Accession Number : ADD011788

Title :   Sample Data Phase Locked Loop for Adaptive Doppler Tracker.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Roeder,A W

Report Date : 23 Apr 1985

Pagination or Media Count : 9

Abstract : Precise phase acquisition and tracking of a data modulated pulse signal in order to recover the data in a low signal to noise ratio environment is achieved by a sample data phase locked loop that is adaptive, second order, and uses baseband polar coordinate processing. The circuit utilizes an adaptive second order loop where the loop bandwidth can be adjusted by a coherence measurement. This provides wide bandwidths during initial acquisition, medium bandwidths during acquisition/track transition and narrow bandwidth during tracking.

Descriptors :   *PATENTS, *DOPPLER SYSTEMS, *ADAPTIVE SYSTEMS, *TRACKING, *PHASE LOCKED SYSTEMS, SAMPLING, LOOPS, BANDWIDTH, MODULATION, SIGNAL TO NOISE RATIO, COMMUNICATION AND RADIO SYSTEMS, PULSES, NARROWBAND

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE