Acousto-optic ambiguity function processor

The paper describes the design, construction and performance of a fully engineered and self-contained optical cross-ambiguity function processor. A matched pair of tellurium dioxide shear-mode acousto-optical cells are used to convert the two complex electrical input signals into a two-dimensional spatial modulation pattern on a light beam, which is then transformed optically into a light pattern representing the cross-ambiguity function for the two signals. A third acousto-optic cell controls light throughput, and the output pattern is recorded by a planar CCD photodetector array. By slightly reconfiguring the optics, the processor may also be operated as a triple product time-integrating correlator. A brief description is given of the mode of operation of the acousto-optic cells. Details of the design and construction of the processor are covered in some depth. The principal performance parameters of the processor are presented, together with photographs of the output patterns obtained for various input test waveforms. Finally, the processor is assessed in terms of its suitability for use as a range-velocity indicator in a pulse compression radar system.