<title>Compact silicon-based integrated optical time-delay network</title>

Abstract

Conventional phased-array antennas are limited by the bandwidth and attenuation as well as mechanical rigidity of the coaxial cables employed to perform the microwave phase shift. Photonic technology offers advantages in distribution of the microwave signal including lightweight, compact delay lines, immunity from electromagnetic interference, low rf transmission loss and possibility of optical signal processing on the microwave encoded optical beam. Fiber optic delay lines have been demonstrated already but one requires a precision cut of the fiber length (accurate to a mm) to achieve accurate psec time delay. Guided-wave based approach allows precise definition of the waveguide delay line lengths. In addition, reproducible delays can be mass- produced ensuring low cost modules. In this paper, we demonstrate the first integrated optical delay lines in the silicon-on-insulator waveguide technology.