Qualcomm Incorporated

Soon-Seng Lau

Stanley Slavko Toncich

Steven C Ciccarelli

Prasad S Gudem

Chiewcharn Narathong

Lai Kan Leung

Li Liu

Timothy Paul Pals

Brian George

Raghu Narayan Challa

Brian Clarke Banister

Richard Dominic Wietfeldt

Inyup Kang

Lalan Jee Mishra

Bhushan Shanti Asuri

Arash Mirbagheri

Shrenik Patel

Lennart Karl Mathe

Raymond Curtis Wallace

Thomas Domenick Marra

Wingching Vincent Leung

Arun Raghupathy

Ketan Humnabadkar

Devavrata Vasant Godbole

Juhi Saha

Aracely Williams

Phil Coan

Ching Chang Shen

Praveen-Kumar Sampath

Steven C c/o Qualcomm Incorporated Ciccarelli

Crosstalk amelioration systems and methods in a radio frequency front end (RFFE) communication system provide a host or master of an RFFE bus to monitor a weakly-driven data line in the RFFE bus while a clock line is actively providing a clock signal for trigger events at one or more slaves on the RFFE bus. If the host detects noise on the data line that looks like a sequence start condition (SSC) signal, the host further signals on the data line to negate the impact of the false SSC signal and thus avoid misinterpretation by the slaves.

Crosstalk amelioration systems and methods in a radio frequency front end (RFFE) communication system

Techniques for detecting and correcting phase discontinuity of a local oscillator (LO) signal are disclosed. In one design, a wireless device includes an LO generator and a phase detector. The LO generator generates an LO signal used for frequency conversion and is periodically powered on and off. The phase detector detects the phase of the LO signal when the LO generator is powered on. The detected phase of the LO signal is used to identify phase discontinuity of the LO signal. The wireless device may further include (i) a single-tone generator that generates a single-tone signal used to detect the phase of the LO signal, (ii) a downconverter that downconverts the single-tone signal with the LO signal and provides a downconverted signal used by the phase detector to detect the phase of LO signal, and (iii) phase corrector that corrects phase discontinuity of the LO signal in the analog domain or digital domain.

Phase detection and correction for non-continuous local oscillator generator

A dual frequency synthesizer architecture for a wireless device operating in a time division duplex (TDD) mode is disclosed. In an exemplary design, the wireless device includes first and second frequency synthesizers. The first frequency synthesizer generates a first oscillator signal used to generate a first/receive local oscillator (LO) signal at an LO frequency for the receiver. The second frequency synthesizer generates a second oscillator signal used to generate a second/transmit LO signal at the same LO frequency for the transmitter. The two frequency synthesizers generate their oscillator signals to obtain receive and transmit LO signals at the same LO frequency when the wireless device operates in the TDD mode.

Frequency synthesizer architecture in a time-division duplex mode for a wireless device

Although the duplexer in a full-duplex transceiver circuit may only be guaranteed by the duplexer manufacturer to have a transmit band rejection from its TX port to its RX port of a certain amount, and may only be guaranteed to have a receive band rejection of another amount, the actual transmit band rejection and the actual receive band rejection of a particular instance of the duplexer may be better than specified. Rather than consuming excess power in the receiver and/or transmitter in order to meet performance requirements assuming the duplexer only performs as well as specified, the duplexer's in-circuit performance is measured as part of a transmitter-to-receiver isolation determination. Transmitter and/or receiver power settings are reduced where possible to take advantage of the measured better-than-specified in-circuit duplexer performance, while still meeting transceiver performance requirements. Power settings are not changed during normal transmit and receive mode operation.

Reducing power consumption by taking advantage of superior in-circuit duplexer performance

A method for interference reduction is described. The method is implemented in a wireless device. It is determined that a page is going to be received via a secondary receiver. It is also determined that a digital-to-analog converter (DAC) image from a transmitter will cause interference with the secondary receiver when the page is received. A sampling frequency of the DAC for the transmitter is changed so that there are not any DAC images from the transmitter that will cause interference with the secondary receiver.

Dynamically changing a transmitter sampling frequency for a digital-to-analog converter (DAC) to reduce interference from DAC images

Techniques for controlling operation of control loops in a receiver are described. The operation of at least one control loop is modified in conjunction with a change in operating state, which may correspond to a change in linearity state, gain state, operating frequency, antenna configuration, etc. A change in linearity state may occur when jammers are detected and may cause bias current of analog circuit blocks to be adjusted. The at least one control loop to be modified may include a DC loop, an AGC loop, etc. The operation of a control loop may be modified by disabling the control loop or changing its time constant prior to changing operating state, waiting a predetermined amount of time to allow the receiver to settle, and enabling the control loop or restoring its time constant after waiting the predetermined amount of time.

