Phased array calibration system with high accuracy and low complexity

This paper presents a highly efficient phased array calibration system for phase and magnitude error correction. The proposed calibration system is based on far-field scanning of the array antenna under test at factory level. Since the proposed structure requires a magnitude detection only for vector calibration, low circuit complexity can be achieved. Unlike the conventional far-field calibration based on rotating-element electric-field vector (REV) method to find maximum vector-sum point, the proposed system detects the minimum vector-sum point and tracks the behavior of the null point. To verify the feasibility of the proposed system for large-scale array antenna, 4 × 4 phased array antenna is implemented at 5.8 GHz. Then, the proposed method is applied to the phased array antenna and compared with the conventional REV method.