Qualcomm Incorporated

Anup Savla

Roger Brockenbrough

Saihua Lin

Jeongsik Yang

Ara Bicakci

Shen Wang

Thinh Cat Nguyen

Cormac S Conroy

Liang Zhao

Soumya Das

Leonid Sheynblat

Bongyong Song

Gireesh Rajendran

Jeremy H Lin

Gangadhar Burra

Prasad S Gudem

Michael Kohlmann

Jose Cabanillas

Namsoo Kim

MeeLan Lee

Mounir Youssef Bohsali

Cristian Marcu

Meelan Lee

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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An apparatus includes amplification circuitry configured to amplify a radio frequency (RF) signal. The apparatus also includes differential inductors coupled to an output of the amplification circuitry. The differential inductors include a first inductor serially coupled to a second inductor, and the differential inductors are configured to filter the RF signal and to provide a differential output.

Dual-band low noise amplifier

A method calibrates a spread spectrum receiver having a received signal strength below a noise floor. The method includes estimating an input noise power, and measuring a noise power output from the receiver. The method also includes comparing the estimated input noise power with the measured output noise power to determine at least one calibration value. The method further includes calibrating the receiver based upon the at least one calibration value.

Calibration using noise power

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

One aspect of an apparatus for wireless communications is disclosed. The apparatus includes a controller, a first transceiver, and a second transceiver. The first transceiver is configurable by the controller to support first communications through a cellular network to at least one of a packet-based network and a circuit-switched network. The second transceiver configurable by the controller to operate with the first transceiver to support first communications through the cellular network in a first mode and support second communications through an access point to the packet-based network in a second mode. In an aspect, the second transceiver is further configured to switch from the first mode to the second mode by moving its wireless connection from the cellular network to the access point while maintaining a network-layer connection to the cellular network.

Case-based radio platform for wireless network

An apparatus includes: a plurality of amplification stages, each stage comprising a cascode transistor; and a bridge circuit coupled between gate terminals of cascode transistors in two adjacent stages of the plurality of amplification stages, the bridge circuit including a plurality of diodes.

Linearized gate capacitance in power amplifiers

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

An apparatus includes a first capacitor, an inductor coupled to the first capacitor, and a second capacitor coupled to the inductor. The second capacitor is coupled to a first output of a differential amplifier.

Multi-band power amplifier

The subject matter disclosed herein relates to a system and method for processing wireless signals received from one or more communications systems. In a particular implementation, one or more signals received from one or more communication systems such as a GNSS may be processed in two or more separate wireless signal receiver paths and combined in baseband to share one analog-to-digital converter.

Hybrid multi-band receiver

According to some embodiments, an apparatus may comprise an amplifier, wherein the amplifier comprises: an output stage formed of a positive output terminal providing a positive output voltage and a negative output terminal providing a negative output voltage; a load tank coupled in parallel with the output stage and configured to filter signals received at the amplifier; and a negative resistance block coupled in parallel with the output stage and the load tank.

Method of achieving high selectivity in receiver RF front-ends

A differential low noise amplifier (LNA) involves two main amplifying transistors biased in saturation, and two cancel transistors biased in sub-threshold. In one example, the gates of the cancel transistors are coupled to the drains of main transistors, in a symmetrical and cross-coupled fashion. The main transistors are source degenerated. Because the gates of cancel transistors are not coupled to the differential input leads of the LNA, the input capacitance of the LNA is reduced. Noise introduced into the LNA output due to the cancel transistors being biased in the sub-threshold region is reduced because there are two stages. The first stage involves the main transistors, and the second stage involves the cancel transistors. By increasing the gain of the first stage and decreasing the gain of the second stage, overall LNA gain is maintained while reducing the noise that the sub-threshold biased transistors contribute to the LNA output.

Growing community of inventors

Santa Clara, CA, United States of America

Anup Savla