Watkins- Johnson Company

Triquint Semiconductor Corporation

Wj Communications, Inc.

John Vincent Bellantoni

John S Tobias

Jeffrey Charles Allard

Thomas Paul Spivey

Embodiments of circuits, apparatuses, and systems for a protection circuit having a control element with an attenuation state to protect against overload conditions. Other embodiments may be described and claimed.

Input-power overload-protection circuit

The embodiments of the present invention provide a directional coupler switchable between a normal state and a bypass state. In one embodiment, the directional coupler comprises shunt switches for switching between the normal state and the bypass state, and first and second transmission lines each extending between first and second ends, wherein the shunt switches comprises a first switch coupled to the first end of the first transmission line, a second switch coupled to the first end of the first transmission line, and a third switch coupled between the second end of the first transmission line and the second end of the second transmission line.

Switchable directional coupler for use with RF devices

The embodiments of the present invention provide a configurable homodyne/heterodyne RF receiver including first and second mixers. The configurable homodyne/heterodyne RF receiver functions as a homodyne receiver when the first and second mixers are configured to operate in parallel, and as a heterodyne receiver when the first and second mixers are configured to operate in series. The embodiments of the present invention further provides an RFID reader employing the configurable homodyne/heterodyne RF receiver to facilitate a listen-before-talk function.

Configurable homodyne/heterodyne radio receiver and RFID reader employing same

The present invention provides sensitivity enhancement for a single antenna RFID interrogating device by separately coupling a nulling signal formed using a portion of a transmit signal into a receiver. The phase and amplitude of nulling signal can be adjusted so that the nulling signal cancels that a reflected transmit signal from the antenna, resulting in the small backscattered signal from the distant RFID tag to be more easily detected, and improving the sensitivity of the RFID receiver.

System and method for sensitivity optimization of RF receiver using adaptive nulling

An RFID reader accessible thorough a personal computer and includes a PC card interface and a controller both operating according to clock signals from a crystal oscillator. The RFID reader further includes a linearized power amplifier modulator in a transmit path, a receive chain capable of demodulating either class_1 or class _0 signals from RFID tags, and an integrated switching device for selecting one of a plurality of antenna for transmitting or receiving RF signals.

Integrated switching device for routing radio frequency signals

An RFID reader accessible thorough a personal computer and includes a PC card interface and a controller both operating according to clock signals from a crystal oscillator. The RFID reader further includes a linearized power amplifier modulator in a transmit path, a receive chain capable of demodulating EPCglobal Class_1 and Class_0 signals from RFID tags, and an integrated switching device for selecting one of a plurality of antenna for transmitting or receiving RF signals.

Multiprotocol RFID reader

A connector assembly for detachably connecting a coaxial transmission line connector to a strip lead formed on a printed wiring board is disclosed. The connector assembly includes a metallic housing to house a printed wiring board circuit having a micro-strip defined by a lead on one surface of the board and a ground plane on the other surface of the board. The housing includes a low-impedance, coaxial line section formed by an opening extending through one wall of the housing and a center conductor supported in the opening by a dielectric sleeve. A connector with a lead connected to the micro-strip lead and a body with a central insulated socket spaced from a ground plane on the surface of the board forms a transmission line section. The center conductor is slidably received in the socket, whereby the coaxial connector can be easily attached to connect the printed wiring board to the coaxial transmission line.

Connector assembly for detachably connecting a printed wiring board to a

An electrical impulse suppressor comprising a band pass filter formed with strip transmission lines adapted to attenuate the flow of energy therethrough above and below a band limited range of frequencies. The suppressor used the impedance of a discharge means connected to a strip transmission live element to form the first of two resonant circuits used in the construction of the band pass filter.

Electromagnetic impulse suppression curcuit

A high frequency hermetically sealed electrical feed through connector extending through an electronic device package for efficiently coupling a signal transmitted through the connector. The connector feeds through an opening in the wall of the package, and generally comprises three coaxial transmission line sections, the first line section being defined by a section of the wall opening having a predetermined diameter, an axial lead and a dielectric sleeve. The second line section is defined by the axial lead and a section of the wall having a larger diameter than the predetermined diameter. The third line section is defined by the axial lead and a section of the wall having a reduced diameter.

High frequency hermetically sealed electrical feed through connector

A connector assembly for detachably connecting a coaxial transmission line to a micro-strip lead formed on a printed wiring board is disclosed.

Connector asembly for detachably connecting a printed wiring board to a

High-frequency limiter and switch-limiter circuits having reduced insertion loss and improved recovery time are disclosed herein. The high-frequency switch-limiter includes at least one input port and a high-frequency signal path between the input port and a common arm. An input diode generates a first bias current in response to incidence upon the input port of high-energy signals in excess of a predefined power level. A set of protection diodes reflects the high-energy signals upon being switched to an ON state by a portion of the first bias current or by a second bias current, with the protection diodes being disposed to reflect signal energy propagated by the high-frequency signal paths when in the ON state and to pass signal energy propagated by the high-frequency signal paths when in an OFF state. Switching of the protection diodes between the ON and OFF states is expedited by modifying the impedance of a bias network included within a driver network, wherein the driver network is disposed to generate the second bias current in response to a switch control signal.

Growing community of inventors

Redwood City, CA, United States of America

John Vincent Bellantoni