Satellite-borne coherent laser communication diversity system based on MIMO

Abstract

The invention discloses a satellite-borne coherent laser communication diversity system based on MIMO. The satellite-borne coherent laser communication diversity system comprises a transmitting end upper computer; an error correction encoder, the front end of the error correction encoder being connected with the transmitting end upper computer; a space-time encoder, the front end of the space-timeencoder being connected with the rear end of the error correction encoder; a phase modulator, the front end of the phase modulator being connected with the rear end of the space-time encoder; a laser; a telescope; an interference filter; a beam splitter; a channel estimator, used for receiving one path of incident light from the beam splitter; a combiner; a local oscillator laser; the front end of the demodulator is connected with the rear end of the photoelectric detector; a error correction decoder, the front end of the error correction decoder being connected with the rear end of the demodulator; and a receiving end upper computer, wherein the receiving end upper computer is connected with the rear end of the error correction encoder.

Description

technical field [0001] The invention relates to the technical field of satellite communication, in particular to a space-borne coherent laser communication diversity system based on MIMO. Background technique [0002] Coherent detection has advantages in receiving sensitivity. For the detection of weak signal strength such as space long-distance communication links, coherent detection has a greater improvement in communication rate and detection sensitivity than direct detection laser communication systems. In order to further improve the detection sensitivity, the diversity receiving technology is currently mainly used to use multiple optical antennas to receive optical signals at the receiving end. When the signals received by each branch are independent of each other, combining them properly can effectively improve the influence of the channel on the performance of the space communication system. . [0003] The traditional space-borne coherent laser communication diversi...

AI Technical Summary

Problems solved by technology

The traditional space-borne coherent laser communication diversity technology uses one transmission and multiple receptions to improve the receiving signal-to-noise ratio. In the space-borne laser communication scenario, the increase in the size and weight of the payload will increase the cost and difficulty of manufacturing the satellite.

For example, in the above example, the one-send-four-receive mode improves the receiving signal-to-noise ratio by four times compared with the one-send-one-receive mode, but the load carried by the satellite is also increased from one laser and one optical antenna to one laser and four Optical antennas increase the difficulty of satellite production Satellite cost and launch cost

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