Efficient Angle Calibration Method for Peak Beam Measurements in Transmitarray-Based Compact Antenna Test Range

Due to the explosive growth of wireless communications, cost-effective streamline measurement of wireless devices' peak beam is a highly desirable over-the-air testing demand. The directional antenna in the device under test (DUT) is usually subject to housing effects or manufacturing and assembly errors, causing deviations in its peak beam direction and imposing challenges on efficiently testing the beam peak. Regular antenna pattern measurements are time-consuming and complicated, thus, unsuitable for streamline tests. This article proposes an efficient calibration method via a transmitarray compact antenna test range (CATR). The relationship between deviation angle and received power is demonstrated, and the off-axis feed characteristics of the transmitarray CATR are analyzed, based on which a quick and convenient technique is present for the angle calibration of the maximum beam deviation. The entire calibration process requires only measuring three positions, for a linear array, without a need for extra test sites or equipment. By utilizing this method in the streamline measurements, the peak beam of the DUT antenna can be calibrated over an angular range of -30° to 30° conveniently and effectively. Experiments are conducted for verification, and results show excellent agreement with simulations.