Abstract: A rapidly twisted electromagnetic accelerating structure includes a waveguide body having a central axis, one or more helical channels defined by the body and disposed around a substantially linear central axial channel, with central portions of the helical channels merging with the linear central axial channel. The structure propagates electromagnetic waves in the helical channels which support particle beam acceleration in the central axial channel at a phase velocity equal to or slower than the speed of light in free space. Since there is no variation in the shape of the transversal cross-section along the axis of the structure, inexpensive mechanical fabrication processes can be used to form the structure, such as extrusion, casting or injection molding. Also, because the field and frequency of the resonant mode depend on the whole structure rather than on dimensional tolerances of individual cells, no tuning of individual cells is needed.

Abstract: A rapidly twisted electromagnetic accelerating structure includes a waveguide body having a central axis, one or more helical channels defined by the body and disposed around a substantially linear central axial channel, with central portions of the helical channels merging with the linear central axial channel. The structure propagates electromagnetic waves in the helical channels which support particle beam acceleration in the central axial channel at a phase velocity equal to or slower than the speed of light in free space. Since there is no variation in the shape of the transversal cross-section along the axis of the structure, inexpensive mechanical fabrication processes can be used to form the structure, such as extrusion, casting or injection molding. Also, because the field and frequency of the resonant mode depend on the whole structure rather than on dimensional tolerances of individual cells, no tuning of individual cells is needed.

Abstract: A substrate integrated waveguide (SIW) slot full-array antenna fabricated employing printed circuit board technology. The SIW slot full-array antenna using either single or multi-layer structures greatly reduces the overall height and physical steering requirements of a mobile antenna when compared to a conventional metallic waveguide slot array antenna. The SIW slot full-array antenna is fabricated using a low-loss dielectric substrate with top and bottom metal plating. An array of radiating cross-slots is etched in to the top plating to produce circular polarization at a selected tilt-angle. Lines of spaced-apart, metal-lined vias form the sidewalls of the waveguides and feeding network. In multi-layer structures, the adjoining layers are coupled by transverse slots at the interface of the two layers.

Abstract: A substrate integrated waveguide (SIW) slot full-array antenna fabricated employing printed circuit board technology. The SIW slot full-array antenna using either single or multi-layer structures greatly reduces the overall height and physical steering requirements of a mobile antenna when compared to a conventional metallic waveguide slot array antenna. The SIW slot full-array antenna is fabricated using a low-loss dielectric substrate with top and bottom metal plating. An array of radiating cross-slots is etched in to the top plating to produce circular polarization at a selected tilt-angle. Lines of spaced-apart, metal-lined vias form the sidewalls of the waveguides and feeding network. In multi-layer structures, the adjoining layers are coupled by transverse slots at the interface of the two layers.

Abstract: A surface PIN (SPIN) device and a method of fabricating such a SPIN device. The SPIN device, when activated, confines carrier injection to a small volume near the surface of the device such that the device is sufficiently conductive to simulate a planar conductor. The SPIN device comprises a P+ region and an N+ region formed in an intrinsic (I) layer. The P+ and N+ regions are separated by a lateral length of intrinsic material of length L. The length L is approximately the carrier diffusion length. When DC bias is applied across the N+ and P+ regions carriers are injected into the intrinsic region at a density exceeding 1018 carriers per cubic cm. The intrinsic region is sufficiently thin to confine the carriers near the surface of the intrinsic region. As such, in the “on” state, the SPIN device simulates a conductive material. In the “off” state, the SPIN device is no longer conductive.

Abstract: A reconfigurable adaptive wideband antenna includes a reconfigurable conductive substrate for dynamic reconfigurablility of the frequency, polarization, bandwidth, number of beams and their spatial directions, and the shape of the radiation pattern. The antenna is configured as a reflect array antenna having a single broadband feed. Reflective elements are electronically painted on the reconfigurable conductive surface using plasma injection of carriers in high-resistivity semiconductors.

Abstract: A reconfigurable antenna capable of dynamic reconfigurability of several antenna parameters. Specifically, the present invention is an antenna comprising a plurality of surface PIN devices arranged in a gridlike array. Each of the SPIN devices can be individually activated or deactivated. When a SPIN device is activated, the surface of the device is injected with carriers such that a plasma is produced within the intrinsic region of the device. The plasma can be sufficiently conductive to produce conductor or metal like characteristics at the surface of the device. Various ones of the SPIN devices can be activated to electronically paint a conductive pattern upon the substrate supporting the PIN devices. Through selective activation of the SPIN devices various surface antenna patterns can be produced upon the substrate including dipoles, cross dipoles, loop antennas, Yagi-Uda type antennas, log periodic antennas, and the like.

