Method and apparatus for calibrating phased array receiving antennas
First Claim
1. A calibrator for calibrating phased array antennas which include a plurality of individual antenna receiving and delay elements, the calibrator comprising:
- calibration signal generating means for generating first and second separable calibration signals;
calibration cable means including a calibration signal cable having opposite ends connected to respective outputs of the calibration signal generating means for receiving respective ones of the first and second calibration signals;
calibration signal injecting means connecting the calibration signal cable to inputs of each of the antenna receiving elements;
power summing means coupled to outputs of the antenna delay elements;
delay measurement means coupled to the calibration signal generating means and to the power summing means for measuring calibration signal delays or phase shifts of the first and second calibration signals at outputs of each of the antenna delay elements; and
computer means coupled between the delay measurement means and the antenna delay elements for summing and averaging the measured signal delays or phase shifts in the first and second calibration signals, and for adjusting the signal delays or phase shifts of selected antenna delay elements in response thereto.
2 Assignments
0 Petitions
Accused Products
Abstract
Disclosed is a method and apparatus for calibrating phased array receiving antennas that includes circuitry for generating a pair of calibration signals separable one from the other. The signals are injected into the delay elements of the antenna from opposite ends of a complementary calibration cable. The delay produced in the calibration signals is individually measured, and the delays summed and averaged to produce a delay measurement independent of delays produced by the calibration cable and accordingly delay measurement variations caused by environmental effects on the calibration cable.
-
Citations
17 Claims
-
1. A calibrator for calibrating phased array antennas which include a plurality of individual antenna receiving and delay elements, the calibrator comprising:
-
calibration signal generating means for generating first and second separable calibration signals; calibration cable means including a calibration signal cable having opposite ends connected to respective outputs of the calibration signal generating means for receiving respective ones of the first and second calibration signals; calibration signal injecting means connecting the calibration signal cable to inputs of each of the antenna receiving elements; power summing means coupled to outputs of the antenna delay elements; delay measurement means coupled to the calibration signal generating means and to the power summing means for measuring calibration signal delays or phase shifts of the first and second calibration signals at outputs of each of the antenna delay elements; and computer means coupled between the delay measurement means and the antenna delay elements for summing and averaging the measured signal delays or phase shifts in the first and second calibration signals, and for adjusting the signal delays or phase shifts of selected antenna delay elements in response thereto. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A method for calibrating a phased array receiving antenna which includes an array of individual antenna receiving elements and delay elements, comprising the steps of:
-
injecting first and second separable calibration signals into each of the delay elements of the antenna through opposite ends of a complementary calibration cable connected to the inputs thereof; measuring the delay in the first calibration signal produced by a delay element k; measuring the delay in the second calibration signal produced by a delay element k; summing and averaging a delay in the first and second calibration signals to generate an average delay produced by the delay element independent of the delay produced therein by the calibration cable. - View Dependent Claims (13, 14, 15, 16, 17)
-
Specification