NLFM waveform generation using tunable integrated optical ring resonators: simulation and proof of concept experiment

The NLFM waveform resulting from a tunable integrated optical ring resonator is simulated. The metrics of interest are the first sidelobe levels and FWHM times of the autocorrelation, as these directly relate to the long-range performance and fine range resolution of a LADAR system, and should ideally be as small as possible. Through simulation, the maximum sidelobe level of the autocorrelation of an NLFM waveform generated by a series of tunable integrated optical ring resonators is shown to be -20 to -30 dB or lower. A proof of concept experiment employing an off-the-shelf thermally tunable silicon-nitride optical ring resonator is shown to generate NLFM chirped waveforms with a bandwidth of 28 kHz.