Abstract: A dual-polarization, circularly-polarized artificial-impedance-surface antenna has two adjacent tensor surface-wave waveguides (SWGs), a waveguide feed coupled to each of the two SWGs and a hybrid coupler having output ports, each output port of the hybrid coupler being connected to the waveguide feeds coupled to the two SWGs, the hybrid coupler, in use, combining the signals from input ports of the 90° hybrid coupler with phase shifts at its output ports.

Abstract: A cavity-backed slot antenna whose cavity has an artificial magnetic conductor (AMC) disposed therein, the AMC being loaded with active reactive elements. The active reactive elements are preferably formed by Non-Foster Circuits (NFCs).

Abstract: A dielectric artificial impedance surface antenna (DAISA) including a first dielectric with a thickness, the first dielectric thickness varying to provide a modulated impedance to a signal traversing the first dielectric, the first dielectric having a first surface and a second surface opposite the first surface, and a transparent conductive material coating the second surface.

Abstract: A method for fabricating and installing an artificial impedance surface antenna (AISA) includes locating a substantially flat surface having a line of sight to a satellite or satellites of interest, determining an angle ?o between a normal to the substantially flat surface and a direction to the satellite or satellites of interest, selecting an antenna superstrate from a pre-fabbed stock of antenna superstrates, the selected antenna superstrate configured for having a peak radiation within two (2) degrees of the angle ?o, laminating the selected antenna superstrate to an antenna substrate to form the AISA, and mounting the AISA on the substantially flat surface.

Abstract: A surface-wave waveguide may include a base conductive ground plane including opposite side edges and a pair of conductive side walls. One conductive side wall extends from each side edge of the conductive ground plane. The surface-wave waveguide may also include a substrate including a dielectric material disposed on the base conductive ground plane and between the conductive side walls. The surface-wave waveguide may also include an impedance sheet disposed on the substrate and between the conductive side walls. The impedance sheet may include a predetermined impedance characteristic for transmitting an electromagnetic wave.

Abstract: An apparatus for measuring material properties of a material under test includes a transmission line, a tunable cavity within the transmission line having a ground plane at an end of the tunable cavity, and a voltage-tunable reactive grid adjacent a beginning of the tunable cavity.

Abstract: An active artificial magnetic conductor includes an array of unit cells, each unit cell including a top face, at least one wall coupled to the top face, a base coupled to the at least one wall, and a crossed slot in the top face. The top face, the at least one wall, and the base form a cavity and are conductive.

Abstract: A method and apparatus for electronically steering an antenna system. The apparatus comprises a dielectric substrate, a plurality of radiating spokes, and a number of surface wave feeds. The plurality of radiating spokes is arranged radially with respect to a center point of the dielectric substrate. Each radiating spoke in the plurality of radiating spokes forms a surface wave channel configured to constrain a path of a surface wave. Each of the number of surface wave feeds couples at least one corresponding radiating spoke in the plurality of radiating spokes to a transmission line that carries a radio frequency signal.

Abstract: A flexible, printable antenna for automotive radar. The antenna can be printed onto a thin, flexible substrate, and thus can be bent to conform to a vehicle body surface with compound curvature. The antenna can be mounted to the interior of a body surface such as a bumper fascia, where it cannot be seen but can transmit radar signals afield. The antenna can also be mounted to and blended into the exterior of an inconspicuous body surface, or can be made transparent and mounted to the interior or exterior of a glass surface. The antenna includes an artificial impedance surface which is tailored based on the three-dimensional shape of the surface to which the antenna is mounted and the desired radar wave pattern. The antenna can be used for automotive collision avoidance applications using 22-29 GHz or 76-81 GHz radar, and has a large aperture to support high angular resolution of radar data.

Abstract: A steerable artificial impedance surface antenna steerable in phi and theta angles including a dielectric substrate, a plurality of metallic strips on a first surface of the dielectric substrate, the metallic strips spaced apart across a length of the dielectric substrate and each metallic strip extending along a width of the dielectric substrate, and surface wave feeds spaced apart along the width of the dielectric substrate near an edge of the dielectric substrate, wherein the dielectric substrate is substantially in an X-Y plane defined by an X axis and a Y axis, wherein the phi angle is an angle in the X-Y plane relative to the X axis, and wherein the theta angle is an angle relative to a Z axis orthogonal to the X-Y plane.

