Harris Corporation

Wherenet Corporation

Widata Corporation

Ronald J Hash

Donald K Belcher

Robert W Boyd

Douglas C Bowman

Timothy C Harrington

Michael Andrew Wohl

Robert E Boyd

John Alan Eisenberg

Robert C Taylor

Daniel A Robison

William F Croswell

David J Stryker

Kurt W Wampach

Daniel A Ramirez

Mitchell Percival

David Stryker

Balun with tunable bandpass filter characteristic includes first, second and third coupling elements disposed on a substrate. The first and second coupling elements are arranged on the substrate relative to the third coupling element to couple two identical but out of phase signals to form a corresponding unbalanced signal in the third coupling element. A plurality of tunable resonator elements are distributed within an area of the substrate defined on one side by the first and second coupling elements and on an opposing side by the third coupling element. The tunable resonator elements are configured to selectively produce a bandpass filter response.

Tunable electronic circuit which converts balanced signals to unbalanced signals

Directional coupler includes a first, second and third transmission lines. Each of the first and second transmission line elements is disposed on a dielectric substrate, and has a first end and a second end. At least a portion of the first and second transmission line elements are adjacent along a path. A third transmission line element is disposed along the path between the first and the second transmission line elements and separated therefrom by a portion of the dielectric substrate. The third transmission line element is electrically connected to a ground plane disposed on a surface of the dielectric substrate opposed from the first and second transmission line elements.

Miniature wideband quadrature hybrid

An improved distributed amplifier () includes an input transmission line () terminated with an input lead configured to accept an input signal and an output transmission line () terminated with an output lead configured to output an output signal. A number of parallel amplifier cells (204) are connected to the input transmission line () and the output transmission line () that collectively amplify the input signal from the input lead to produce an amplified output signal at the output lead. A bypass switch () is connected to the input and output transmission lines (). The bypass switch () is operative to convert either the input transmission line () or the output transmission line () into a bypass line configured to bypass the parallel amplifier cells (204) of the distributed amplifier () and provide a direct path between the input and output transmission lines () to produce a bypassed output signal at the output lead.

Wideband distributed amplifier with integral bypass

A 180&#xb0; hybrid coupler () includes a first transmission line transformer () and a second transmission line transformer (). Each of the first and second transmission line transformers is comprised of a coplanar stripline structure disposed in a spiral configuration. Each of the coplanar stripline structures has a first characteristic impedance and is configured to function as a balun. A common input feed () is coupled to each of the first and second transmission line transformers. A third transmission line transformer () and a fourth transmission line transformer () are also provided. Each of the third and fourth transmission line transformers is also configured to function as a balun and is coupled to the first and second transmission line transformers.

Miniature 180 degree hybrid coupler

A radio frequency (RF) directional coupler () can include a first transmission line element () having a first end and a second end, and a second transmission line element () having a first end and a second end. The first and second transmission line elements () can be disposed in a first plane, where at least a portion of said first and said second transmission line elements () are adjacent along a path. The RF coupler () can also include a first series of conductive coupling elements () disposed along said path in a second plane parallel to the first plane and separated from said first and said second transmission line elements () by a first dielectric element (). The first and second plane can be separated by a pre-determined distance (t) to increase a capacitive coupling between the first and second transmission line elements ().

Miniature quadrature hybrid

A method and apparatus is provided for forming a printed circuit board or other panel in which an array of vias are arranged in a desired connection grid within one or more layers of the board and then the board and vias are cut to form an edge of the board where a surface of the vias is exposed. The board may be orthogonally mounted on its edge to another thin circuit board or aperture sheet with the exposed surface of each via directly connected to such other board or sheet.

Method and apparatus for electrically connecting printed circuit boards or other panels

An antenna includes antenna elements, an antenna feed assembly and at least one integrated circuit adjacent the antenna feed assembly on a side thereof opposite the antenna elements. The at least one integrated circuit is connected to the antenna elements via the antenna feed assembly. The antenna feed assembly includes a conductive base plate spaced from the antenna elements, and has feed openings therein. Spaced apart conductive posts are integrally formed with the conductive base plate as a monolithic unit, and extend outwardly therefrom toward the antenna elements. Each conductive post has at least one passageway therethrough aligned with at least one respective feed opening to define at least one antenna feed passageway. A respective elongated feed conductor extends through each antenna feed passageway.

Array antenna including a monolithic antenna feed assembly and related methods

An object tracking system for locating radio-tagged objects within a monitored environment has a plurality tag transmission readers that detect RF transmissions from the tags, and generate output signals representative of the time-of-arrival of first-to-arrive tag transmissions. An object location processor processes the first to arrive signals in accordance with a multilateration algorithm to geolocate a tag. In order to modify the operation of a tag that comes within a prescribed region of the monitored environment (such as passing through a doorway), one or more relatively short range, magnetic field proximity-based, tag-programming 'pingers', are placed proximate to the region. A magnetic field receiver on the tag detects the field generated by the pinger and causes the tag to change operation such as increase its RF transmission rate.

