Electromagnetic field analysis of a four-wire anechoic chamber

The electromagnetic field characteristics and plane-wave generating ability of a parallel four-wire anechoic chamber which is to be operated in the VHF range is analyzed. The analysis considers three cases: the first is a four-wire chamber when only a thin layer of absorber material covers the chamber walls, the second is a four-wire chamber when only free space surrounds the four wires of the system, and the third is a four-wire chamber when a thick layer of absorber material covers the anechoic chamber walls. The three cases are analyzed by a variety of mathematical methods including the method of moments, waveguide theory, and a finite-difference time-domain method. Numerical results for the propagation constants and electromagnetic fields that are generated in the chamber in the three cases are presented