Array calibration methods for sensor position and pointing errors

Abstract

In order to make an antenna array more robust to array uncertainties, this paper extends the gain/phase calibration technique proposed by Ng, Er, and Kot to the problems of bearing estimation and adaptive beamforming involving sensor position error and signal pointing error, respectively. The basic idea of this technique is that the true array steering vector is approximated in terms of the nominal one by applying the first-order Taylor series expansion, and then using the null spectrum characteristics of the MUSIC algorithm; the steering vector error containing the information on the array error can be obtained by solving a set of constrained minimization formulations. For sensor position error, a calibration signal is used to impinge upon an array at two different angles. As for pointing error, we impose the orthogonal property between the transformed steering vectors of the signal and jammers on the calibration method. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 132–137, 2000.