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A low cost millimeter-wave (mm-wave) electronically reconfigurable Reflect Array (RA) has been presented in this paper. Aperture-Coupled Patch (ACP) elements are used to forma 40×40 element reconfigurable RA operating in the 71-74 GHz range of the mm-wave band. A feeding network, integrated with Single-Pole, Single-Throw (SPST) switches is designed to adjust the phase of the reflected field for the ON/OFF state of the switch. The performance of the reconfigurable RA is evaluated by performing beam focusing at the near-field of the array. 

In this paper, a new waveguide-fed Antipodal Vivaldi Antenna (AVA) for mm-wave imaging applications is presented. A waveguide-to-broadside coupled Antipodal finline transition is designed to couple the dominant mode of a WR-12 waveguide into the AVA. The transition provides a wideband and low insertion loss in the entire E-band. A dielectric lens is added in front of the AVA to increase the directivity in theendfire direction of the antenna. The performance of the designed antenna is evaluated in the E-band in terms of its return loss,gain, and radiation pattern. 

This paper presents a norm-1 regularized algorithm, based on the Alternating Direction Method of Multipliers(ADMM), in which the sensing matrix is divided by columns. This technique is based on sectioning the imaging domain into different regions and optimizing them in distributed computational nodes.The information shared among nodes is highly reduced compared to the consensus-based ADMM, when dividing the matrix by rows. The combination of the sectioning-based ADMM with the imaging capabilities of the recently proposed Compressive Reflector Antenna allows a distributed, real-time imaging with fast node communication. 

This paper explores the use of compressive sensing (CS) methods to microwave-induced thermoacoustics (TA)imaging. Moreover, it proposes the use of a holey cavity as a mechanism to enhance the reconstruction properties of the sensing matrix. The CS imaging and the holey cavity reduce the number of measurements needed to perform the imaging, thus reducing the overall complexity of the imaging system. 

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.