Analysis and optimization for a polymer cross-grid array of microring resonant wavelength multiplexers

Based on formulas presented for the amplitude coupling ratio and the transfer function, transmission characteristics are analyzed and parameters are optimized for a polymer cross-grid array of microring resonant wavelength multiplexers around the central wavelength of 1.550918 μm with wavelength spacing 1.6 nm. In the design of the device, by means of selecting a resonant order m=95 and introducing a resonant order increment of adjacent filter elements Δm=2, we increase the ring radius difference of adjacent filter elements ΔR from 17 nm (for the case of Δm=0) to 337 nm. Calculated results show that the 3‐dB bandwidth is about 0.2 nm, the ratio between the −1- and −10‐dB bandwidths is about 0.22, the insertion loss is less than 0.5 dB, and crosstalk is below −39 dB for each of the eight horizontal output channels.