Enhanced-resolution phased array radar

• US 8,736,484 B2
• Filed: 08/11/2010
• Issued: 05/27/2014
• Est. Priority Date: 08/11/2010
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Yu, Kai-Bor, Fernandez, Manuel F., Bachmann, Svetlana M.
• Primary Examiner(s): BYTHROW, PETER M
• Application Number:
  US12/854,473
• Publication Number:
  US 20120038504A1
• Time in Patent Office: 1,385 Days
• Field of Search: 342 13- 19, 342/81, 342/195, 342/26.R, 342/26.A, 342/26.B, 342/26.C, 342/26.D, 342 70- 74, 342146-158
• US Class Current: 342/81
• CPC Class Codes: G01S 2013/0254 Active array antenna
• CPC Class Codes: G01S 3/74 Multi-channel systems specially adapted for direction-finding, i.e. having a single antenna system capable of giving simultaneous indications of the directions of different signals systems in which the directions of different signals are determined sequentially and displayed simultaneously G01S3/04, G01S3/14
• CPC Class Codes: H01Q 21/061 Two dimensional planar arrays

Abstract

A system and method for increasing the effective angular resolution of a multi-function phased array radar system is provided. The system is operative to simultaneously transmit a plurality of overlapping sub-beams covering a representative central beam. A de-convolution process is applied to received return signals. The process includes determining the reflectivity within sub-beamwidth resolution cells defined by the overlapping sub-beams. Generated sub-beamwidth data provides the radar system with an effective angular resolution beyond that of any single transmitted beam.

Claims

1. A phased array radar system comprising:

an antenna array;

a transceiver operatively connected to the array, the transceiver configured to simultaneously transmit a center beam and a plurality of at least partially overlapping sub-beams covering the center beam, and receive respective return signals from each of the sub-beams; and

a processing module for processing received return signals from each of the sub-beams;

wherein the processing module is operative to generate resolution data corresponding to the overlapping portions of the transmitted sub-beams.

2. The system of claim 1, wherein the processing module performs a de-convolution operation, wherein the resolution data corresponding to the overlapping portions of the transmitted sub-beams is generated by applying a weighting matrix to the received return signals.

3. The system of claim 2, wherein the weighting matrix is derived from a matrix representative of the antenna pattern of the antenna array.

4. The system of claim 1, further comprising a control processor operatively connected to the transceiver, the control processor capable of operating the antenna array in multiple modes.

5. The system of claim 1, wherein the antenna array comprises a multi-function, phased array antenna.

6. The system of claim 1, wherein the center beam comprises a resolution cell, the resolution cell defining the minimum area in which two targets can be individually distinguished.

7. The system of claim 6, wherein the partial overlap of the sub-beams forms a plurality of sub-resolution cells within the resolution cell of the center beam.

8. A phased array radar system comprising:

an antenna array;

a transceiver operatively connected to the array, the transceiver configured to simultaneously transmit a center beam and a plurality of at least partially overlapping sub-beams covering the center beam, and receive respective return signals from each of the sub-beams; and

a processing module for processing received return signals from each of the sub-beams;

wherein the center beam comprises a resolution cell, the resolution cell defining the minimum area in which two targets can be individually distinguished;

wherein the partial overlap of the sub-beams forms a plurality of sub-resolution cells within the resolution cell of the center beam; and

wherein the processing module is operative to generate resolution data for each of the sub-resolution cells.

9. A method of operating a phased array radar system, the method comprising the steps:

transmitting a central beam and a plurality of overlapping sub-beams covering the central beam;

receiving return signals from the central beam and the overlapping sub-beams; and

generating, in at least one processor responsive to the received return signals, resolution data corresponding to the overlapping portions of the sub-beams.

10. The method of claim 9, wherein the step of generating resolution data includes applying a weighted matrix representative of the antenna pattern to the received return signals.

11. The method of claim 9, further comprising the step of forming a plurality of sub-resolution cells within a resolution cell defined by the central beam.

12. The method of claim 11, wherein the step of generating resolution data corresponding to the overlapping portions of the sub-beams comprises generating resolution data for each of the sub-resolution cells.