Optimally apodized ring-resonator filter for DPSK demodulation

Optical micro-ring resonator arrays (OMRA) are versatile elements for designing various photonic integrated circuits and systems for optical signal processing and communication. In this paper, we analyze the performance of an OMRA used for optical demodulation of both single channel DPSK and 3-channel WDM-DPSK signals. Several apodization profiles have been investigated to decide for the optimal performance. It is shown that OMRA with Tanh apodization profile results in an overall superior performance compared to other profiles considered based on same 3-dB bandwidth of the OMRA filter in each case of apodization.