Abstract: A planar polarizer feed network comprising a six port branch coupler having two input ports and four output ports. The output ports are designed to have the same amplitude while their phases are sequentially offset by 90 degrees when fed from a first input port or by minus 90 degrees when fed from a second input port. In one embodiment, each output port is coupled to an aperture coupled antenna array comprising four slots and four patch antenna elements. In this arrangement, an RF signal may be coupled to each of the two input ports to couple properly phased signals to each of the antenna elements to simultaneously form both right-hand and left-hand circularly polarized signal emitted from the planar array of antenna elements.

Abstract: A reconfigurable adaptive wideband antenna includes a reconfigurable conductive substrate for dynamic reconfigurablility of the frequency, polarization, bandwidth, number of beams and their spatial directions, and the shape of the radiation pattern. The antenna is configured as a reflect array antenna having a single broadband feed. Reflective elements are electronically painted on the reconfigurable conductive surface using plasma injection of carriers in high-resistivity semiconductors.

Abstract: A reconfigurable antenna capable of dynamic reconfigurability of several antenna parameters. Specifically, the present invention is an antenna comprising a plurality of surface PIN devices arranged in a gridlike array. Each of the SPIN devices can be individually activated or deactivated. When a SPIN device is activated, the surface of the device is injected with carriers such that a plasma is produced within the intrinsic region of the device. The plasma can be sufficiently conductive to produce conductor or metal like characteristics at the surface of the device. Various ones of the SPIN devices can be activated to electronically paint a conductive pattern upon the substrate supporting the PIN devices. Through selective activation of the SPIN devices various surface antenna patterns can be produced upon the substrate including dipoles, cross dipoles, loop antennas, Yagi-Uda type antennas, log periodic antennas, and the like.

Abstract: A planar polarizer feed network comprising a six port branch coupler having two input ports and four output ports. The output ports are designed to have the same amplitude while their phases are sequentially offset by 90 degrees when fed from a first input port or by minus 90 degrees when fed from a second input port. In one embodiment, each output port is coupled to an aperture coupled antenna array comprising four slots and four patch antenna elements. In this arrangement, an RF signal may be coupled to each of the two input ports to couple properly phased signals to each of the antenna elements to simultaneously form both right-hand and left-hand circularly polarized signal emitted from the planar array of antenna elements.

Abstract: A surface PIN (SPIN) device and a method of fabricating such a SPIN device. The SPIN device, when activated, confines carrier injection to a small volume near the surface of the device such that the device is sufficiently conductive to simulate a planar conductor. The SPIN device comprises a P+ region and an N+ region formed in an intrinsic (I) layer. The P+ and N+ regions are separated by a lateral length of intrinsic material of length L. The length L is approximately the carrier diffusion length. When DC bias is applied across the N+ and P+ regions carriers are injected into the intrinsic region at a density exceeding 1018 carriers per cubic cm. The intrinsic region is sufficiently thin to confine the carriers near the surface of the intrinsic region. As such, in the “on” state, the SPIN device simulates a conductive material. In the “off” state, the SPIN device is no longer conductive.

Abstract: An electronic integrated circuit which includes at least one of RF, microwave, digital and analog components connected in a desired circuit. The integrated circuit includes a substrate of a conductive material having on a surface thereof a body of a dielectric material. The dielectric body is formed of a plurality of layers of the dielectric material bonded together. A plurality of strips of a conductive material are on the surfaces of the layers of the body to form RF, analog and digital components. Discrete electronic devices are mounted on the body and connected in the circuit. Vias of a conductive material extend through the various layers of the body to electrically connect the various strips of conductive material on the layers of the body.

Abstract: A conical corrugated microwave feed horn. A conical flare section is formed at the aperture of the feed horn and a second smooth cylindrical section is formed at the throat of the feed horn. The conical flare section is formed with two regions. The first region is a corrugated conical region formed at the aperture and having a plurality of slots formed parallel to the central axis of the feed horn. Each slot in the plurality of slots has an inner surface closest to the central axis of the feed horn and an outer surface furthest from the central axis. Connecting the corrugated conical region to the cylindrical throat is a smooth conical region. The first slot adjacent the smooth conical region has first and second formed lips on the terminating end thereof. The lips are formed directed inwardly toward each other. The last slot of the plurality of slots at the aperture of the feed horn has the terminating end of the inner surface extending in length beyond the length of the outer surface.