Accession Number : ADD007036

Title :   Long Time Constant Clutter Tracker for Radar System.

Descriptive Note : Patent Application,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Cole,Lanier G

Report Date : 28 Jan 1980

Pagination or Media Count : 14

Abstract : A long time constant clutter track loop is used to correct velocity inputs to a high PRF radar and to correct for drift in the local oscillator thereby minimizing the effect of spurious signals and sidelobe clutter on the tracker error. A predicted clutter frequency signal is generated from the radar inertial navigation system and mixed with the main beam clutter doppler frequency signal. Any resulting error signals (the difference between the predicted clutter signal frequency and the actual received doppler clutter frequency signal) are detected and averaged in antenna scan quadrants over each 360 deg antenna scan. Components of velocity error from adjacent quadrants are used to adjust clutter velocity of the predicted clutter frequency signal for the next antenna scan period and the average error for all quadrants during a scan period provides DC offset for local oscillator drift. This is a continuation-in-part of co-pending patent application Serial No. 887,910 entitled LONG TIME CONSTANT CLUTTER TRACKER for RADAR STSTEM filed by Lanier C. Cole et al, 17 March 1978. (Author)

Descriptors :   *Patent applications, *Radar tracking, Radar clutter, Doppler radar

Subject Categories : Active & Passive Radar Detection & Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE