Hybrid Photonic True-Time Delay Modules for Quasi-Continuous Steering of 2-D Phased-Array Antennas

Hybrid photonic true-time delay modules for phased-array antennas are designed and demonstrated. Continuously tunable true-time delay network based on highly dispersive photonic bandgap fiber (up to 2135 ps/nm/km at 1570 nm), combined with a programmable true-time delay network utilizing optical waveguide delay line and optical switches, provides the antenna with quasi-continuous steering ability. Far-field patterns are simulated and measured to confirm the squint-free beam steering.