PhD abstract

This thesis deals with the characterization of antenna radiation patterns to improve the use of existing measurement systems. Two approaches are proposed in order to speed up the measurement of these radiation patterns, which is achieved by reducing the required number of field samples. The first one exploits the sparse spherical wave expansion of the field radiated by antennas. It only requires knowing the maximum electrical dimension of the antenna. The second approach exploits the antenna external geometry and the measurement surface shape in order to build numerically an expansion basis tailored to the characterization problem. For both techniques, the minimal number of required field samples and an estimation of the field acquisition time at the IETR facilities are given, showing their potentialities to speed up the antenna measurements. Besides, an optimization strategy of the antenna positioning in post-processing is proposed. This procedure improves the quality of the reconstructed antenna radiation pattern from a given measurement. All the proposed methods have been validated using numerical and experimental datasets from various antenna types, different operating frequency bands and measured in several facilities, demonstrating thereby their versatility and generality.

Key words

electromagnetism, metrology, antennas, sparse recovery, finite elements