Paratek Microwave Incorporated

Blackberry Corporation

Nicolaas Du Toit

Louise C Sengupta

Greg Mendolia

John Kvarnstrand

Bing Foo

Xubai Zhang

Cornelis Frederik Du Toit

Jason Sun

Cornelius Du Toit

In an embodiment of the present invention is provided a varactor comprising a substrate, a plurality of bottom electrodes positioned on a surface of the substrate separated to form a gap therein, a tunable dielectric material positioned on the surface of the substrate and within the gap, the tunable dielectric at least partially overlaying the plurality of electrodes, and a top electrode in contact with the tunable dielectric.

Varactors including interconnect layers

An embodiment of the present invention provides a method of modeling electrostrictive effects and acoustic resonances in a tunable capacitor, comprising adjusting empirically the characteristic impedances and complex propagation constants to account for actual process variations in manufacturing of the tunable capacitor; adjusting empirically the characteristic impedances and complex propagation constants to account for end-effects in the directions transversal to the wave direction; and modeling the electrostrictive effect by dividing a BST layer of the tunable capacitor into thin layers or slices with each slice's thickness representing a small fraction of an acoustic wavelength and injecting at each junction between slices, an acoustic current proportional to the electrical current through the voltage tunable capacitor.

Method of modeling electrostrictive effects and acoustic resonances in a tunable capacitor

An embodiment of the present invention provides a method of mitigating third order inter-modulation distortion in electronic circuits, comprising estimating an IP3 of the circuits using an empirical equation which includes at least one or more of the factors IP3&#x2dc;IP3o&#x2212;20 log Q+10 log F+10 log C&#x2212;17.3 log k dBm and optimizing one or more of the factors such that the third order inter-modulation distortion is mitigated.

Method and apparatus capable of mitigating third order inter-modulation distortion in electronic circuits

An embodiment of the present invention provides an RFID tag reading system, comprising an antenna system associated with a portal through which said RFID tag may pass, said antenna system comprising: a plurality of non-uniformly spaced antenna elements arranged substantially linearly; a power divider for dividing transmit power thereby coupling signals to said plurality of antenna elements; and a beamforming network capable of phase shifting the signals between the power divider and the plurality of antenna elements such that radiated signals from each antenna element add coherently such that the radiated electromagnetic energy is focused at a focal point in the near field region or in the Fresnel region of said antenna system.

RFID tag reading system and method

An apparatus capable of tracking a target, comprising at least one near-field focused antenna comprising an array of elements and a phase shifter to form multiple fixed beams in the near-field, a sensor capable of sensing the location of the target, and a controller capable of accepting position information and capable of activating the proper fixed beam along a course so as to enable the near-field focused beams to track the target. The array of elements may be substantially linear and the sensor may be optical, mechanical, thermal, or sonic position detection subsystems.

Tracking apparatus, system and method

A voltage controlled oscillator incorporating voltage tunable capactiors, comprising at least one resonator coupled into a base circuit of a bipolar transistor, said at least one resonator including at least one voltage tunable capacitor. The bipolar transistor includes a collector which terminates in a radial micro strip stub and an emitter which produces an output via an impedance matching circuit. Also, included is an integral switch mode power supply providing power to said base circuit via a first power supply filter, and to a controller via a second power supply filter. The controller scales the user-selected control voltage range to the levels required by said voltage tunable capacitors associated with said at leat one resonator.

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Columbia, MD, United States of America

Nicolaas Du Toit