Microwave antenna far-field patterns determined from infrared holograms

摘要

We describe a technique which uses field intensity patterns formed by the interference of an unknown test antenna and a known referenceantenna-holograms in the classical optical sense-for determining the far-field pattern of the unknown antenna. The field intensity is measured by acquiring an infrared picture of the temperature distribution on a resistive screen heated by incident microwave energy. THe output of the camera is processed to yield the electric field intensity on the surface of the resistive screen. Required measurements are the field patterns of the unknown antenna and two hologormas taken with relative phase differences between the reference and unknown antennas of 0 deg and 90 deg.