Application of Angular Method to Correct Channel Spacing Between AWG Demultiplexed Channels

D. Seyringer
Vorarlberg University of Applied Sciences,

Keywords: arrayed waveguide gratings, optical multiplexers/demultiplexers, AWG, channel spacing


Arrayed Waveguide Gratings (AWGs) offer an attractive DWDM solution because they are a very compact way to provide for higher channel count solutions, have good performance characteristics, and can be more cost effective per channel than other methods. AWG is designed to multiplex/demultiplex a particular number of wavelengths used as the transmitting channels; having a particular channel spacing, df between them. According to ITU-Grid this parameter is constant over all the transmitted channels in frequency domain i.e. it is not constant in the wavelength domain. This is due to the nonlinear dependency between the wavelength and frequency. However, the channel spacing between AWG transmitted optical signals is, in opposite to this, constant in wavelength domain but not in the frequency domain. To solve this problem, an angular method was developed and applied to 40-channel, 100 GHz AWG design and technologically verified. This method has no influence on AWG performance and can be used to correct the channel spacing of any AWG type.