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A method for determining beamformer scattering parameters for a plurality of phased array radar antenna subarrays that each include a radiating (e.g., dipole) component and a beamformer component provides for obtaining for the plurality of phased array radar antenna subarrays a plurality of electrom

A method for determining beamformer scattering parameters for a plurality of phased array radar antenna subarrays that each include a radiating (e.g., dipole) component and a beamformer component provides for obtaining for the plurality of phased array radar antenna subarrays a plurality of electromagnetic measurements at a plurality of ports. Analogous electromagnetic measurements are obtained for a reference subarray including a radiating component but absent a beamformer component. The plurality of phased array radar antenna subarray electromagnetic measurements and the reference subarray electromagnetic measurements provide a plurality of beamformer scattering parameter values for the plurality of phased array radar antenna subarrays that may be used in modeling and calibrating a phased array radar apparatus that may be assembled from the plurality of phased array radar antenna subarrays.

대표청구항 ▼

1. A method for determining scattering parameters for an operational phased array radar antenna subarray, the method comprising the steps of: measuring, using a reference subarray that includes a dipole component but not a beamformer component, values for a plurality of reference electromagnetic par

1. A method for determining scattering parameters for an operational phased array radar antenna subarray, the method comprising the steps of: measuring, using a reference subarray that includes a dipole component but not a beamformer component, values for a plurality of reference electromagnetic parameters;measuring, using an operational phased array radar antenna subarray that includes the dipole component and the beamformer component, values for a plurality of operational electromagnetic parameters; andcalculating from the values for the plurality of operational electromagnetic parameters and the values for the plurality of reference electromagnetic parameters beamformer scattering parameters for the operational phased array radar antenna subarray. 2. The method of claim 1 wherein the plurality of reference electromagnetic parameters includes reference port parameter signals. 3. The method of claim 1 wherein the plurality of operational electromagnetic parameters includes operational port parameter signals. 4. The method of claim 1 wherein the measuring the values for the plurality of reference electromagnetic parameters and the measuring the values for the plurality of operational electromagnetic parameters is undertaken in an electrical test apparatus that electromagnetically energizes one test port and measures a signal at the remaining test ports. 5. The method of claim 1 wherein the calculating uses the equation: Bcd=Tca(Taa−Saa+SadS−1ddSda)−1SadS−1dd where:B, S and T denote scattering parameter row (Bcd, Tca) and square (Saa, Taa, Sad, Sdd, Sda) matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 6. The method of claim 1 wherein the calculating uses the equation: Bdd=[Sda(Taa−Saa)−1Sad+Sdd]1 where:B, S and T denote scattering parameter square matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 7. The method of claim 1 wherein the calculating uses the equation: Bdd=[Sad+(Taa−Saa)S−1daSdd]−1(Taa−Saa)S−1da where: B, S and T denote scattering parameter square matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 8. A method for calibrating a phased array radar, the method comprising the steps: measuring, using a reference subarray that includes a dipole component but not a beamformer component reference array port, parameter signals for the reference subarray;measuring, for each of a plurality of operational phased array radar antenna subarrays each of which include the dipole component and the beamformer component, a corresponding plurality of operational array port parameter signals for the plurality of operational phased array radar antenna subarrays;calculating for the plurality of operational phased array radar antenna subarrays a corresponding plurality of calculated beamformer parameters from the reference array port parameter signals and the plurality of operational phased array antenna subarray port parameter signals; andusing the plurality of calculated beamformer parameter values for the plurality of operational phased array radar antenna subarrays in a general electromagnetic analysis model to determine modeled radar performance characteristics for a phased array radar comprising the plurality of operational phased array radar antenna subarrays. 9. The method of claim 8 further comprising correlating the modeled radar performance characteristics with a look-up table to calibrate the phased array radar. 10. The method of claim 8 wherein the calculated beamformer parameters comprise beamformer scattering parameters for the plurality of operational phased array radar antenna subarrays. 11. The method of claim 8 wherein the general electromagnetic model uses a computational electromagnetic analysis computer code. 12. The method of claim 8 wherein the calculating uses the equation: Bcd=Tca(Taa−Saa+SadS−1ddSda)−1SadS−1dd where:B, S and T denote scattering parameter row (Bcd, Tca) and square (Saa, Taa, Sad, Sdd, Sda) matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 13. The method of claim 8 wherein the calculating uses the equation: Bdd=[Sda(Taa−Saa)−1Sad+Sdd]−1 where:B, S and T denote scattering parameter square matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 14. The method of claim 8 wherein the calculating uses the equation: Bdd=[Sad+(Taa−Saa)S−1daSdd]−1(Taa−Saa)S−1da where: B, S and T denote scattering parameter square matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 15. A test apparatus comprising: an array of test ports that terminate with an array of test dipoles that mate with an array of dipoles on a phased array radar antenna subarray; andmeans for energizing one of the test ports with an external signal while measuring a response to the external signal at the remainder of the test ports. 16. The test apparatus of claim 15 wherein the phased array radar antenna subarray is separate from a phased array radar apparatus. 17. A test system comprising: a test apparatus comprising: an array of test ports that terminate with an array of test dipoles that mate with an array of dipoles on a phased array radar antenna subarray; andmeans for energizing one of the array of test ports with an external signal while measuring a response to the external signal at the remainder of the test ports; anda computer programmed for calculating values for beamformer scattering parameters from the external signal and the response to the external signal. 18. The test system of claim 17 wherein the calculating uses the equation: Bcd=Tca(Taa−Saa+SadS−1ddSda)−1SadS−1dd where:B, S and T denote scattering parameter row (Bcd, Tca) and square (Saa, Taa, Sad, Sdd, Sda) matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 19. The test system of claim 17 wherein the calculating uses the equation: Bdd=[Sda(Taa−Saa)−1Sad+Sdd]−1 where:B, S and T denote scattering parameter square matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port. 20. The test system of claim 17 wherein the calculating uses the equation: Bdd=[Sad+(Taa−Saa)S−1daSdd]−1(Taa−Saa)S−1da where:B, S and T denote scattering parameter square matrices with identical normalizing impedances; andsubscripts xy, where x and y are independently a, c and d, are reflected signal at the x port with respect to incident signal at the y port.