Optical delay line employing an arrayed waveguide grating in fold-back configuration

A novel optical delay line (ODL) using an arrayed-waveguide grating (AWG) in fold-back configuration is proposed and experimentally demonstrated. This fold-back configuration offers crosstalk reduction and loss-imbalance as compared with previously reported loop-back AWG-based ODL. The experimental results show that different highly accurate delays can be obtained with a single AWG over a huge modulation bandwidth (2-18 GHz).