Abstract
We report a broadband radio frequency (RF) channelizer with up to 92
channels using a coherent microcomb source. A soliton crystal microcomb,
generated by a 49 GHz micro-ring resonator (MRR), is used as a
multi-wavelength source. Due to its ultra-low comb spacing, up to 92
wavelengths are available in the C band, yielding a broad operation
bandwidth. Another high-Q MRR is employed as a passive optical periodic
filter to slice the RF spectrum with a high resolution of 121.4 MHz. We
experimentally achieve an instantaneous RF operation bandwidth of 8.08
GHz and verify RF channelization up to 17.55 GHz via thermal tuning. Our
approach is a significant step towards the monolithically integrated
photonic RF receivers with reduced complexity, size, and unprecedented
performance, which is important for wide RF applications ranging from
broadband analog signal processing to digital-compatible signal
detection.