Patent application number | Description | Published |
20080270082 | Low-power and low-cost adaptive self-linearization system with fast convergence - A signal processing method includes inputting a digital signal, providing a plurality of coefficients; and determining an output. The output is approximately equal to an aggregate of a plurality of linear reference components, and each of the linear reference components is approximately equal to an aggregate of a corresponding set of digital signal samples that is scaled by the plurality of coefficients. | 10-30-2008 |
20080288199 | Distortion cancellation using adaptive linearization - A method of signal processing includes receiving a distorted signal comprising a distorted component and an undistorted component, the distorted component being at least in part attributed to an exogenous signal, and performing linearization, based at least in part on the distorted signal and information associated with the exogenous signal, to obtain a corrected signal that is substantially similar to the undistorted component. An adaptive distortion reduction system includes an input interface configured to receive a distorted signal comprising a distorted component and an undistorted component, the distorted component being at least in part attributed to an exogenous signal; and an adaptive distortion reduction module coupled to the input interface, configured to perform linearization based at least in part on the distorted signal and information associated with the exogenous signal, to obtain a corrected signal that is substantially similar to the undistorted component. | 11-20-2008 |
20080291066 | Composite analog to digital receiver with adaptive self-linearization - A distortion correcting analog to digital converter (ADC) system includes a plurality of ADCs configured to convert an analog signal to a plurality of digital ADC outputs, wherein the plurality of ADCs are configured to generate a composite signal based on the plurality of ADC outputs, there is an offset between a first one of the plurality of ADC outputs and a second one of the plurality of ADC outputs, the offset causing distortion in the composite signal. The system further includes an adaptive self-linearizer configured to receive the composite signal, and to perform self-linearization based on the composite signal to correct for the distortion in the composite signal. | 11-27-2008 |
20090021304 | Model based distortion reduction for power amplifiers - A method of processing a signal is disclosed. The method comprises generating a digital signal, converting the digital signal to an analog signal, and generating an amplified analog signal having distortions. The method further comprises converting the amplified analog signal to a feedback digital signal at a sample rate and updating a model of the distortions based on the feedback digital signal. | 01-22-2009 |
20090029664 | Crest factor reduction - A device for generating a crest factor reduced signal is disclosed. The device comprises an interface for receiving an input signal; a peak identifier for identifying one or more peak regions of the input signal; a squelch level determiner for determining a reduction of the input signal near the one or more peak regions; a squelcher for reducing the one or more peak regions of the input signal as indicated by the squelch level determiner; and an interface for outputting a crest factor reduced signal. The crest factor reduced signal has a reduced dynamic range due to the reduction of the one or more peak regions of the input signal. The crest factor reduced signal also has been filtered to reduce undesired frequency components by: calculating a difference between a squelched signal from the squelcher and the input signal, band-pass filtering the difference to generate a result, and summing the result with the input signal that has been delayed. | 01-29-2009 |
20090054999 | Nonelinear system observation and control - An observation system configured to observe one or more initially unknown state variables of an observed system includes an input interface configured to receive a system input, and a processing module coupled to the input interface. The processing module is configured to determine the one or more initially unknown state variables, and the determination is based at least in part on the system input, a plurality of known state variables, and a time varying mode vector that is time dependent. | 02-26-2009 |
20090094304 | System and method for adaptive nonlinear filtering - An adaptive nonlinear filtering system includes an adaptive filter module that is configured to generate relative location information pertaining to a relative location of an input signal within an input range; determine an input dependent filter parameter based at least in part on the relative location information; generate an output signal based at least in part on the input dependent filter parameter; and feed back a feedback signal that is generated based at least in part on the output signal and a target signal. | 04-09-2009 |
20100141490 | Model based distortion reduction for power amplifiers - A method of processing a signal is disclosed. The method comprises generating a digital signal, converting the digital signal to an analog signal, and generating an amplified analog signal having distortions. The method further comprises converting the amplified analog signal to a feedback digital signal at a sample rate and updating a model of the distortions based on the feedback digital signal. | 06-10-2010 |
20110314074 | LOW POWER AND LOW COMPLEXITY ADAPTIVE SELF-LINEARIZATION - A digital signal processing system comprising: an input terminal to receive an input signal that includes a distorted component and an undistorted component, the input signal having a sampling rate of R; and an adaptive self-linearization module coupled to the input terminal, to perform self-linearization based at least in part on the input signal to obtain an output signal that is substantially undistorted, wherein: the adaptive self-linearization module is to generate a replica distortion signal that is substantially similar to the distorted component, the generation being based at least in part on a target component having a sampling rate of R/L, L being an integer greater than 1; the adaptive self-linearization module includes a first digital signal processor (DSP) that is adapted to obtain a filter transfer function that approximates a system distortion transfer function, and a second DSP that is configured using configuration parameters of the first DSP. | 12-22-2011 |
20120029881 | DISTORTION CANCELLATION USING ADAPTIVE LINEARIZATION - An adaptive distortion reduction system comprising: an input interface to receive a distorted signal comprising a distorted component and an undistorted component, the distorted component being at least in part attributed to an exogenous signal; and an adaptive distortion reduction module coupled to the input interface, to perform linearization based at least in part on the distorted signal and information associated with the exogenous signal, to obtain a corrected signal that is substantially similar to the undistorted component; wherein the adaptive self-linearization module includes: a first digital signal processor (DSP) that is adapted to obtain a filter transfer function that approximates a transfer function to be corrected; and a second DSP that is configured using configuration parameters of the first DSP. | 02-02-2012 |
20120046925 | MODEL BASED DISTORTION REDUCTION FOR POWER AMPLIFIERS - A method of processing a signal is disclosed. The method comprises generating a digital signal, converting the digital signal to an analog signal, and generating an amplified analog signal having distortions. The method further comprises converting the amplified analog signal to a feedback digital signal at a sample rate and updating a model of the distortions based on the feedback digital signal. | 02-23-2012 |
20130089169 | Low-Power and Low-Cost Adaptive Self-Linearization System with Fast Convergence - A signal processing method includes inputting a digital signal, providing a plurality of coefficients; and determining an output. The output is approximately equal to an aggregate of a plurality of linear reference components, and each of the linear reference components is approximately equal to an aggregate of a corresponding set of digital signal samples that is scaled by the plurality of coefficients. | 04-11-2013 |