Accession Number : ADD012763
Title : Signal Analysis Receiver with Acousto-Optic Delay Lines.
Descriptive Note : Patent,
Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC
Personal Author(s) : Tsui,James B ; Davis,Robert L
Report Date : 17 Feb 1987
Pagination or Media Count : 6
Abstract : The system makes use of an interferometric Bragg cell for the time delays needed by the multiple antenna inputs in an angle-of-arrival (AOA) measurement system, for accurate measurements over wide bandwidths. A signal Bragg cell is modulated with a selected band of the EW signal environment, using a separate transducer coupled to each quadrant antenna element. A reference Bragg cell is modulated with a chirp signal. Coherent light from a laser is split and directed to both the signal cell and the reference cell. The output light beams from the reference Bragg cell and signal Bragg cell are combined and focused onto photo detectors having a one-dimensional array for each quadrant antenna element. The reference and signals are heterodyned at the photo detectors, which results in a channelized spectral output with each channel at the same intermediate frequency (IF). The outputs of the photodetectors are used by a phase comparison unit, cued by a frequency measurement receiver to the correct detectors, to provide the AOA measurement.
Descriptors : *PATENTS, *OPTICAL DETECTORS, *ACOUSTOOPTICS, *DELAY LINES, CHIRP RADAR, RADAR SIGNALS, ANGLE OF ARRIVAL, ANTENNA COMPONENTS, ANTENNAS, ARRAYS, BANDWIDTH, BRAGG ANGLE, CELLS, CHANNELS, COHERENT OPTICAL RADIATION, COMPARISON, DELAY, DETECTORS, FREQUENCY, INTERFEROMETRY, INTERMEDIATE FREQUENCIES, LASERS, ONE DIMENSIONAL, OUTPUT, PHOTODETECTORS, QUADRANTS, RECEIVERS, SIGNALS, SPECTRA, TIME INTERVALS, TRANSDUCERS
Subject Categories : Acoustooptic and Optoacoustic Devices
Optical Detection and Detectors
Distribution Statement : APPROVED FOR PUBLIC RELEASE