Applications of Pulsed-Waveform Oscillators in Different Operation Regimes

In this paper, following previous works, a pulsed-waveform oscillator is made up of a feedback loop containing an amplifier stage and a nonlinear transmission line. Efficient simulation techniques are applied for the correction of waveform nonidealities. A global stability analysis of the pulsed-waveform oscillator is performed, considering two relevant circuit parameters. All the possible oscillation modes are taken into account in this analysis, with the aim to guarantee operation in the desired mode only. The jitter in the pulsed waveform is quantified with a phase-noise analysis, and the uncommon form of variation of the phase-noise spectral density is understood with the aid of a semianalytical formulation. The injection-locked operation of the pulsed-waveform oscillator is also investigated, examining its robustness and possible advantages and applications. In particular, we will consider the injection-locked mode at a subharmonic frequency and analyze the resulting phase-noise spectrum, which will be compared with that of the free-running pulsed-waveform oscillator. The application as a frequency multiplier will be considered. The techniques have been applied to a prototype at 1 GHz with very good agreement with the measurement results.