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A bstruet-A new acoustooptic architecture for performing real-time correlation of tigh-frequency wide-band signals has beerr developed. It uses a surface-acoustic-wave (SAW) delay line, and features the optical interference of two coherent light beams which have been Bra&-diffracted by SAW's propagating in the tine. The signal muttipiication, and subsequent time integration of the product formed, is performed by a photodiode array which deteets the diffracted tight. This arehitectrrre has achieved tirstebandwidths products exceeding 106 (34 MHz X 30 ins), and has several attributes which make it particularly well suited for use as a spread-spectrum signal processor. These include linearity of operation, large dynamic range, a large time aperture over which the correlation can be observed, and the ability to determine the center frequency and bandwidth of the signals. A correlator with this architecture has been used to detect a number of wide-band spread-spectrum signals. Its suitability for nse as a signal processor in several spread-spectrum systems is considered. I. INTRODUCTION EVERAL present-day radio systems munications, navigation, and radar used for commake use of spread-spectrum techniques to obtain greater range, multi-Manuscript