Optical adaptive filtering for Doppler shift simulator

Based on free space laser communication, this article describes the working principle of electro-optical frequency shifting, designs an optical adaptive filtering module, and builds the core module of the dynamic optical Doppler shifting simulator for laser channel. It is expected to be applied to the heaven-ground integrated communication link. In this article, we adopt the electro-optical frequency shifting technique combined with the microwave-light wave. In the 1 550 nm band, the negative feedback algorithm is used to complete the adaptive filtering, which realizes optical Doppler frequency shifting and high-precision locking. The frequency shift range reaches +5.5-+32 GHz, and the analog precision is better than 645 Hz. When the microwave frequency is greater than 13.5 GHz, the signal-to-noise ratio(SNR) of the output optical power reaches 20 d B, which lays the foundation for the next stage space laser communication.