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:
Nov. 16, 1999
Filed:
Apr. 06, 1998
Leslie A Priebe, Plano, TX (US);
Jerry D Holmes, Plano, TX (US);
Raytheon Company, Lexington, MA (US);
Abstract
A system and method for estimating azimuth angle, elevation angle and signal detection and which includes an antenna system having a plurality of elements, each element receiving a different concurrent portion of an incoming analog signal having a real and an imaginary portion. A converter is provided for each antenna element for converting each analog signal to digital form. A processor is provide for multiplying the sum of the real parts of the signals from a first group of the elements with the conjugate of the sum of the remainder of the elements to provided an estimated azimuth, elevation of signal detection measurement. In the case of a four element antenna, AzEst=Angle((A+B)*(C+D)Conjugate))=(x.sub.A +iy.sub.A +x.sub.B +iy.sub.B)*(x.sub.C -iy.sub.C +x.sub.D -iy.sub.D), ElEst=Angle((A+D)*(B+C)Conjugate))=(x.sub.A +iy.sub.A +x.sub.D +iy.sub.D)*(x.sub.B -iy.sub.B +x.sub.C -iy.sub.C) and Magnitude ((A+B*(C+D)Conjugate)) or Magnitude ((A+D*(B+C)Conjugate)). When the antenna system includes four antenna quadrants A, B, C and D, false detections due to responses coming from the sidelobe regions are suppressed by subtracting the offset OffsetAz=ScaleFactor*Magnitude(DeltaAz), where the offset is a scale factor to make the numbers come out correctly to provide a synthetic beam response: SyntheticAz=Magnitude((A+B)*(C+D)Conjugate)-OffsetAz the processor further including a comparator for comparing the Synthetic Az to a threshold to determine validity of the signal.