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:
Jul. 30, 1985
Filed:
Feb. 10, 1982
Ben H Cantrell, Springfield, VA (US);
William B Gordon, Rockville, MD (US);
Gerard V Trunk, Baltimore, MD (US);
Other;
Abstract
A method of estimating the angles of arrival .theta.1 and .theta.2 of two closely spaced radar targets of which one target may be the virtual image of the other target. The targets are illuminated with a radar beam of wavelength WL, and the resulting echos from the targets are received at three directive antennas whose apertures are coplanar and whose phase centers are colinear and spaced a distance D apart. The received echos are converted to complex numbers S1, S2 and S3 representing the magnitude and phase of the respective echos received by the three directive antennas. If the plane of symmetry of the two targets is known, the value of a parameter WD is determined which minimizes L=.vertline.S1-WB(WD+WD*)S2+WB.sup.2 S3.vertline..sup.2, where WB=exp (j2.pi.D.theta.B/WL) and .theta.B is the known angle bisecting the angles of arrival of the two targets. If the plane of symmetry of the two targets is not known, the values of WD and WB are determined by solving for WD and WB which minimize L. The final step, in each case, is calculating the angles of arrival .theta.1 and .theta.2 from .theta.1=(WL2.pi.D)tan.sup.-1 [Im(WD.multidot.WB)/Re(WD.multidot.WB)], and .theta.2=(WL/2.pi.D)tan.sup.-1 [Im(WD*.multidot.WB)/Re(WD*.multidot.WB)].