Abstract: Due to the characteristics of long communication distance, large coverage area, and flexibility, satellite communications are widely used in earthquake rescue, radio and television and mobile communications. Satellite communication has problems such as long communication distance and environmental blocking to signals, which lead to a decline in communication quality. In order to improve the quality of satellite communication, we can increase the transmit power of the ground station or use diversity technology. Since electromagnetic waves have polarization characteristics, left-hand circularly polarized electromagnetic waves are orthogonal to right-handed circularly polarized electromagnetic waves, and the orthogonality can be used to realize independent transmission paths in long-distance communication. This paper mainly studies the related content of dual circular polarization diversity 2×2 MIMO, studies the channel parameters of open environment and urban environment, establishes a narrowband satellite dual circular polarization satellite 2×2 MIMO channel model, and designs a set of satellite 2×2 MIMO channel.The dual circular polarization satellite and personal mobile terminal transceiver system is simulated, and the SNR improvement of dual circular polarization diversity 2×2 MIMO is verified on the system compared with SISO.