True Time Delay Photonic Circuit Based on Perfluorpolymer Waveguides

A high-performance 4-bit optical true time delay device is realized on a perfluoropolymer integrated optic platform. The integrated waveguide circuit is based on athermal arrayed wavegide grating with monolithically integrated delay lines in a wavelength-selective recirculating loop configuration. The device provides precise delay length control (i.e., 1 m) over 16 channels with 40-ps incremental time delays. The device offers athermal operation over the 0°C-50°C range with a maximum insertion loss of 6.8 dB and a polarization shift of 0.4 nm. This compact device (20 × 32 × 3 mm³) promises applications in code-division multiple access and phased arrayed antenna systems, where the large channel counts with high resolution delay length controls and small footprints are required.