Techniques for controlling operation of control loops in a receiver

Reducing power consumption by in-circuit measurement of receive band attenuation and/or noise

Techniques for operating a receiver to linearity performance and higher receive signal to noise ratio are described. The receiver includes one or more circuit blocks, e.g., a low noise amplifier (LNA), having discrete gain states. The gain states are selected based on switch points, with each switch point indicating a specific received signal level at which to switch from one gain state to another gain state. The switch points may be dynamically selected based on channel conditions, which may be characterized by the presence or absence or strength or frequency of jammers. A first set of switch points may be selected when jammers are detected, and a second set of switch points may be selected when jammers are not detected. The gain states are selected in accordance with the set of switch points selected for use.

Dynamic LNA switch points based on channel conditions

A method and apparatus for avoiding receiver interference is described herein. One or more potential interferers are determined and the frequency associated with the interferers is also determined A desired sampling frequency for the receiver is calculated to avoid the potential interferers.

Apparatus and method for dynamic scaling of ADC sampling rate to avoid receiver interference

System(s) and method(s) are provided for dynamically scaling switching frequencies and clock sources of switched mode power supplies (SMPSs) in a mobile station. Switching frequency is scaled to an optimal value in response to at least one of (i) a change in mode of operation for wireless communication employed by the mobile station, an additional mode of operation is triggered, (ii) a change in operation conditions of a set of loads associated with functionality of the mobile is determined, or (iii) an LO spur set-off by a SMPS in the presence of an interference signal with a frequency splitting from an operational band that matches the SMPS frequency or at least one of its harmonics. Switching frequencies can be selected from a lookup table, or through an analysis of switching frequencies available to the mobile and operational criteria. A set of clock sources can provide an ensemble of switching frequencies.

Dynamic frequency scaling of a switched mode power supply

A tunable SAW resonator circuit is disclosed. The tunable SAW resonator circuit includes a SAW resonator having a Q, a resistor coupled to the SAW resonator to reduce the Q, and a tuning component coupled to the SAW resonator to tune the SAW resonator. A method to tune the SAW resonator is also disclosed. The SAW resonator may be tuned by applying a control signal to the tuning component.

Tunable surface acoustic wave resonators

A system and method for controlling transmitted output power of autonomous hand held devices and external antenna units. Transmit power of an information signal is controlled in the hand held device utilizing multiple units for transmission. The transmit power is controlled by obtaining a temperature compensated power measurement of the information signal transmitting from the antenna unit. The temperature compensated power measurement is determined by either a software or a hardware compensation scheme. The software temperature compensation scheme involves identifying a power detector output and temperature output within the antenna unit and sending both outputs through a power estimator, where the power estimator utilizes voltage-temperature correlation equations, to produce the temperature compensated power measurement. The hardware temperature compensation scheme involves the use of a temperature compensation circuit made up of a diode pair, an amplifier, a negative temperature coefficient thermistor, and a positive temperature coefficient thermistor. The diode pair is used to provide a true average of the current power input and sends its output to the amplifier. The amplifier produces the temperature compensated power measurement, where the negative temperature coefficient thermistor increases the temperature compensated power measurement at low temperatures and the positive temperature coefficient thermistor increases the temperature compensated power measurement at high temperatures. The temperature compensated power measurement is used by the hand held device to adjust the power of the transmitted information signal.

System and method for temperature compensation of external antenna units

A system and method for controlling transmitted output power of hand held wireless devices used with external antenna units. Transmit power of information signals is controlled in the hand held device by obtaining design specification parameters of the antenna unit, which includes an output power measurement of the information signal transmitting from the antenna unit, which may also be referred to as an outdoor unit. The output power measurement is used by the hand held device, to adjust the power of the transmitted information signal. The output power measurement is determined in the antenna unit by obtaining a digital output power measurement, modulating the power measurement, and transmitting the modulated measurement signal to the hand held device. The modulated measurement signal is received by a cradle supporting the hand held device, or the device itself and demodulated. The hand held device uses the measurement to adjust the transmit power of the information signal.

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San Diego, CA, United States of America

Soon-Seng Lau