Patent application number | Description | Published |
20080232268 | LMS Adaptive Filter for Digital Cancellation of Second Order Inter-Modulation Due to Transmitter Leakage - A transmit signal second-order inter-modulation (IM | 09-25-2008 |
20080233994 | Digital Modulator and Method for Initiating Ramp Power Transitions in a Mobile Handset Transmitter - A digital modulator for a portable handset using 8PSK or EDGE modulation with a direct launch transmitter is used to controllably adjust the transmit power of the portable handset. The digital modulator includes a controller coupled between a memory and an accumulator. The controller is responsive to an indication that the transmit power should be transitioned. The controller temporarily alters the data transferred from the memory to the accumulator during transitions of the transmit power level. | 09-25-2008 |
20110021237 | Closed-Loop Adaptive Power Control For Adjusting Bandwidth In A Mobile Handset Transmitter - A mobile handset is arranged with an adaptive power controller to controllably adjust transmit power. The adaptive power controller is coupled to a power amplifier module to form a closed feedback loop. The adaptive power control module includes a first shifter, a first sealer, an accumulator and a hold element. The first shifter and first sealer receive respective bandwidth control signals and an error signal. The first shifter and first sealer generate a modified error signal that is forwarded to and filtered by the accumulator and the hold element to generate a power control signal. The power control signal, which is generated the radio frequency subsystem of the handset can quickly and accurately track rapid changes in transmit power. | 01-27-2011 |
20110116403 | LMS Adaptive Filter for Digital Cancellation of Second Order Inter-Modulation Due to Transmitter Leakage - A transmit signal second-order inter-modulation (IM2) canceller for a portable handset using a full duplex mode of operation (e.g., WCDMA) is used to controllably reduce IM2 introduced by a transmit signal that appears in a received signal in a receive channel of the portable handset. The transmit signal IM2 canceller includes a delay estimator and a digital signal adjuster. The delay estimator receives a first input from a receive channel and a second input from a transmit channel. The delay estimator generates an estimate of the IM2 that the transmit channel introduces in the receive channel. The digital signal adjuster removes the estimate of the IM2 before forwarding a modified receive channel signal to a baseband subsystem of the portable handset. | 05-19-2011 |
20110268216 | Transmitter Gain Control and Calibration - Embodiments provide improved systems and methods of gain control and calibration for wireless transmitters. In particular, embodiments allow linear gain control over the entire transmitter gain control range, independent of temperature/process variations. Embodiments require very low power consumption compared to existing approaches. Embodiments may also be used for gain control calibration during production time, thereby substantially reducing production calibration time and cost. | 11-03-2011 |
20110306391 | Transmitter architecture enabling efficient preamplification gain control and related method - According to one embodiment, a radio frequency (RF) transceiver includes a transmitter enabling efficient preamplification gain control. The RF transceiver comprises a receiver and a power amplifier (PA) for amplifying a transmit signal of the transmitter. The transmitter is configured to provide pre-PA gain control for preamplifying the transmit signal before amplification by the PA, wherein substantially all of the pre-PA gain control is provided when the transmit signal is at a transmit frequency of the transmitter. In one embodiment, the transmitter includes a PA driver comprising in combination: a transconductance amplifier, a current steering block, and an output transformer. Each of the transconductance amplifier, current steering block, and output transformer is configured to contribute a respective variable gain control to the pre-PA gain control provided by the PA driver. | 12-15-2011 |
20120021699 | Compact low-power receiver architecture and related method - According to one embodiment, a compact low-power receiver comprises a front-end producing a front-end gain and a back-end producing a back-end gain. The front-end includes a transconductance amplifier providing digital gain control and outputting an amplified receive signal, a mixer for generating a down-converted signal from the amplified receive signal, and a transimpedance amplifier (TIA) including a current mode buffer. The TIA provides gain control for amplifying the down-converted signal to produce a front-end output signal. In one embodiment, the back end includes a second-order low-pass filter to produce a filtered signal from the front-end output signal and an analog-to-digital converter (ADC), wherein the filtered signal is fed directly to the ADC without direct-current (DC) offset cancellation being performed. In various embodiments, the front-end gain is substantially greater than the back-end gain. | 01-26-2012 |
20120077446 | Self-testing transceiver architecture and related method - A self-testing transceiver comprises a receiver, and a transmitter including a power amplifier (PA) and a plurality of transmitter pre-PA stages. The plurality of transmitter pre-PA stages are configured to generate a communication signal at a receive frequency of the transceiver and the receiver is configured to process another communication signal at a transmit frequency of the transceiver, thereby enabling transceiver self-testing. A method for use by a transceiver for self-testing comprises generating a first communication signal at a transmit frequency of the transceiver by a transmitter of the transceiver, processing the first communication signal by a receiver of the transceiver, generating a second communication signal at a receive frequency of the transceiver by the transmitter, and processing the second communication signal by the receiver. The described generating and processing of the first and second communication signals resulting in self-testing by the transceiver. | 03-29-2012 |
