Monostatic Reflectivity and Transmittance of Radar Absorbing Materials at 650 GHz

Helsinki Univ. of Technol., Espoo
IEEE Transactions on Microwave Theory and Techniques (Impact Factor: 2.24). 04/2008; 56(3):632 - 637. DOI: 10.1109/TMTT.2008.916881
Source: IEEE Xplore


Transmittance and monostatic reflectivity of different radar absorbing materials at 650 GHz are presented. The reflectivity was measured in plane-wave conditions in a radar cross-section (RCS) range with vertical polarization. The lowest reflectivity level (-70 dB) was achieved with commercial absorbers TK THz RAM and Firam-500 with oblique incidence angles. Floor carpets were also studied, and the reflectivity level of those was found to be sufficiently low (from -50 to -60 dB) for use in antenna test ranges. Results agree with earlier studies and indicate the applicability of the RCS method in reflectivity measurements also at 650 GHz.

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