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Analysis and design of metallic parabolic anechoic chamber

Anechoic chambers are used for indoor antenna measurements. The common method for anechoic chamber construction is to cover all inside walls by the electromagnetic absorbers. In this paper, a fully metallic parabolic chamber structure is presented in which the propagation of the electromagnetic waves inside the chamber is controlled and they are guided to an absorber. In the proposed method, an appropriate quiet zone with plane wave illumination is obtained and unlike ordinary anechoic chambers, the absorber usage is decreased greatly. The performance of the chamber is evaluated by simulation. The results showed that the proposed method could provide a useful technique for the indoor antenna measurements.