Accession Number : ADA261983


Title :   Modified Acousto-Optic Adaptive Processor (Mod-AOAP)


Descriptive Note : Final rept. Feb 1989-Jun 1992


Corporate Author : ROME LAB ROME NY


Personal Author(s) : Keefer, Christopher W ; Malowicki, John E ; Payson, Paul M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a261983.pdf


Report Date : Dec 1992


Pagination or Media Count : 35


Abstract : Multipath jamming noise introduced into a radar antenna's sidelobes effectively reduces the radar's target detection capability. The acousto-optic adaptive processor (AOAP) was developed to demonstrate an optical implementation of the least mean square (LMS) algorithm for adaptively cancelling noise jamming. The AOAP system demonstrated 30 dB cancellation of monotone CW signals, with degraded performance as the bandwidth increased. The liquid crystal light valve (LCLV), used as the integrator/ spatial light modulator in the AOAP, has been identified as limiting system performance. In this report we report on modifications to the AOAP. Specifically, the LCLV has been replaced with a photorefractive crystal. Cancellation performance and cancellation speed of the mod-AOAP are presented and compared to the original results.


Descriptors :   *SIGNAL PROCESSING , *RADAR JAMMING , *NOISE JAMMING , *ACOUSTOOPTICS , ELECTROOPTICS , RADAR , RADAR COUNTERMEASURES , LASER BEAMS , LIQUID CRYSTALS , BANDWIDTH , ELECTRONIC COUNTERMEASURES , LIGHT MODULATORS , NOISE JAMMERS , COUNTER COUNTERMEASURES , SIDELOBES , MODULATORS , RADAR ANTENNAS , ECHOES , ADAPTIVE SYSTEMS , JAMMING , INTEGRATORS , RADAR SIGNALS , TARGET DETECTION


Subject Categories : Acoustooptic and Optoacoustic Devices
      Radar Countermeasures


Distribution Statement : APPROVED FOR PUBLIC RELEASE