Proximity-based magnetic field generator for controlling operation of RF burst-transmitting tags of geolocation system

Magnetic field-based communication with an object is enhanced by generating a rotating AC magnetic field that effectively ensures magnetic field coupling with the magnetic field sensor of the object, irrespective of the orientation of the object. The rotating AC magnetic field is produced by a diverse spatial orientation (a two-dimensional arrangement) of a plurality of magnetic field coils, and the driving of those coils in a prescribed phase relationship (e.g., in phase quadrature) to realize a composite AC magnetic field that rotates (at the carrier frequency of the coil drive signal) over the entirety of the spatial coverage area.

Use of rotating magnetic field to enhance communication with RF burst-transmitting tags of object location system

An amplitude modulation (AM) based mechanism controllably alters the shape of a binary phase shift keyed (BPSK) digital spreading waveform modulated onto an RF carrier. The modulated RF carrier is amplified by a saturated RF amplifier. The spectral properties of the amplified AM-BPSK waveform, when combined with the spectral properties of a BPSK waveform modulated onto the RF carrier and amplified by another saturated RF amplifier, produces a composite BPSK-modulated RF waveform containing substantially suppressed sidelobes.

Composite BPSK/AM-BPSK based spectral suppression of out-of-band energy from saturated RF amplifier

The unwanted influence a noise-source environment upon a modulated (e.g., FSK-encoded) magnetic field-based communication system is diminished by a non-modulated AC magnetic field communication scheme that uses a demodulatorless magnetic field detector. When installed in a tag to be tracked by a geolocation system, the demodulatorless detector responds when the tag comes within a prescribed proximity of the field generator producing the non-modulated AC magnetic field. The received signal is downconverted to baseband and processed to detect a valid AC magnetic field tone and indicate whether the tag is within a prescribed proximity of the AC magnetic field source.

Ultra-sensitive magnetic field receiver capable of operating in high noise environments

A magnetic field-based tagged object information storage and retrieval system employs a spread spectrum modulated magnetic field for identifying each of a plurality of tagged objects to which spread spectrum modulation magnetic field transponders are attached. When interrogated by a tag reader, transponders embedded in plural tags generate spread spectrum modulated magnetic fields that are correlated with a reference spreading sequence in a tag reader signal processor to both detect and identify each responding tag.

Spread spectrum baseband modulation of magnetic fields for communications and proximity sensing

A non-propagating magnetic field-based communication system transmits and receives digital data within a limited coverage area environment. The system includes a compact transmitter unit, such as that contained in an 'tracking' tag affixed to an object, and a digital detector/demodulator unit. In order to generate and FSK-modulate a non-propagating magnetic field in accordance with modulation signals representative of the digital data, the transmitter unit contains a magnetic field coil and one or more capacitors controllably switched in circuit with the coil in accordance with the data, so as to change the resonant frequency of an inductor-capacitor transmitter resonant circuit. The receiver unit includes a magnetic field-sensing coil in circuit with a capacitor, to form a receiver resonant circuit that resonates at a frequency between the FSK frequencies modulated by the transmitter unit. A digital receiver/demodulator detects whether received frequencies are valid FSK frequencies and derives digital data using differences between valid detected FSK frequencies.

Data communication system harnessing frequency shift keyed magnetic field

A magnetic field excitation and detection coil arrangement is configured to produce an electrical output signal representative of a differential combination of responses from a plurality of magnetic fields, including the field emitted from the excitation coil, a response magnetic field emitted from an object-tagged transponder interrogated by the excitation coil, and other magnetic fields from extraneous sources, such as industrial machinery. This differential combination of the responses from the detection coils will contain only the desired signal (e.g., response from an object-tagged transponder), as the other far away fields cancel, and therefore produces a net output signal level for a downstream signal (transponder output) processor.

Magnetic field emission and differential receiver coil configuration for discriminating response magnetic field from transponder tag

An object orientation-independent information storage and retrieval system 'tags' an object with a compact, strip-embedded transponder containing object identification information. The transponder remains unpowered until the tagged object passes through a pulsed time-varying magnetic field generated by a tag reader. In response to a transponder coil sensing this interrogation magnetic field, the transponder extracts and stores energy from the incident field, powering up the transponder and stimulating the emission of an alternating magnetic field reply burst encoded with information stored in memory. The reply burst has the same frequency as the interrogating magnetic field burst, and is emitted by the transponder coil prior to receipt of the next interrogation burst.

Growing community of inventors

Rogersville, TN, United States of America

Ronald J Hash