【摘 要】
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A direct detection optical orthogonal frequency division multiplexing (DDO-OFDM) system using turbo codes is built, and the transmission performance comparison between coded system and uncoded system is analyzed. Three decoding algorithms, which are Log-m
【机 构】
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KeyLaboratoryofFilmElectronicsandCommunicationDevicesandKeyLaboratoryofIntelligentComputingandNovelS
【出 处】
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OptoelectronicsLetters
论文部分内容阅读
A direct detection optical orthogonal frequency division multiplexing (DDO-OFDM) system using turbo codes is built, and the transmission performance comparison between coded system and uncoded system is analyzed. Three decoding algorithms, which are Log-maximum a posteriori (MAP), Max-Log-MAP and threshold Max-Log-MAP, are used in the turbo coded system. By comparing three decoding algorithms, the system using Max-Log-MAP algorithm has the best bit error rate (BER) performance. At the transmission distance of 240 km, the uncoded system with transmission rate of 30 Gbit/s can get the BER performance at the degree of 8.93×10-3with optical signal to noise ratio (OSNR) of 24 dB, while the turbo coded system with transmission rate of 50 Gbit/s can achieve it within OSNR of 20 dB.
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