Abstract: An apparatus comprising a plurality of radiating elements and a plurality of surface wave feeds. Each radiating element in the plurality of radiating elements comprises a number of surface wave channels in which each of the number of surface wave channels is configured to constrain a path of a surface wave. A surface wave feed in the plurality of surface wave feeds is configured to couple a surface wave channel in the number of surface wave channels of a radiating element in the plurality of radiating elements to a transmission line configured to carry a radio frequency signal.

Abstract: An active artificial magnetic conductor includes a ground plane and an array of unit cells coupled to the ground plane. Each unit cell includes a low impedance shunt coupled to the ground plane and an impedance element coupled to the low impedance shunt. A plurality of non Foster circuits are coupled in two different directions between impedance elements of adjacent neighboring unit cells in the array of unit cells.

Abstract: A circularly polarized artificial impedance surface antenna (AISA) includes an impedance modulated substrate having a modulated scalar impedance to a surface wave traversing a top surface of the substrate, wherein the impedance modulation has a plurality of intertwined lines of constant impedance, and wherein each line of constant impedance follows a spiral elliptical path.

Abstract: A flexible, printable antenna for automotive radar. The antenna can be printed onto a thin, flexible substrate, and thus can be bent to conform to a vehicle body surface with compound curvature. The antenna can be mounted to the interior of a body surface such as a bumper fascia, where it cannot be seen but can transmit radar signals afield. The antenna can also be mounted to and blended into the exterior of an inconspicuous body surface, or can be made transparent and mounted to the interior or exterior of a glass surface. The antenna includes an artificial impedance surface which is tailored based on the three-dimensional shape of the surface to which the antenna is mounted and the desired radar wave pattern. The antenna can be used for automotive collision avoidance applications using 22-29 GHz or 76-81 GHz radar, and has a large aperture to support high angular resolution of radar data.

Abstract: A surface-wave waveguide may include a base conductive ground plane including opposite side edges and a pair of conductive side walls. One conductive side wall extends from each side edge of the conductive ground plane. The surface-wave waveguide may also include a substrate including a dielectric material disposed on the base conductive ground plane and between the conductive side walls. The surface-wave waveguide may also include an impedance sheet disposed on the substrate and between the conductive side walls. The impedance sheet may include a predetermined impedance characteristic for transmitting an electromagnetic wave.

Abstract: A dual-polarization, circularly-polarized artificial-impedance-surface antenna has two adjacent tensor surface-wave waveguides (SWGs), a waveguide feed coupled to each of the two SWGs and a hybrid coupler having output ports, each output port of the hybrid coupler being connected to the waveguide feeds coupled to the two SWGs, the hybrid coupler, in use, combining the signals from input ports of the 90° hybrid coupler with phase shifts at its output ports.

Abstract: An active artificial magnetic conductor includes an array of unit cells, each unit cell including a top face, at least one wall coupled to the top face, a base coupled to the at least one wall, and a crossed slot in the top face. The top face, the at least one wall, and the base form a cavity and are conductive.

Abstract: An active artificial magnetic conductor includes an array of unit cells, each unit cell including a top face, at least one wall coupled to the top face, a base coupled to the at least one wall, and a crossed slot in the top face. The top face, the at least one wall, and the base form a cavity and are conductive.

Abstract: An active artificial magnetic conductor includes a ground plane and an array of unit cells coupled to the ground plane. Each unit cell includes a low impedance shunt coupled to the ground plane and an impedance element coupled to the low impedance shunt. A plurality of non Foster circuits are coupled in two different directions between impedance elements of adjacent neighboring unit cells in the array of unit cells.

Abstract: A circularly polarized artificial impedance surface antenna (AISA) includes an impedance modulated substrate having a modulated scalar impedance to a surface wave traversing a top surface of the substrate, wherein the impedance modulation has a plurality of intertwined lines of constant impedance, and wherein each line of constant impedance follows a spiral elliptical path.