System and method for mitigating co-channel interference in passive coherent ...

(54) SYSTEM AND METHOD FOR MITIGATING CO-CHANNEL INTERFERENCE IN PASSIVE COHERENT LOCATION APPLICATIONS

(75) Inventor: Kevin W. Baugh, Gaithersburg, MD (US)

(73) Assignee: Lockheed Martin Corporation,

Gaithersburg, MD (US)

( * ) Notice: Subject to any disclaimer, the term ol this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.

(21) Appl. No.: 10/137,646

(22) Filed: May 3, 2002

(65) Prior Publication Data

US 2002/0167440 Al Nov. 14, 2002

Related U.S. Application Data

(60) Provisional application No. 60/288,448, filed on May 4, 2001, and provisional application No. 60/288,451, filed on May 4, 2001.

(51) Int. CI.7 G01S 13/87; G01S 31/02

(52) U.S. CI 342/125; 342/55; 342/453

(58) Field of Search 342/55, 125, 453,

342/463, 464

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Primary Examiner—Ian J. Lobo

(74) Attorney, Agent, or Firm—Hogan & Hartson L.L.P. (57) ABSTRACT

A system and method for mitigating co-channel interference is disclosed. A radar system detects targets from received signals at an antenna array. The received signals include direct signals and target signals transmitted from remote transmitters. An antenna array receives the signals. A signal processing system is coupled to the antenna array to perform processing operations on the received signals. The processing system includes a primary cancellation component and a secondary cancellation component. A primary illuminator signal is cancelled from the received signals by the primary cancellation component. An adaptive beam former obtains a secondary illuminator signal from the received signals. A reference regenerator regenerates the secondary illuminator signal. An adaptive cancellation filter removes noise from the secondary illuminator signal. The secondary cancellation component mitigates co-channel interference by canceling the secondary illuminator signal from the received signals.

32 Claims, 4 Drawing Sheets

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