The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 25, 1997
Filed:
Dec. 07, 1995
Walter S Justice, Lexington, MA (US);
David A Marquis, Medford, MA (US);
Ronald A Wagner, Chelmsford, MA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A radar system having a transmitter for transmitting a series of radio frequency (RF) pulses with sequential, incrementally changing carrier frequencies. A receiver receives energy from multiple scattering points of an object reflecting such transmitted RF pulses. The received energy from each one of such scattering points includes a series of radio frequency (RF) pulses corresponding to the transmitted pulses delayed in time, .tau., from the transmitted pulses an amount proportional to the range to such scattering point and shifted in frequency from the carrier frequency an amount proportional to the velocity of such scattering point. The receiver includes a heterodyning section, responsive to a range tracking error signal, .epsilon..sub.R, and a velocity tracking error signal, .DELTA..sub.VEL, for producing a series of pulsed signals for each one of the scattering points. Each one of the pulsed signals for any given scatterer sequentially changes in phase, .phi., at a rate, .DELTA..phi./.DELTA.T, related to the range to the scattering point producing such one of the pulsed signal series. A processor, responsive to each of the series of pulsed signals produced by the heterodyning section, unambiguously determines from the frequency spectrum thereof the range tracking error signal, .epsilon..sub.R, and velocity tracking error signal, .DELTA..sub.VEL, for each of the scattering points as well as the range centroid.