Multichannel acousto-optic correlator for time delay computation

Abstract

We built and experimentally tested an in-line interferometric time integrating correlator. This design demonstrates performance improvements compared to other time integrating correlators, because the +1 diffracted orders, which carry the information to be correlated, travel over a common path and because the undiffracted light from the first acousto-optic (AO) cell is used as the input to the second AO cell. The architecture also provides control of the conelation spatial frequency to match the detector elements spatial frequency. The simplicity of the design, improved light efficiency, and increased optical stability make it an attractive alternative for applications in radar signal processing and spectrum analysis.