N×N cyclic AWG with low and uniform insertion losses achieved by introducing array of tapered waveguides

This paper presents the design and simulation of N×N cyclic Arrayed Waveguide Grating (AWG) device in order to achieve the low and uniform insertion losses. There are two main purposes of this paper. The first purpose is to balance the insertion losses for all input ports by increasing the range of free spectral by three times. Using this method, consequently, the insertion losses for all input ports are uniformed. The root mean square (RMS) of the insertion loss, however, is significantly increased from 1.63 to 2.19 dB. The second purpose is to maintain the rise in the insertion loss. The tapers are therefore introduced to three different parts of AWG: input waveguides, and between input/output waveguides of an arrayed waveguide and free propagation regions (FPRs). It is found that the tapers help to reduced the average insertion loss dramatically to 1.14 dB, whereas the insertion losses for all input ports are still uniform.