Abstract: Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Some embodiments of resonant via arrays are mechanically balanced, which promotes improved manufacturability. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.

Abstract: A magnetically-loaded artificial magnetic conductor surface provides enhanced bandwidth. The structure includes in one embodiment a thumbtack structure with a spacer layer that is loaded with a barium-cobalt hexaferrite based artificial magnetic material. Specifically, the geometry consists of a ground plane covered with thinly sliced ferrite tiles that are metallized and stacked. Each tile has a metal via running through its center that is electrically connected to the plated metallized surfaces. A foam spacer layer resides above the ferrite tiles. Atop the foam spacer layer rests a capacitive surface, which can be realized as a single layer array of metal patches, a multiple layer array of overlapping patches or other planar capacitive geometry.

Abstract: Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Some embodiments of resonant via arrays are mechanically balanced, which promotes improved manufacturability. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.

Abstract: A multiband antenna includes at least two resonators that are driven directly and resonate in different frequency bands and a parasitically coupled resonator that resonates in one of the frequency bands. The coupled resonator is grounded with a conductive trace at one end and is thus not directly fed by the RF feed of the antenna. The coupled resonator increases the efficiency bandwidth near the frequency of operation for the coupled resonator. The antenna is fabricated from a stamped metal that is bent around or overmolded by a spacer layer. A clip formed integrally with the antenna by bending a portion of the ground plane permits attachment to the metal shield of the display of a laptop computer and is thus grounded along its length.

Abstract: Apparatus for suppressing noise and electromagnetic coupling in the printed circuit board of an electronic device includes an upper conductive plate and an array of conductive coplanar patches positioned a distance t2 from the upper conductive plate. The distance t2 is chosen to optimize capacitance between the conductive coplanar patches and the upper conductive plate for suppression of noise or electromagnetic coupling. The apparatus further includes a lower conductive plate a distance t1 from the array of conductive coplanar patches and conductive rods extending from respective patches to the lower conductive plate.

Abstract: Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Some embodiments of resonant via arrays are mechanically balanced, which promotes improved manufacturability. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.

Abstract: Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Particular embodiments include clusters of small vias that effectively function as one large via, thereby increasing stop band bandwidth and maximizing parallel plate capacitance. Cluster vias can be configured to additionally provide a shielded and impedance matched route within the interior area of the cluster through which signal vias can connect transmission lines disposed in planes lying above and below the PPW. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.

Abstract: DC inductive FSS technology is a printed slow wave structure usable for reduced size resonators in antenna and filter applications of wireless applications. It is a dispersive surface defined in terms of its parallel LC equivalent circuit that enhances the inductance and capacitance of the equivalent circuit to obtain a pole frequency as low as 300 MHz. The effective sheet impedance model has a resonant pole whose free-space wavelength can be greater than 10 times the FSS period. A conductor-backed DCL FSS can create a DC inductive artificial magnetic conductor (DCL AMC), high-impedance surface with resonant frequencies as low as 2 GHz. Lorentz poles introduced into the DCL FSS create multi-resonant DCL AMCs. Antennas fabricated from DCL FSS materials include single-band elements such as a bent-wire monopole on the DCL AMC and multi-band (dual and triple) shorted patches, similar to PIFAs with the patch/lid being a DCL FSS.

Abstract: Lightweight, small antennas are described that have decreased material and fabrication/processing cost. The antennas may be used in consumer electronics products such as cellular phones, laptops and PDA's. Some of the antennas and fabrication techniques also provide lower part count and increased reliability. All antennas are fabricated with standard materials currently available in high volume production.

Abstract: An electromagnetic bandgap material is electrically attached to an edge, and enables high isolation between antennas due to the attenuation of surface waves. The disclosed embodiments further provide narrow reactive edge treatments in the form of artificial magnetic conductors (AMCs) whose physical width is less than 1/10 of a free space wavelength for the frequency of surface currents intended to be suppressed. These embodiments still further provide several AMCs suitable for this purpose, along with several exemplary manufacturing techniques for the AMCs.

