Arrayed-waveguide grating multiplexer with flat spectral response.

The design principle of a single-mode arrayed-waveguide grating multiplexer with flat spectral response is proposed on the basis of a discrete Fourier transform. By a beam propagation-method simulation, a flat spectral region (within 1-dB loss increase) is obtained over 57.2 GHz for 100-GHz channel spacing.