Abstract

Photorefractive time-integrating correlator using BSO¹ and BaTiO₃² have been demonstrated previously. They have potential uses in radar pulse compression and adaptive processors for separating a narrowband noise such as a jamming signal from a broad-band signal such as a chirp radar signal or a phase-coded communication signal. However, in practice, a faster photorefractive medium is needed. In this paper, we investigate the feasibility of such an implementation using undoped photorefractive GaAs. In particular, the dynamic range, the bandwidth, and the response time of the system are investigated in detail. Both the old¹ and the new² configurations are considered. In addition, we observed in the output a fringe pattern with a spacing only a function of the bandwidth (chirp frequency range). This rules out the possibility that it is part of the correlation pattern. This fringe pattern exists in both the old and the new configurations. However, their fringe spacings are differed by a geometrical factor. The exact expressions for the fringe spacings in the old and the new configurations, respectively, are derived. They agree quite well with the experimental data.

© 1991 Optical Society of America