In an approach to improve detecting and identifying objects through orbital synthetic aperture radar satellites, embodiments arrange an array of elements in a predetermined configuration, and process, by a threshold and signature analysis, detected peaks in processed image data. Further, embodiments generate a list of objects detections based on the processed peaks, and identify an object based on amplitude, polarization ration, and polarization phase difference. Additionally, embodiments, classify the identified object based on the generated list of objects, and output, by a user interface, a list of probable object detections with position coordinates and identifications based on the classified identified objects, wherein the list of probable objects are above or within a predetermine threshold of confidence.

A multi-frequency folded lens antenna structure includes a stack, and the stack includes a polarization-dependent trans-reflector, a dielectric gap, and a multi-frequency twist-reflector; wherein the polarization-dependent trans-reflector is configured to transmit electromagnetic radiation of a first polarization incident from within the stack out of the stack and to reflect electromagnetic radiation of a second, different polarization incident within the stack towards the multi-frequency twist-reflector, and the multi-frequency twist-reflector is configured to selectively change a polarization of the reflected electromagnetic radiation from the second polarization to substantially the first polarization and to direct the electromagnetic radiation of substantially the first polarization, within the stack, towards the polarization-dependent trans-reflector for at least partial transmission out of the stack, wherein the multi-frequency twist-reflector is configured to selectively change the polarization for at least a first frequency band and for at least a second frequency band, non-contiguous to the first frequency band.

A multi-frequency folded lens antenna structure includes a stack, and the stack includes a polarization-dependent trans-reflector, a dielectric gap, and a multi-frequency twist-reflector; wherein the polarization-dependent trans-reflector is configured to transmit electromagnetic radiation of a first polarization incident from within the stack out of the stack and to reflect electromagnetic radiation of a second, different polarization incident within the stack towards the multi-frequency twist-reflector, and the multi-frequency twist-reflector is configured to selectively change a polarization of the reflected electromagnetic radiation from the second polarization to substantially the first polarization and to direct the electromagnetic radiation of substantially the first polarization, within the stack, towards the polarization-dependent trans-reflector for at least partial transmission out of the stack, wherein the multi-frequency twist-reflector is configured to selectively change the polarization for at least a first frequency band and for at least a second frequency band, non-contiguous to the first frequency band.

This disclosure relates generally to methods and systems for designing an optimal dual-band metamaterial polarization converter for refractive index sensing applications. Most of the existing techniques for designing the metamaterial-based polarization converters operating at very high frequency range limits the sensing performance and increases fabrication complexity. In the design of the optimal dual-band metamaterial polarization converter, first a circular split-ring resonator (SRR) as a unit cell is designed. Secondly, the two capacitive gaps of the top layer, are aligned at 180 degrees with respect to each other and at 45 degrees with respect to X-axis and Y-axis. Lastly, step-by-step tuning the one or more key design parameters of the SRR, is performed until an optimum frequency response is obtained, to obtain the optimal dual-band metamaterial polarization converter.

A multiple band phase shifter includes a first dielectric layer, a conductive layer, a second dielectric layer, and for each central operating frequency of a plurality of central operating frequencies, a switch, a plurality of vias, and a conducting pattern layer. Each via is formed of a conductive material that extends through the first dielectric layer, through a third dielectric material formed in and through the conductive layer, and through the second dielectric layer and is connected to a first throw arm or a second throw arm of the switch. The conducting pattern layer includes conductors electrically connected to a distinct via. An electric polarization of a reflected electromagnetic wave is rotated by 90 degrees when the switch is positioned in the first conducting position and the electric polarization of the reflected electromagnetic wave is rotated by 90 degrees when the switch is positioned in the second conducting position.

An imaging system includes a first camera and a second camera. A first antenna arrangement collects image light from a first scene as seen by the first camera, and a second antenna arrangement collects image light from a second, different scene as seen by the second camera. The first antenna arrangement includes a first polarized dish antenna and the second antenna arrangement includes a second polarized dish antenna. The first camera and the second camera are supported with a first polarization of the first polarized dish antenna orthogonal to a second polarization of the second polarized dish antenna such that at least some of the image light from the first scene travels through the second polarized dish antenna to reach the first camera and at least some of the image light from the second scene travels through the first polarized dish antenna to reach the second camera.

Millimeter wave imaging devices are provided. A millimeter wave imaging device includes a housing and one or more heating elements inside the housing. The millimeter wave imaging device includes a flexible gasket on the housing. The millimeter wave imaging device includes a main lens attached to the housing by the flexible gasket. The millimeter wave imaging device includes a protective lens on an outer surface of the main lens. Moreover, the millimeter wave imaging device includes an Electromagnetic Impulse (EMI) filter attached to the housing and extending along an inner surface of the main lens. Methods of operating millimeter wave imaging devices are also provided.

The present invention is a radio signal transmitting antenna (10) including a first wave source (11) including a plurality of antenna elements (A1 to AN) configured to form a first helical beam (H) for OAM (Orbital Angular Momentum) from the plurality of antenna elements (A1 to AN) and output the first helical beam (H) and a second wave source (15) configured to receive the first helical beam (H) and form a second helical beam (L) output in a constant direction and transmits the second helical beam (L). The radio signal transmitting antenna (10) can transmit a helical beam (L) for OAM with a simplified and smaller device configuration.

The present invention is a radio signal transmitting antenna (10) including a first wave source (11) including a plurality of antenna elements (A1 to AN) configured to form a first helical beam (H) for OAM (Orbital Angular Momentum) from the plurality of antenna elements (A1 to AN) and output the first helical beam (H) and a second wave source (15) configured to receive the first helical beam (H) and form a second helical beam (L) output in a constant direction and transmits the second helical beam (L). The radio signal transmitting antenna (10) can transmit a helical beam (L) for OAM with a simplified and smaller device configuration.

A multiple band phase shifter includes a first dielectric layer, a conductive layer, a second dielectric layer, and for each central operating frequency of a plurality of central operating frequencies, a switch, a plurality of vias, and a conducting pattern layer. Each via is formed of a conductive material that extends through the first dielectric layer, through a third dielectric material formed in and through the conductive layer, and through the second dielectric layer and is connected to a first throw arm or a second throw arm of the switch. The conducting pattern layer includes conductors electrically connected to a distinct via. An electric polarization of a reflected electromagnetic wave is rotated by 90 degrees when the switch is positioned in the first conducting position and the electric polarization of the reflected electromagnetic wave is rotated by 90 degrees when the switch is positioned in the second conducting position.