In this paper,the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing(CO-OFDM) system.RS(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo conca...In this paper,the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing(CO-OFDM) system.RS(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo concatenated code.Two decoding algorithms,which are Max-Log-MAP algorithm and Log-MAP algorithm,are adopted for Turbo decoding,and the iteration Berlekamp-Massey(BM) algorithm is adopted for RS decoding.The simulation results show that the bit error rate(BER) performance of CO-OFDM system with RS-Turbo concatenated code is significantly improved at high optical signal to noise ratio(OSNR),and the iteration number is reduced compared with that of the Turbo coded system.Furthermore,when the Max-Log-MAP algorithm is adopted for Turbo decoding,the transmission distance of CO-OFDM system with RS-Turbo concatenated code can reach about 400 km without error,while that of the Turbo coded system can only reach about 240 km when BER is lower than 10^(-4) order of magnitude.展开更多
基金supported by the National Natural Science Foundation of China(No.61107052)Tianjin Natural Science Foundation of China(No.11JCYBJC0010)Tianjin Youth Foundation of China(No.13JCQNJC01800)
文摘In this paper,the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing(CO-OFDM) system.RS(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo concatenated code.Two decoding algorithms,which are Max-Log-MAP algorithm and Log-MAP algorithm,are adopted for Turbo decoding,and the iteration Berlekamp-Massey(BM) algorithm is adopted for RS decoding.The simulation results show that the bit error rate(BER) performance of CO-OFDM system with RS-Turbo concatenated code is significantly improved at high optical signal to noise ratio(OSNR),and the iteration number is reduced compared with that of the Turbo coded system.Furthermore,when the Max-Log-MAP algorithm is adopted for Turbo decoding,the transmission distance of CO-OFDM system with RS-Turbo concatenated code can reach about 400 km without error,while that of the Turbo coded system can only reach about 240 km when BER is lower than 10^(-4) order of magnitude.
