Design of a GaAs acousto-optic correlator for real-time processing

In this paper, the design and the simulation of a GaAs acousto-optic correlator for synthetic aperture radar (SAR) data processing are reported. The proposed integrated circuit is available for airborne applications and is able to operate with side-looking focused radar. The range compression is performed by the acousto-optic correlator, driven by the received signal, and the azimuth data compression is obtained by using a transmission mask/charge coupled device (CCD) system. Data for coherent compression are collected according to the pulse repetition frequency (PRF) of the reference chirp signal which modulates the laser beam. The proposed integrated circuit allows SAR signal processing on a substrate with very small sizes (37 X 17 mm2) and low power consumption. A range resolution of 126 cm and an azimuth resolution of 68 cm have been theoretically achieved.