Phased Array Antenna Calibration Method Experimental Validation and Comparison

Abstract

This paper investigates the calibration methods appropriate to the phased array calibration in practical measurement setups. The rotating element electric field vector (REV) method, fast amplitude-only calibration method, and complex amplitude calibration method are compared and analyzed in the same measurement setup. The objective is to investigate the robustness of the discussed algorithms with different measurement ranges, with or without the support of array element on/off operation. A 4×8 uniform rectangular array (URA) is used to validate the three different calibration methods. The measurement results indicate that array element on/off measurement in the far field is suitable to be a reference calibration method in practical setup. The REV and complex amplitude calibration methods present comparable accuracy while fast amplitude-only calibration method provides less accurate calibration results in this measurement. Further, it was demonstrated that with element on/off data available, same calibration accuracy can be achieved either in small or large measurement ranges for the three different calibration methods. However, when the element on/off data is not available, the array calibration accuracy deteriorates with small measurement range. This paper presents the method to calibrate the phased array antenna in near-field by using the element on/off data. This is a very useful method in massive production line calibration. The calibration errors of different calibration methods are analyzed. Furthermore, this paper also analyzes the uncertainty of each method.