Fast Antenna Characterization Improvement by Pattern Rotations

A postprocessing procedure is proposed to improve the characterization of antenna patterns from a small number of field samples. By appropriately rotating the measured pattern of the antenna under test, the sparsity of its spherical harmonic spectrum can be enhanced. Our procedure enables extracting as much information as possible from a given measurement data set and leads to a notable improvement of the antenna radiation pattern reconstruction accuracy. The best orientation of the antenna is found by testing a reduced set of angles and using Gaussian processes as interpolation approach. This postprocessing requires no modification of the measurement procedure and, therefore, no extra measurement time. The improved fast antenna characterization accuracy is validated on both the spherical near-field and far-field simulations and measurements for various types of antennas and compared with the state-of-the-art approach.