Abstract: A low profile antenna system includes an artificial magnetic conductor comprising a frequency selective surface (FSS) having an effective sheet capacitance which is electronically variable to control resonant frequency of the AMC and the resonant frequency of an antenna element positioned adjacent to the FSS.

Abstract: An antenna comprises a conductive member having an opening for radiating an electromagnetic signal. A circuit board is spaced apart from the conductive member by less than one-quarter wavelength of the electromagnetic signal. The circuit board has a series of conductive cells for suppressing at least one propagation mode propagating between the conductive member and circuit board over a frequency bandwidth range defined by a geometric arrangement of the conductive cells.

Abstract: An electronically reconfigurable artificial magnetic conductor (RAMC) includes a frequency selective surface (FSS) having an effective sheet capacitance which is variable to control resonant frequency of the RAMC. In one embodiment, the RAMC further includes a conductive backplane structure and a spacer layer separating the conductive backplane structure and the FSS. The spacer layer includes conductive vias extending between the conductive backplane structure and the FSS, and voltage variable capacitive circuit elements coupled with the FSS and responsive to bias voltages applied on one or more bias signal lines routed through the conductive backplane structure and the conductive vias.

Abstract: A direct current (DC) inductive shorted patch antenna includes a direct current inductive (DCL) frequency selective surface (FSS) forming the radiating element, a ground plane, a feed, and a radio frequency (RF) short to the ground plane positioned between the feed and the radiating element.

Abstract: A combined antenna and electromagnetic shield include a dielectric body mountable to a printed circuit board (PCB), antenna metallization disposed on a first side of the dielectric body and shield metallization disposed on a second side of the dielectric body. The shield metallization serves both as a ground plane for the antenna metallization and as an electromagnetic interference shield for circuit and components on the PCB below. Physical parameters of the component, such as thickness and composition, can be designed to tailor the performance of the antenna formed by the device. Antenna height can be defined by an injection mold, which dramatically reduces variability in the performance of production antennas.

Abstract: A microstrip trombone delay line is used to provide a low cost true time delay device. An array of printed trombone lines arranged in a network is used to implement a linear beamformer. The beamformer forms an array that scans signals in one or more dimensions. Each microstrip trombone delay line includes printed traces on a fixed substrate and a printed trombone line on a movable superstrate. The microstrip trombone delay line may have different dimensions to vary the characteristic impendence at either end for impedance matching purposes. Beamformers using microstrip trombone delay lines and scanning in multiple principal planes require few movable parts and only linear actuators.

Abstract: An artificial magnetic conductor is resonant at multiple resonance frequencies. The artificial magnetic conductor is characterized by an effective media model which includes a first layer and a second layer. Each layer has a layer tensor permittivity and a layer tensor permeability having non-zero elements on the main tensor diagonal only.

Abstract: A multi-band artificial magnetic conductor (AMC) is described in an electrically small antenna for use in handheld wireless devices and base station antenna applications. The multi-band AMC contains a ground plane, two or more frequency selected surfaces (FSS) having periodic conductive patches disposed on opposing surfaces and a dielectric layer sandwiched between the surfaces, and dielectric layers between the FSS layers and between the lower FSS layer and the ground plane. Various parameters of the dual band AMC are chosen such that the AMC has non-harmonically related resonant frequencies within two or more different frequency bands.

Abstract: An antenna consisting of a thin strip bent-wire monopole disposed on an artificial magnetic conductor (AMC) is loaded at the end opposite to the feed point with a distributed or lumped capacitance to achieve an electrically small antenna for use in handheld wireless devices. The capacitive load reduces the length of the antenna to smaller than one-quarter of a wavelength at a given frequency of operation without suffering a substantial loss of efficiency. This results in an easier integration into portable devices, greater radiation efficiency than other loaded antenna approaches and longer battery life in portable devices, and lower cost than use of a chip inductor.

Abstract: In an artificial magnetic conductor, the distance between the frequency selective surface and the ground plane is mechanically varied to adjust the effective inductance or capacitance of the structure and thus the resonant frequency of the device.