Numerical evaluation of coherent signals for deep-space links

Abstract

We numerically evaluate the deep-space communication performance in a broadband lossy channel of coherent pulse position modulation (PPM) with on/off receiver. We also consider quadrature amplitude modulation (QAM) signal and phase-shift keying (PSK) signal with dyne-type detections. We find that for an extremely weak signal input power, multilevel PPM system is good strategy, while for an extremely strong signal, multilevel QAM system is recommended.