Space-Time-Frequency-Coding Joint Signal Processing for Satellite Constellation Communication System: A Simulation Study

Space-Time-Frequency-Coding (STFC) joint processing (or MIMO-OFDM system with channel coding) is an effective approach to improve the spectrum efficiency of wireless communications. In this paper, we study the feasibility of STFC scheme for satellite communication constellation system based on simulation experiments. In particular, we built a complete simulation platform based on the typical scenario of a satellite constellation system, and implemented the key modules for STFC, including 2-D pilot assisted channel estimation for the channel with space-ground Doppler shift and efficient STFC encoding and decoding. Different configurations are proposed by combining different modulation levels and different subcarrier spacing. Experiment results show that the STFC system can support a total throughput up to 10 Gbps for an orbit plane at Ka-band, but performance of STFC is not good at the boundary of the coverage of a ground station due to large Doppler shift. In addition, the system with larger subcarrier spacing is more robust to the Doppler shift than that with smaller subcarrier. These results verify the correctness and effectiveness of the established STFC simulation platform, and show the feasibility of the STFC scheme for the satellite constellation system.