Abstract: An ultra-broadband transverse electromagnetic (TEM) exponential antenna in which the radiating or receiving structure comprises first and second elongated conductors have a feed end comprising first and second narrow conductor strips. At an opposite radiating or receiving end, the widths of the first and second conductors expand exponentially in the H-plane, and the spacing between the first and second conductors expands exponentially in the E-plane, thereby providing a double flared, exponentially tapered, transverse electromagnetic horn antenna. Two TEM horn design embodiments are described herein and differ only in the lauching device by which the radiating structure is fed, which converts an input unbalanced transverse electromagnetic wave into a balanced transverse electromagnetic wave. A first preferred embodiment employs a stripline infinite balun as a launching device, while a second embodiment employs a cavity backed waveguide as a launching device.

Abstract: Measurement of the transfer function of a space fed lens array antenna membrane is achieved by utilizing a low power test illumination antenna opposite the feed side, while a probe antenna undergoes raster scanning of a test window on an opposite target side. The probe antenna measures near field distribution on the target side and data developed enables the transfer function of the membrane to be measured.