Research of MAPSK modulation based on the nonlinear satellite channel

During the process of satellite data digital transmission, performance of the conventional Quadrature Amplitude Modulation (QAM) is degraded sharply because of nonlinear distortion resulting from High Power Amplifier (HPA). In this paper, M-ary Amplitude and Phase Shift Keying (APSK) modulation is proposed. According to the intra-ring distance and inter-ring distance, a function of the symbol error rate (SER) is presented and optimization of APSK signal constellations is studied. Finally, the optimal working point for APSK modulation under the condition of Saleh nonlinear model is found. Simulation shows that: at the same of SER, optimal MAPSK is superior to conventional MQAM over nonlinear satellite communication channels.