An angular sampling theorem for the usable frequency range of antenna array calibration measurements

For high precision direction-finding using antenna arrays, a highly-accurate calibration data set is required. This paper focuses on the sampling requirements of such data sets to ensure an accurate direction-of-arrival estimate, in which interpolation across angle and frequency is assumed. Limited discussions of the required sampling grids to mitigate aliasing can be found in the literature, but a quantified procedure to avoid aliasing has not been presented. In this paper, we establish a link between calibration angle spacing and the maximum operation frequency of the antenna array to avoid aliasing when computing direction-of-arrival estimates. Numerical evaluations show the validity of our geometric aliasing model.