A planar near-field measurement system of UWB antennas for medical diagnostics

The radiation pattern in the far-field of on- and in-body antennas for medical application cannot be directly measured, since the used tissue mimicking liquid results in a high signal attenuation and thus, the measurement distance is strongly limited. A planar-rectangular near-field antenna measurement system is proposed in this paper. The near-field electric field is measured and the far-field pattern is processed through NF-FF Transformation. PEG-Water solution at different concentrations can be used to emulate the dielectric properties of different tissues. This allows the characterization of the antenna in tissues mimicking liquid, under more realistic wave propagation, which will be of great help to analyze the performance of these antennas. The measurement results confirm that this measurement system is feasible to measure the radiation pattern in both E- and H-plane of the antennas.