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This paper describes a new coded interferometric system for sensing the physical temperature radiated from the Earth’s surface. The proposed system consists of a Compressive Reflector Antenna (CRA) coated with Metamaterial Absorbers (MMA). The CRA and the MMA are used to code the received electromagnetic field in space and in frequency, at the focal plane array. The MMA is modeled by an equivalent magneto-dielectric medium having a definite thickness. A high frequency method based on Physical Optics is used to build the sensing matrix of the system, and the inverse problem is solved using a Nesterov-based Compressive Sensing methodology. Numerical examples are carried out in order to reconstruct the physical temperature of the Earth’s surface. The performance of the proposed system is compared to that of the conventional interferometric system GeoSTAR. Preliminary results show that the metamaterial-based CRA provides comparable performance to the GeoSTAR configuration with only half of the feeding elements, while keeping the same physical aperture size for the two configurations.
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Experimental Results of a Compressive Reflector Antenna Producing Spatial Coding
This paper presents the design and fabrication of a Compressive Reflector Antenna (CRA) for high-sensing-capacity millimeter-wave imaging applications. The CRA is fabricated using additive manufacturing or 3D printing and metalized by applying silver conductive coating spray on its surface. The near-fields of the CRA are measured when it is fed by a conical horn antenna, a compressive horn antenna, and a perturbed cavity.The singular value distribution and sensing capacity of the CRA fed by the aforementioned antennas are calculated and compared.
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- Award ID(s):
- 1653671
- PAR ID:
- 10088842
- Date Published:
- Journal Name:
- 2018 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting
- Page Range / eLocation ID:
- 933 to 934
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/APUSNCURSINRSM.2018.8608304
