Performance Evaluation of APK Modulation for Nonlinear Satellite Communication Channel

Abstract

There is interest in getting high bit rate over satellite channel containing a nonlinear power amplifier. This paper studies different orders of amplitude phase shift keying (APK) modulation, 16-ary quadrature amplitude modulation (QAM) and predistortion considerations over the satellite power amplifier. Satellite transmission channel has been modelled to simulate and compare between methods for a better performance. The Saleh Model and Ghobni model has been selected from literature measurements of the travelling-wave tube-amplifier (TWTA) and solid state-power-amplifier (SSPA) respectively; however, in the simulation the TWTA gives better performance than SSPA in most modulation techniques. It was investigated with preditortion and without predistortion the best modulation constellation performance under nonlinear communication channel.Index Terms-Amplitude phase-shift keying (APK) modulation, nonlinear channel, and digital satellite communication.