Abstract: An optical communication method and system with high spectral efficiency and low power consumption based on joint channel coding modulation relates to the technical field of high-speed fiber communication. The method includes a data acquisition step, a symbol multiplexing joint channel coding modulation step, a signal optical communication step, a channel equalization step, and a symbol demultiplexing step. The optical communication method and system improves the problems of relative independence of forward error correction channel coding (FEC) and high order modulation function modules, long code length dependence of FEC, limited spectral efficiency promotion under the limitation of fiber nonlinear effect, and high FEC decoding latency and power consumption in optical communication system. It is beneficial to improving the spectral efficiency and capacity of a coherent optical communication system and optimizing the system latency and power consumption.

Abstract: A communication receiver receives a signal sample stream of an orthogonal frequency division multiplexing (OFDM) signal, splits the signal sample stream into blocks, where each block corresponds to a symbol or a gap of the OFDM signal, determines an estimate of a periodic noise in the OFDM signal by averaging signal samples over a number of blocks, generates a noise-suppressed signal by subtracting the estimate of the periodic noise from the signal sample stream, and performs further receiver-side processing on the noise-suppressed signal.