIMO-SESS with Alamouti scheme over Rayleigh fading channels Shichuan Ma Lim Nguyen Yaoqing Lamar Yang and Won Mee Jang Abstract Self-encoded spread spectrum SESS is a novel modulation technique that acquires its spreading sequence from the random input data stream rather than through the use of the traditional pseudo-noise code generator. It has been incorporated with multiple-input multiple-output MIMO systems as a means to combat fading in wireless channels. In this paper we present the analytical study of the bit-error rate BER performance of MIMO-SESS systems under Rayleigh fading. The BER expressions are derived in closed form and the veracity of the analysis is confirmed by numerical calculations that demonstrate excellent agreement with simulation results. The performance analysis shows that the effects of fading can be effectively mitigated by taking advantage of spatial and temporal diversities. For example a 2 X 2 MIMO-SESS system can achieve about 7 dB performance improvement at 10-4 BER over a MIMO PN-coded spread spectrum system. Keywords self-encoded spread spectrum iterative detection multiple-input multiple-output Alamouti scheme 1 Introduction Conventional direct sequence spread spectrum system employs pseudo-noise PN code generators which are typically linear feedback shift register circuits that generate maximal length or related sequences. In contrast by deriving its spreading sequences from the user data stream and obviating the need for PN code generators self-encoded spread spectrum SESS provides a feasible implementation of random-coded spread spectrum and has a number of unique features such as the potential for enhanced transmission security and anti-jamming capability multi-rate .
