Antenna calibration

• US 8,004,457 B2
• Filed: 08/08/2008
• Issued: 08/23/2011
• Est. Priority Date: 08/31/2007
• Status: Expired due to Fees

• Current Assignee: BAE Systems Plc
• Original Assignee: BAE Systems Plc
• Inventors: Scott, Michael Andrew
• Primary Examiner(s): Tarcza; Thomas H
• Assistant Examiner(s): BYTHROW, PETER M
• Application Number:
  US12/302,148
• Publication Number:
  US 20100253570A1
• Time in Patent Office: 1,110 Days
• Field of Search: 342/165, 342/173, 342/174
• US Class Current: 342/174
• CPC Class Codes: H01Q 3/267 Phased-array testing or checking devices

Abstract

The present invention relates to antenna calibration for active phased array antennas. Specifically, the present invention relates to a built in apparatus for autonomous antenna calibration

Accordingly, the present invention provides a method of continuous on-line monitoring of each element in an array antenna comprising the steps of: (i) transmitting known test signals to one or more elements of the array antenna; (ii) monitoring responses of the elements to the test signals; and (iii)comparing the response with expected responses for the elements to determine an operation condition of the elements.

Claims

1. A method of continuous on-line monitoring of each element in an array antenna comprising a plurality of antenna elements forming an array face, the method comprising the steps of:

(i) mounting a plurality of calibration antennas around the periphery of the array face at a plurality of spaced locations from an edge of the array face;

(ii) transmitting known test signals from each of the calibration antennas in turn to one or more elements of the array antenna;

(iii) monitoring responses of the elements to the test signals; and

(iv) comparing the response with expected responses for the elements to determine an operation condition of the elements.

2. A method of continuous on-line monitoring according to claim 1, wherein the calibration antennas are mounted such that the elements are illuminated at high angles of incidence.

3. A method of continuous on-line monitoring according to claim 1, wherein the test signals are interspersed during normal operation of the array antenna.

4. A method of continuous on-line monitoring according to claim 2, wherein the test signals are interspersed during normal operation of the array antenna.