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OFDM and self-coherent detection based satellite-to-ground communication system

In this paper, we propose a scheme using Orthogonal Frequency Division Multiplexing (OFDM) and self-coherent detection to enhance satellite-to-ground data links, with improved communication data rate and detection performance. We analyzed this free space optical communication systems theoretically, with preliminary experimental results being demonstrated. In the experiment, quadrature phase shift keying and 16-quadrature amplitude modulation OFDM signals were transmitted and detected by coherent receiver respectively.