Dual-polarization phased array antenna with self-calibration network

Abstract

This paper proposes a new structure for the self-calibration network of dual-polarized and circular polarized phased array antennas. A rotated feeding structure is used for the low cross-polarization of dual-polarized antenna and low axial ratio of the circular-polarized antenna, and the self-calibration is performed by placing microstrip line coupler appropriately to the structure. By utilizing the symmetric structure, self-calibration is possible using only a simple root mean square (RMS) detector, and the accuracy of dual-polarized antenna self-calibration is improved by using a delta-curve. A coupler for circular polarized antenna is also proposed, which has a higher accuracy than the conventional method. Self-calibration is performed on square patch antenna and circular patch antenna using the proposed network, and the results are verified experimentally.