Progress In Electromagnetics Research
ISSN: 1070-4698, E-ISSN: 1559-8985
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By M. Canavero and A. Murk

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High reflective materials in the microwave region play a very important role in the realization of antenna reflectors for a broad range of applications, including radiometry. These reflectors have a characteristic emissivity which needs to be characterized accurately in order to perform a correct radiometric calibration of the instrument. Such a characterization can be performed by using open resonators, waveguide cavities or by radiometric measurements. The latter consists of comparative radiometric observations of absorbers, reference mirrors and the sample under test, or using the cold sky radiation as a direct reference source. While the first two mentioned techniques are suitable for the characterization of metal plates and mirrors, the latter has the advantages to be also applicable to soft materials. This paper describes how, through this radiometric techniques, it is possible to characterize the emissivity of the sample relative to a reference mirror and how to characterize the absolute emissivity of the latter by performing measurements at different incident angles. The results presented in this paper are based on our investigations on emissivity of a multilayer insulation material (MLI) for space mission, at the frequencies of 22 and 90 GHz.

M. Canavero and A. Murk, "Radiometric Method for Emissivity Retrieval in High Reflective Materials," Progress In Electromagnetics Research, Vol. 143, 187-206, 2013.

1. Kasparek , et al., "Measurements of ohmic losses of metallic re°ector at 140 GHz using a 3-mirror technique," International Journal of Infrared and Millimeter Waves, Vol. 22, No. 11, 1695-1707, 2001.

2. Yang, B. B., et al., "A high-Q terahertz resonator for the measurement of electric properties of conductors and low-loss dielectrics," IEEE Transactions on Terahertz Science and Technology, Vol. 2, No. 4, 449-459, 2012.

3. Van Klooster, K., et al., "Results of reflection loss measurement of sample material for radio astronomy telescope antenna for planck project," 14th Internation Crimean Conference on Microwave and Telecom Technologies , 753-755, 2004.

4. Butler, N. R., "Emissivity measurements of MAP satellite optics," Physics Dpt. Senior Thesis, 1998.

5. Duric, A., A. Magun, A. Murk, C. Matzler, and N. Kampfer, "The fully polarimetric imaging radiometer SPIRA at 91 GHz," IEEE Transactions on Geoscience and Remote Sensing, Vol. 46, No. 8, 2323-2336, 2008.

6. Straub, C., A. Murk, and N. Kampfer, "MIAWARA-C. A new ground based water vapor radiometer for measurement campaigns," Atmospheric Measurement Techniques, Vol. 3, 1-15, 2010.

7. Tschanz, B., et al., "Validation of middle atmospheric campaign-based water vapor measured by the ground-based microwave radiometer MIAWARA-C," Atmospheric Measurement Techniques Discussions, Vol. 6, 1311-1359, 2013.

8. StÄahli, O., et al., "A surface-based method for water vapour and liquid clouds using a scanning radiometer at 91 GHz," IEEE transaction on Geoscience and Remote Sensing, Vol. 40, No. 9, 3273-3280, 2011.

9. Skou, N., "Measurement of small antenna reflector losses for radiometer calibration target," IEEE Transactions on Geoscience and Remote Sensing, Vol. 35, No. 4, 967-971, 1997.

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