说明：  在AWGN信道模型下，对比ACO-OFDM和其他调制方式对光纤通信系统性能，将ACO-OFDM与一些调制技术相结合来进一步提高系统宽带效率、降低光发送功率等，以提升光纤通信系统的性能
(In AWGN channel model, compared to ACO-OFDM and other modulation schemes for optical fiber communication system performance, the ACO-OFDM with some modulation techniques combined to further improve the system broadband efficiency and reduce light transmission power so as to enhance the performance of optical fiber communication systems)