Qualcomm Incorporated

Broadcom Corporation

Other

Raytheon Company

Thinh Cat Nguyen

Arnoldus Venes

Jeongsik Yang

Ara Bicakci

Mohammad Bagher Vahid Far

Shen Wang

Anup Savla

Pieter Vorenkamp

Steven T Jaffe

Peter R Kinget

Frank Carr

Jesse Aaron Richmond

Cheng-Han Wang

Myles H Wakayama

Alireza Khalili

Roger Brockenbrough

Daniel J Marz

Abbas Komijani

Yashar Rajavi

Young Gon Kim

Alberto Cicalini

Charles L Vinn

Sang-Oh Lee

Yongwang Ding

David Ta-hsiang Lin

Jin S Lee

Ashkan Borna

Roger Thomas Brockenbrough

Certain aspects of the present disclosure generally relate to voltage-controlled oscillators (VCOs) using a lowered or an adjustable negative transconductance (&#x2212;g) compared to conventional VCOs. This &#x2212;gdegeneration technique suppresses the noise injected into an inductor-capacitor (LC) tank of the VCO, thereby providing lower signal-to-noise ratio (SNR) for a given VCO voltage swing, lower power consumption, and decreased phase noise. One example VCO generally includes a resonant tank circuit, an active negative transconductance circuit connected with the resonant tank circuit, and a bias current circuit for sourcing or sinking a bias current through the resonant tank circuit and the active negative transconductance circuit to generate an oscillating signal. The active negative transconductance circuit includes cross-coupled transistors and an impedance connected between the cross-coupled transistors and a reference voltage.

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A method and apparatus for minimizing transmit signal interference is provided. The method includes the steps of: receiving a signal and amplifying the received signal. The received signal is then mixed with an intermediate frequency signal to obtain a baseband modulated signal. The baseband modulated signal is first filtered in an RC filter. The resulting signal is then divided by a preselected amount and the first divided portion is sent to a main path of a biquad filter, which produces a first stage biquad filtered signal. The second portion of the divided signal is sent to an auxiliary path of the biquad filter, and produces a second filtered signal. The first and second signals are then recombined and sent to the second stage of the biquad filter, where further filtering takes place.

Architecture to reject near end blockers and transmit leakage

Low noise and low power voltage-controlled oscillator (VCO) using transconductance (gm) degeneration

A method, an apparatus, and a system product for mixing radio frequency signals are provided. In one aspect, the apparatus is configured to perform switching of switches based on first, second, third, and fourth phased half duty clock signals. The apparatus convolves a differential input signal on a differential input port with the first, second, third, and fourth phased half duty cycle clock signals to concurrently generate a differential in-phase output signal and a differential quadrature-phase output signal on a dual differential output port. The first, second, third, and fourth phased half duty cycle clock signals are of the same frequency and out of phase by a multiple of ninety degrees with respect to each other.

Fully I/Q balanced quadrature radio frequency mixer with low noise and low conversion loss

Certain aspects of the present disclosure provide methods and apparatus for compensating, or at least adjusting, for capacitor leakage. One example method generally includes determining a leakage voltage corresponding to a leakage current of a capacitor in a filter for a phase-locked loop (PLL), wherein the determining comprises closing a set of switches for discontinuous sampling of the leakage voltage; based on the sampled leakage voltage, generating a sourced current approximately equal to the leakage current; and injecting the sourced current into the capacitor.

Leakage compensation circuit for phase-locked loop (PLL) large thin oxide capacitors

Certain aspects of the present disclosure provide methods and apparatus for temperature-dependent adjustment of a resonant circuit, such as that found in a voltage-controlled oscillator (VCO). Such adjustment may be performed in an effort to compensate for the frequency drift of the resonant circuit due to temperature changes. One example adjustment circuit for temperature-dependent adjustment of a resonant circuit generally includes at least one varactor and two sets of semiconductor devices configured to apply, across the at least one varactor, a differential adjustment voltage based on an ambient temperature of the semiconductor devices to adjust a capacitance of the at least one varactor, wherein each device in the sets of semiconductor devices has a temperature-dependent junction and wherein the two sets of semiconductor devices are configured such that voltage changes of the temperature-dependent junctions in the two sets of semiconductor devices are added in the differential adjustment voltage.

Resonant circuit temperature compensation

Certain aspects of the present invention provide methods and apparatus for detecting phase shift between signals, such as local oscillating signals in adjacent transceiver paths. One example circuit for phase detection generally includes a mixer configured to mix a first input signal having a first frequency with a second input signal having a second frequency to produce an output signal having frequency components at the sum of and the difference between the first and second frequencies; a filter connected with the mixer and configured to remove one of the frequency components at the sum of the first and second frequencies, thereby leaving a DC component; and an analog-to-digital converter (ADC) (e.g., a comparator) connected with the filter and configured to determine whether the first input signal is in-phase or out-of-phase with the second input signal based on a comparison between the DC component and a reference signal.

Phase detecting circuit for interchain local oscillator (LO) divider phase alignment

An integrated communications system. A substrate having a receiver disposed on the substrate for converting a received signal to an IF signal, a digital IF demodulator disposed on the substrate and coupled to the receiver for converting the IF signal to a demodulated baseband signal, and a transmitter disposed on the substrate operating in cooperation with the receiver to establish a two way communications path.

Digital IF demodulator for video applications

Continuously tuning a transconductance. Coupling a degeneration resistance from a first source of a first transistor in a differential pair of transistors to a second source of a second transistor in the differential pair of transistors. Applying a second variable degeneration resistance in parallel to the first degeneration resistance in response to the application of a first variable control voltage. And applying a third variable degeneration resistance in parallel to the first degeneration resistance and the second degeneration resistance in response to the application of a second variable control voltage having a fixed voltage offset from the first variable control voltage.

Variable transconductance variable gain amplifier utilizing a degenerated differential pair

Variable transconductane variable gain amplifier utilizing a degenerated differential pair

A specialty eyewear device including an optical frame that carries a pair of highly reflective surfaces that permit a wearer to experience an angular offset between the direct line of vision and the effective line of vision. No refraction occurs in the performance of the device, and no image reversal takes place. Modifications of the invention allow for certain angular adjustments in the device which can both change the actual angular offset which occurs between direct and effective line of vision, and permits angular rotation of a given angular offset.

Eyewear field-of-view changer

An improved differential amplifier having circuitry to enhance the slew rate and to provide a means for nulling the offset voltage during fabrication of the amplifier as an integrated circuit. The differential amplifier comprises an input stage connected to a current mirror. A slew rate enhancement circuit injects current into selected points of the circuit when the input voltage exceeds a predetermined threshold. An offset trim circuit injects a selected amount of current into the current mirror to alter the current flow between the input stage and the current mirror, thereby reducing the offset voltage. The selected amount of current is dictated by diodes which may be permanently shorted at various stages during fabrication, both before and after the amplifier is enclosed in an IC package.

Differential amplifier

Growing community of inventors

San Jose, CA, United States of America

Thinh Cat Nguyen