Performance evaluation is an important aspect in the study of microwave-absorbing\nmaterial coatings. The reflectivity of the incident wave is usually taken as the performance indicator.\nThere have been various methods to directly or indirectly measure the reflectivity, but existing\nmethods are mostly cumbersome and require a strict testing environment. What is more, they cannot\nbe applied to field measurement. In this paper, we propose a scheme to achieve field performance\nevaluation of microwave-absorbing materials, which adopts a small H-plane sectoral horn antenna\nas the testing probe and a small microwave reflectometer as the indicator. When the size of the\nH-plane sectoral horn antenna is specially designed, the field distribution at the antenna aperture can\nbe approximated as a plane wave similar to the far field of the microwave emitted by a radar unit.\nTherefore, the reflectivity can be obtained by a near-field measurement. We conducted experiments\non a kind of ferrite-based microwave-absorbing material at X band (8.2ââ?¬â??12.4 GHz) to validate the\nscheme. The experimental results show that the reflectivity is in agreement with the reference data\nmeasured by the conventional method as a whole.
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