Voltage

Computer science

Optics

Antenna (radio)

Quantum mechanics

Photonics

Optoelectronics

Broadband

Telecommunications

Microwave

Band-pass filter

Ripple

Resonator

Phased array

Group delay and phase delay

Materials science

True time delay

Optical filter

Physics

Bandwidth (computing)

Optics Express

We present a novel broadband continuously tunable microwave photonic delay line consisting of a modulator, a four-stage microring resonator delay line, a tunable optical bandpass filter, and a photodetector. Unlike the traditional microring delay lines working at the on-resonant wavelength, the microring resonators in our chip work at the anti-resonant wavelengths, leading to a large delay bandwidth and a small delay ripple. The experimental results show that relative group delay can be continuously tuned from 0 to 160 ps for microwave frequencies in the range of 0 to 16 GHz. The delay ripple is less than 6.2 ps. These results represent an important step towards the realization of integrated continuously tunable delay lines demanded in broadband microwave phased array antennas.

Broadband continuously tunable microwave photonic delay line based on cascaded silicon microrings