Numerical investigation of a free-space optical coherent communication system based on optical phase-locked loop techniques for highspeed intersatellite data transmission

Abstract:
We present a numerical investigation of current high-speed optical intersatellite communication. The considered laser communication terminal (LCT) uses an optical phase-locked loop (OPLL) which ensures stable homodyne detection. The corresponding phase and frequency acquisition will be investigated in detail together with the main impairments like phase and shot noise. The phenomenon of cycle slips is statistically investigated as well as the impact of Doppler shift on the signal frequency due to the relative velocity between the satellites. Finally, a possible extension for the homodyne concept of QPSK modulation will be discussed which allows even higher data rates.