Phase and frequency tracking considerations for heterodyne optical communications
Abstract
Heterodyne optical communications systems represent a potential for substantial performance improvement over direct detection systems. Certain difficulties can arise, however, in heterodyne systems, in connection with a frequency instability of the employed laser. In general, frequency or phase tracking will be needed at the receiver to avoid significant degradations in communications performance and requirements for increased transmitter power unless very stable lasers are available. The present investigation is concerned with receiver phase and frequency tracking schemes suitable for heterodyne PSK and MFSK (multilevel frequency-shift-keying) systems in a space communications context, although this work is also applicable to fiberoptic systems.
- Publication:
-
ITC/USA/'82; Proceedings of the International Telemetering Conference
- Pub Date:
- 1982
- Bibcode:
- 1982isa..conf..123K
- Keywords:
-
- Frequency Shift Keying;
- Optical Communication;
- Optical Heterodyning;
- Phase Shift Keying;
- System Effectiveness;
- Tracking Problem;
- Doppler Effect;
- Feedback Control;
- Frequency Stability;
- Laser Stability;
- Phase Locked Systems;
- Transmission Efficiency;
- Communications and Radar