Dual-polarization Mode Microwave Channelizer with a Kerr Soliton Crystal
Microcomb
Abstract
We report a dual-polarization radio frequency (RF) channelizer based on
microcombs. With the tailored mismatch between the FSRs of the active
and passive MRRs, wideband RF spectra can be channelized into multiple
segments featuring digital-compatible bandwidths via the Vernier effect.
Due to the use of dual-polarization states, the number of channelized
spectral segments, and thus the RF instantaneous bandwidth (with a
certain spectral resolution), can be doubled. In our experiments, we
used 20 microcomb lines with ~ 49 GHz FSR to achieve 20
channels for each polarization, with high RF spectra slicing resolutions
at 144 MHz (TE) and 163 MHz (TM), respectively; achieving an
instantaneous RF operation bandwidth of 3.1 GHz (TE) and 2.2 GHz (TM).
Our approach paves the path towards monolithically integrated photonic
RF receivers (the key componentsâ\euro”active and passive MRRs are
all fabricated on the same platform) with reduced complexity, size, and
unprecedented performance, which is important for wide RF applications
with digital-compatible signal detection.