Communications: directive radio wave systems and devices (e.g. – Return signal controls radar system – Receiver
Reexamination Certificate
2001-09-07
2003-11-25
Lobo, Ian J. (Department: 3662)
Communications: directive radio wave systems and devices (e.g.,
Return signal controls radar system
Receiver
C342S017000, C342S154000
Reexamination Certificate
active
06653973
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to radar systems generally, and more specifically to radar systems that determine direction of arrival of one or more targets in the presence of jamming.
BACKGROUND OF THE INVENTION
Modern radar's function, in addition to conventional target detection and tracking, involves target discrimination and kill assessment. Current radar systems cannot resolve multiple sources within a resolution cell. Modern signal processing techniques can determine the number of sources and resolve the associated azimuth and elevation angles beyond the Rayleigh resolution using model-based approach. This set of techniques is called super-resolution techniques. Super-resolution techniques are being investigated for insertion into emerging radar products.
Modern radars are vulnerable to diverse threats: intentional jamming, spoofing and radar frequency interference (RFI). Also, in air and missile defense applications, the target complex may include countermeasures such as jamming and chaff. There is no known method of maintaining super-resolution capabilities in the presence of jamming.
SUMMARY OF THE INVENTION
The present invention is a method and system for detecting one or more radar targets of interest in the presence of jamming signals. A plurality of sub-arrays are formed from an antenna array. Sub-array beams are adaptively formed so as to point one or more nulls in one or more respective directions corresponding to one or more jammers. A super-resolution technique is applied to determine a count of the one or more radar targets.
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Duane Morris LLP
Lobo Ian J.
Lockheed Martin Corporation
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