20120170624 | SYSTEMS AND METHODS FOR POWER CONTROL IN A MULTIPLE STANDARD MOBILE TRANSMITTER - A transmitter adjusts a transmitted power level by modifying a control input of a variable gain amplifier. A power amplifier control system includes an envelope extractor, an error extractor, and a feed-forward multiplier. The envelope extractor receives data signal inputs and computes the envelope of the combined signal. The error extractor generates an error signal as a function of the combined signal and the output power generated by the power amplifier. The feed-forward multiplier generates a modified error signal that is responsive to a function of the gain in a feedback path. A corresponding method for controlling a power level is also disclosed. In some embodiments, a transmit chain with a power control loop is used to adjust the transmit signal power applied at an input of a variable gain amplifier. A corresponding method for adjusting the transmit signal power level is also included. | 07-05-2012 |
20120250786 | DIGITAL MODULATOR AND METHOD FOR INITIATING RAMP POWER TRANSITIONS IN A MOBILE HANDSET TRANSMITTER - A digital modulator for a portable handset using 8PSK or EDGE modulation with a direct launch transmitter is used to controllably adjust the transmit power of the portable handset. The digital modulator includes a controller coupled between a memory and an accumulator. The controller is responsive to an indication that the transmit power should be transitioned. The controller temporarily alters the data transferred from the memory to the accumulator during transitions of the transmit power level. | 10-04-2012 |
20120328052 | Spur Mitigation For Radio Frequency Receivers Utilizing A Free-Running Crystal - Embodiments of a receiver for using a first oscillator signal provided by a crystal resonator to support multiple, different functionalities are provided. The receiver comprises a phase-locked loop (PLL) configured to provide a second oscillator signal based on the first oscillator signal provided by the crystal resonator; a first mixer configured to mix a received signal received over a first input path with the second oscillator signal received over a second input path to provide a first frequency-shifted signal; and an automatic frequency controller (AFC) configured to estimate a frequency offset of the second oscillator signal and adjust the PLL to compensate for the frequency offset. The receiver further can include solutions for mitigating potential sources of noise caused by the frequency of the first oscillator signal not being compensated for by the AFC. | 12-27-2012 |
20120328058 | Long-Term Drift Mitigation For Radio Frequency Receivers Utilizing A Free-Running Crystal - Embodiments of a receiver for using a first oscillator signal provided by a crystal resonator to support multiple, different functionalities are provided. The receiver comprises a phase-locked loop (PLL) configured to provide a second oscillator signal based on the first oscillator signal provided by the crystal resonator; a first mixer configured to mix a received signal received over a first input path with the second oscillator signal received over a second input path to provide a first frequency-shifted signal; and an automatic frequency controller (AFC) configured to estimate a frequency offset of the second oscillator signal and adjust the PLL to compensate for the frequency offset. The receiver further can include solutions for mitigating potential sources of noise caused by the frequency of the first oscillator signal not being compensated for by the AFC. | 12-27-2012 |
20130155911 | Radio Transceiver With IM2 Mitigation - A structure and method to reduce second order intermodulation (IM2) of a receiver in a transceiver is provided. Specifically, the output of a detector in a transmit power control loop is utilized to calculate IM2 and the value is subtracted from a receive path to mitigate IM2 in a wireless communication devices. Alternatively, the detector can be placed in one or more receive paths to include receiver front-end passband variation. | 06-20-2013 |
20130157598 | Systems and Methods for Power Sensing and Antenna Tuning - Systems and methods are provided for detecting forward power sent to an antenna and reflected power reflected back from the antenna. Embodiments of the present invention provide systems and methods for measuring forward and reflected power and controlling the amount of power supplied to the antenna responsive to these measurements. Embodiments of the present invention enable the power sent to the antenna to be dynamically altered when antenna impendence changes (e.g., when the antenna gets too close to another object). | 06-20-2013 |
20130235954 | Transmitter Gain Control and Calibration - Embodiments provide improved systems and methods of gain control and calibration for wireless transmitters. In particular, embodiments allow linear gain control over the entire transmitter gain control range, independent of temperature/process variations. Embodiments require very low power consumption compared to existing approaches. Embodiments may also be used for gain control calibration during production time, thereby substantially reducing production calibration time and cost. | 09-12-2013 |
