Underwater wireless optical communication system based on partial response shaping technology and TCM technology

Abstract

The invention relates to the field of underwater wireless optical communication, and discloses an underwater wireless optical communication system based on a partial response shaping technology and a TCM technology, which comprises an optical transmitting module, an optical receiving module, a transmitting end signal processing module and a receiving end signal processing module. The optical transmitting module converts the digital signal into an optical signal and then sends the optical signal to the optical receiving module, and the optical receiving module converts the optical signal into the digital signal. The transmitting end signal processing module carries out TCM coding, random interleaving, precoding, up-sampling and root raised cosine filtering on original data, and the receiving end signal processing module carries out resampling, root raised cosine filtering, synchronization, channel estimation, channel equalization, partial response shaping, de-interleaving and maximum likelihood sequence estimation on digital signals to obtain the original data. Compared with a traditional method, a partial response filter is added after full response channel equalization, noise amplification of a high-frequency part can be effectively restrained, the signal-to-noise ratio is increased, the bit error rate is reduced, and performance improvement is verified through simulation and experiments.

Description

technical field [0001] The invention relates to the field of underwater wireless optical communication, in particular to an underwater wireless optical communication system combining partial response shaping technology and TCM technology. Background technique [0002] With the gradual scarcity of land resources, the development and utilization of abundant marine resources has become an important development direction for all countries. Establishing a complete underwater communication network is of great significance for underwater exploration. Among them, the data and video transmission between underwater vehicles, underwater robots and underwater sensor nodes is an important problem that needs to be solved urgently. [0003] Wired communication has strong reliability and high communication rate. However, due to the immature development of domestic wet plug connectors, the use of wired communication will greatly increase the cost of equipment. Traditional underwater wireles...

AI Technical Summary

Problems solved by technology

The low bandwidth limitations brought by high-power lasers and high-sensitivity detectors introduce serious intersymbol interference (ISI), and existing channel equalization techniques such as least squares (LS), least mean squares (LMS) and frequency domain equalization The full-response equalizer used in the algorithm (FDE), etc., will amplify the noise while compensating the signal in the frequency band with severe fading, which will bring about a decrease in the signal-to-noise ratio (SNR). A partial-response equalizer is added after the full-response equalizer Shaping the signal spectrum can effectively suppress noise amplification, and the signal after partial response shaping is decoded by a Viterbi decoder

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