• PHASE AND FREQUENCY TRACKING CONSIDERATIONS FOR HETERODYNE OPTICAL COMMUNICATIONS

      Kaufmann, John E.; Massachusetts Institute of Technology (International Foundation for Telemetering, 1982-09)
      In heterodyne optical communications, phase or frequency tracking is generally needed to avoid performance degradation when signaling in the presence of laser frequency jitter and Doppler shifts. This paper examines a phase-lock loop approach for BPSK and two forms of frequency tracking for MFSK. Using a statistical model for laser frequency instability, the performance of these schemes is calculated by a linear analysis of the tracking loop in the small-error regime.