单边带OFDM-ROF系统中的色散补偿问题研究

Study on effect of dispersion compensation on transmission of ROF-OFDM system in single sideband

建立基于相位调制的单边带光载OFDM-ROF传输系统的仿真模型,分析和仿真光纤色散对OFDM信号传输性能的影响。OFDM信号在较短和较长距离的下行链路传输时,采用相位均衡技术来补偿各个子载波的相位偏转,采用接入色散补偿光纤模块技术降低色散对系统的传输性能的影响,利用色散补偿光纤与标准单模光纤按照长度为1:4的组合方式构成光纤传输链路的补偿方案。研究结果表明:采用相位均衡技术和接入色散光纤模块补偿技术使系统接收到信号的星座图更加紧凑和清晰,从而提高系统对信号接收识别的灵敏度,系统获得了较好的性能增益,增加了下行链路中信号的传输距离和传输质量。

The OFDM-ROF（orthogonal frequency devision multiplexing-radio-over-fiber） transmission system simulation model based on the phase modulation in single sideband was built. The factors of affecing the transmission performance of OFDM signal such as fiber dispersion were analyzed and simulated. When the OFDM signal transmitted in the downlink of the shorter and longer distance, phase equalizer technology and access dispersion compensation fiber module technology were used to reduce the dispersion effects on transmission performance of the system.The use of dispersion compensating fiber single-mode fiber in accordance with the standard 1：4 combinations constituted compensation package fiber transmission link to reduce the dispersion of the transmission performance of the system. The results show that the constellation diagram of the received signal after the dispersion compensation or the phase equalizer technology is more compact and clear. Dispersion compensation technology and phase equalizer technology enables the system to obtain more performance gain.