20130267183 | Low-Power Receiver - According to one embodiment, a compact low-power receiver comprises a front-end producing a front-end gain and a back-end producing a back-end gain. The front-end includes a transconductance amplifier providing digital gain control and outputting an amplified receive signal, a mixer for generating a down-converted signal from the amplified receive signal, and a transimpedance amplifier (TIA) including a current mode buffer. The TIA provides gain control for amplifying the down-converted signal to produce a front-end output signal. In one embodiment, the back end includes a second-order low-pass filter to produce a filtered signal from the front-end output signal and an analog-to-digital converter (ADC), wherein the filtered signal is fed directly to the ADC without direct-current (DC) offset cancellation being performed. In various embodiments, the front-end gain is substantially greater than the back-end gain. | 10-10-2013 |
20140091842 | Hybrid AFC using DCXO and RF PLL - A technique to provide hybrid compensation to correct for drifts in a reference frequency output from a digitally-controlled crystal oscillator (DCXO). A first compensation is provided to the DCXO to adjust for overlap or discontinuity of the reference frequency caused by switching capacitors in the capacitor array that controls drift of the reference frequency output. The second compensation is obtained at a phase-locked loop (PLL) that receives the reference frequency signal from the DCXO. The second compensation adjusts the PLL to adjust for variations of the reference frequency that remain after performing compensation in the DCXO. | 04-03-2014 |
20140341318 | AVERAGE POWER TRACKING IN A TRANSMITTER - Average Power Tracking (APT) is a technique that can be utilized for vary the supply voltage to a power amplifier (PA) on a timeslot basis in order to reduce power consumption of the PA. Systems and methods are provided for maximizing power savings associated with the PA by utilizing APT in a continuous and aggressive manner. Additionally, the systems and methods can further compensate for variations in temperature, frequency, antenna load, and peak to average power ratio (PAPR) without sacrificing the power savings. | 11-20-2014 |
20140355526 | LOW COST AND ROBUST RECEIVER ARCHITECTURE FOR DOWN LINK CARRIER AGGREGATION - Various configurations and arrangements of systems and methods for providing multi-carrier aggregation are described. A system in accordance with the disclosure can include a first mixer configured to receive a first signal in a first frequency band, a second mixer configured to receive a second signal in a second frequency band, a third mixer configured to receive the second signal in the second frequency band, and a fourth mixer configured to receive a third signal in a third frequency band. The system can further include a controller configured to selectively activate one of the first mixer and the second mixer, and selectively activate one of the third mixer and the fourth mixer. | 12-04-2014 |
20150023450 | APPARATUS AND METHODS FOR POWER CONTROL IN MOBILE COMMUNICATION DEVICES - Apparatus and methods for power control in mobile communication devices are provided. In one aspect, a method for accurately controlling an adjustable power level of a data signal in a transmit chain of a transmitter is provided. The method includes adjusting a controllable gain level of a digital-to-analog converter based on a desired peak-to-average ratio of a transmit signal envelope, adjusting a digitally controlled discrete gain-step amplifier, the amount of gain per step based on an initial estimate of the transmitter gain and a target power, applying a factor to a gain adjuster responsive to the gain step change in the transmit chain, and repeating the adjusting and applying steps until a feedback signal level exceeds a reference signal level. | 01-22-2015 |
20150063496 | RECEIVER WITH NOISE COMPENSATION AND METHODS FOR USE THEREWITH - A receiver includes a radio frequency (RF) front end receives a received signal that is modulated via orthogonal frequency division multiplexing (OFDM) and generates a downconverted signal, based on the received signal. An OFDM demodulator generates subcarrier data based on the downconverted signal. The subcarrier data corresponds to a plurality of subcarriers. A subcarrier weighting module generates weighted subcarrier data by applying subcarrier weights to the subcarrier data corresponding to selected ones of the plurality of subcarriers. An OFDM decoder generates decoded OFDM data based on the weighted subcarrier data. | 03-05-2015 |
20150065072 | LOW VOLTAGE TRANSMITTER - A wireless communications transmitter is divided into N binary weighted communication signal processing paths including both fixed and variable gain communication signal processing chains. Specific bit sequences are used to select a combination of fixed and variable gain signal processing paths to adjust to a desired transmitter output power. Alternately, high and low power communication signal processing paths are chosen as needed with the high power communication signal processing path including an odd order harmonic notch filter. | 03-05-2015 |
20150087245 | RECEIVER FOR CARRIER AGGREGATION - A single hybrid receiver is provided for processing both single carrier and carrier aggregated (CA) communications signals where carriers are split into independent receive paths without any additional external components. The receiver receives all contiguous and non-contiguous intra-band CA and inter-band CA signals allowing for improved rejection and balanced rejection of jamming signals on either side of the two carrier signals. | 03-26-2015 |