Accession Number : AD0164667
Title : Method and Means for Equalizing the Response of Signal Channels in a Multiple Channel Improved System.
Descriptive Note : Patent,
Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON D C
Personal Author(s) : Weir,Donald E.
Report Date : 05 MAR 1974
Pagination or Media Count : 8
Abstract : The patent relates to an automatic responsivity control in a multiple channel infrared system realized by means of reference signals derived from a modulated light source. The light source illuminates both the infrared element array and a separate reference signal detector. The infrared video signal and the reference signals transmitted in each infrared system channel are passed through a variable gain amplifier. The gain of the variable gain amplifier (and hence the magnitude of the reference signal) is controlled by a circuit including a synchronous filter, a synchronous detector, a DC reference voltage source, and a voltage controlled resistor. The separate reference signal detector provides drive signals to control the synchronous filter and also provides a 180 degrees phase shifted reference signal that is used to cancel the reference signal in the output of the variable gain amplifier.
Descriptors : *Infrared detectors, *Patents, Signal processing, Video signals, Response, Multiple operation, Automatic, Control
Subject Categories : Infrared Detection and Detectors
Distribution Statement : APPROVED FOR PUBLIC RELEASE