Prediction of Near-Field Antenna Coupling in the Presence of Obstacles

Abstract

Empirically derived curves which display the effects of near-field antenna coupling in the presence of metal obstacles are presented and discussed. The changes in boresight coupling between near-field antenna pairs due to intervening sharp-edged metal sheets and round metal cylinders of various sizes located at intermediate ranges between the antennas were measured for three antenna separation ranges. The measurements were performed with each antenna pair same-sense polarized for both horizontal and vertical polarizations at C-band and X-band frequencies. The effects of various parameters such as the antenna separation distance, type of obstacle, size of obstacle, location of the obstacle between antenna pair, polarization, frequency of operation, and ratio of the transmitting aperture dimension to the receiving aperture dimension are observed in the families of empirical curves.