Design of cyclic arrayed waveguide grating with distributed waveguide directions for uniform loss

We propose a novel method to achieve cyclic arrayed waveguide grating (AWG) router with uniform channel insertion loss over the entire free spectral range (FSR). By appropriately distributing the pointing directions of the arrayed waveguides at the output star coupler to the entire output waveguide array instead of the central output alone in conventional design, the optical energy of different wavelengths can be uniformly distributed to different output waveguides. The simulation results show that such a design can substantially reduce the channel insertion loss nonuniformity from 3dB to less than 1 dB.