Polarization division multiplexed photonic radio-frequency channelizer using an optical comb

A polarization division multiplexed photonic radio-frequency (RF) channelizer based on an optical comb is proposed and numerically investigated. A flat optical comb with nine lines is generated using two cascaded Mach–Zehnder modulators. The input broadband signal is simultaneously multicast by the optical comb and its frequency-shifted duplicate. These two combs are polarization multiplexed, spectrally sliced by a Fabry–Pérot etalon (FPE), polarization de multiplexed and then channelized by wavelength division multiplexers (WDMs). The key advantage of the proposed approach is that it releases the trade-off between the measurement range and accuracy of a conventional optical comb based channelizer by a factor of 2. The impact of the polarization misalignment, the capability of monitoring multi-frequency RF signals with different powers and the reconfigurability of the system are also evaluated.