Use of Software Defined Radio Receivers for Antenna Measurements

This paper presents a time domain antenna measurement technique that aims to measure antennas in referenceless scenarios. The technique resolves measurement challenges derived from antennas where the reference signal is not accessible, for intance in EMC or active antennas. The algorithm implemented in this work is based on the the Fast Fourier Transform of the time domain signal to estimate the power spectrum and the relative phase between measurement points. In order to do that a reference antenna is used to retrieve the phase, providing a full characterization in amplitude and phase of the electric field and allowing source reconstruction. The results demonstrate the potential of this technique for new antenna measurement systems and reveal some of the limitations of the technique to be optimized, like the undesired reflections due to the interactions between the probe and the reference antenna.