Analysis of injection-locked pulsed waveform oscillators

Abstract

The injection-locked behaviour of a high efficiency pulsed waveform oscillator is analyzed in detail. The design is based on a closed-loop configuration, loaded with a short nonlinear transmission line (NLTL). A new technique is provided to predict the effect of the circuit elements on the synchronization bandwidth, which enables an overall optimization of the oscillator design, considering efficiency, pulse width and locking interval. The phase-noise minimum in free-running conditions, obtained for particular values of the design parameters, is investigated through the use of phase sensitivity functions. The impact of this minimum on the noise spectrum in injection-locked conditions is also studied. The techniques have been applied to a pulsed-waveform oscillator at 0.9 GHz.