Jitter in nonlinearly coupled ring oscillators

The paper demonstrates possible (and useful) influence of nonlinear couplings between digital ring oscillators upon random instability (jitter) of the output waveforms. Symbolic analysis, based on simplified oscillator models, will show that the jitter can be reduced or enlarged, w.r.t. that of a single ring oscillator. Stochastic numerical simulation of circuit-level oscillator models will extend the symbolic analysis - so as to give more realistic bounds of range of jitter control and statistical properties of the jitter. It is hoped that the proposed coupled ring oscillators (with enlarged jitter) can become useful sources of uncertainty for True Random Number Generators (TRNGs).