Calibration of antenna arrays for aeronautical vehicles on ground

Antenna pattern and characteristics change significantly when antenna arrays are placed on platforms like aeronautical vehicles. Calibration of antenna arrays is an important and costly process for such cases. In this paper, a method is proposed for the offline calibration of a direction finding antenna array mounted on a UH-60 helicopter. The calibration is done on an open-field test area with a flat ground plane. Ground reflections are the main sources of error corrupting the calibration data. The proposed method eliminates the ground reflections by employing a time-gating technique. Calibration data is generated by considering the platform effects. Complete calibration scenario is simulated by using numerical electromagnetic simulation tools. It is shown that the proposed approach is very effective and can be used to calibrate direction finding algorithms like the MUSIC algorithm.