Impact of Alignment Errors on measured performance of Antenna in Plane Polar Near Field Test Range

This paper presents a comprehensive study on the characterization and far-field pattern correction of a Ku-band phased array antenna measured in plane polar near-field test range. The work focuses on the accurate determination of the antenna's radiation characteristics by employing phase corrections due to alignment errors and near field to far-field transformation (NFFF) algorithms. The paper details the measurement setup, data acquisition process, and the critical alignment correction procedure applied to the measured near-field phase data. By addressing the alignment errors, significant improvements in the far-field beam characteristics were achieved. The theoretical background of plane polar near-field scanning and the NFFF algorithm, along with relevant mathematical formulations, are discussed in detail. Experimental results demonstrate the effectiveness of the proposed correction method in enhancing the accuracy of far-field predictions and optimizing the performance of the phased array antenna.