Phase Transients of Injection Locked Gunn Oscillators for Microwave Pulse Communication

Using specially selected phase-locking systems, the phase transients of Gunn oscillators have been studied with the help of Lissajous figures on a fast sampling oscilloscope. The results show that phase transients can exhibit a complex oscillatory behaviour which only reaches a steady state after a considerable time. Theoretical results based on a phase plane analysis for the dynamic behaviour of phase and amplitude transients for injection locking confirm these experimental observations. Criteria are presented regarding optimum conditions for fast phase switching as employed for such applications as phase-shift-keyed P.C.M. systems.