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Noise or interference elimination

Subclass of:

455 - Telecommunications

455091000 - TRANSMITTER

Patent class list (only not empty are listed)

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Class / Patent application numberDescriptionNumber of patent applications / Date published
455114300 Predistortion (e.g., for power amplifier) 63
Entries
DocumentTitleDate
20100022206TRANSMISSION NOISE CANCELLATION - Exemplary embodiments of the disclosure are directed to down-converting an RF signal of a transmitter to baseband, filtering the down-converted signal, and generating a composite signal based on the filtered down-converted signal and a transmission based-band signal.01-28-2010
20120244824MINIMIZATION OF RMS PHASE ERROR IN A PHASE LOCKED LOOP BY DITHERING OF A FREQUENCY REFERENCE - A novel and useful apparatus for and method of minimizing the phase distortions experienced at the output of a phase locked loop (PLL) by dithering of its input frequency reference to overcome additive interference that is parasitically suffered on it. The frequency reference signal is dithered in a controlled manner using either indirect or direct coupling. The dither signal may be a single clock or is generated by switching between two or more of the existing clock signals generated, or may be produced by a dedicated pseudo-random noise generator having specific spectral properties. In indirect coupling, the dither signal is coupled through a bond wire sufficiently close in proximity to the frequency reference circuit input. This dominates the jitter inflicted onto the frequency reference signal and upconverts its spectral content to higher frequency, thus eliminating the more damaging low-frequency jitter caused by the interfering RF signal. In direct coupling, the dither signal is coupled to the reference frequency input using a network of components directly connected thereto.09-27-2012
20130040586SYSTEM AND METHOD FOR IMPROVING POWER EFFICIENCY OF A TRANSMITTER - In accordance with some embodiments of the present disclosure, a circuit comprises a balun configured to receive a radio frequency (RF) signal at a first input port and a second input port of an input coil. The balun is further configured to output the RF signal at an output coil communicatively coupled to the input coil. The circuit also comprises a supply voltage selector circuit coupled to the input coil and configured to adjust a bias voltage at the input coil according to a power level of the RF signal received at the input coil.02-14-2013
20130040587DISTORTION COMPENSATION DEVICE, DISTORTION COMPENSATION METHOD, AND RADIO TRANSMITTER - A distortion compensation device includes: a frequency-characteristic adding unit configured to add a frequency characteristic to an error signal to generate an added error signal, the error signal being a difference between an input signal input to an amplifier and an output signal output from the amplifier; a distortion-compensation-coefficient updating unit configured to update a distortion compensation coefficient for compensating for a distortion characteristic of the amplifier based on the added error signal; and a distortion compensation unit configured to perform distortion compensation on the input signal using the updated distortion compensation coefficient.02-14-2013
20090124218RF Transmitter with Heat Compensation and Method Therefor - An RF transmitter (05-14-2009
20130052971INTERFERENCE REDUCTION SYSTEMS AND METHODS - The antenna on hand held devices, such as the iPhone or iPad, can be subject to interference from other circuitry on the device. Such interference may come from high frequency switching of nearby display circuitry, such as de-multiplexors or other circuits. To address this issue, the switching rates may be slowed in certain circuits by adding resistance and/or capacitance, thus raising the RC time constant and slowing the switching times to reduce the high frequency components. Alternatively or in addition to, an EMI shield can be placed over some or all of the display driving circuitry to shield the antenna from high frequency interference.02-28-2013
20100130144TECHNIQUES FOR IMPROVING TRANSMITTER PERFORMANCE - Exemplary embodiment are directed to preserving transmitter linearity in RF transceivers while reducing RX band noise for use with low-power voltage supplies. In one aspect, a programmable attenuation element may be provided on-chip at the output of a driver amplifier, prior to a matching network. In another aspect, the programmable attenuation element may include a plurality of switchable capacitors.05-27-2010
20130065544DYNAMIC TRANSMITTER CALIBRATION - A method includes generating an indicator of interference introduced by a transmitter into a spectrum of an output transmit signal outside a target channel of the transmitter. The indicator is generated based on the output transmit signal. The method includes adjusting a power level of the output transmit signal based on the indicator and a predetermined interference indicator level. The indicator may indicate a carrier-to-interference (C/I) ratio of the output transmit signal, and the adjusting comprises setting the power level of the output transmit signal to a maximum power level that maintains the C/I ratio of the output transmit signal above the predetermined interference indicator level. The output transmit signal may be based on a radio-frequency output of a power amplifier of the transmitter prior to transmission over a channel and the generating comprises generating a baseband version of the output transmit signal.03-14-2013
20090011724A RADIO TELECOMMUNICATION TERMINAL AND A METHOD OF DECREASING PERTURBATIONS WITHIN THIS TERMINAL - The radio telecommunication terminal (01-08-2009
20110300817APPARATUS AND METHOD FOR REMOVING TRANSMISSION LEAKAGE SIGNAL - An apparatus and method for removing a transmission leakage signal from a radio frequency identification (RFID) reader are provided. The apparatus includes a removing unit having a device of a large impedance and a phase shifter capable of a wide range phase change with respect to a leakage signal, thereby optimally removing the transmission leakage signal irrespective of a change in the frequency characteristics and a change in the length of a cable.12-08-2011
20080242244SYSTEM HAVING A FILTER - A system having a filter is disclosed. One embodiment includes at least two polyphase filter branches, each of the polyphase filter branches including a respective recursive allpass filter, wherein the filter approximates a linear filter.10-02-2008
20100120383DIFFERENTIAL OUTPUT CIRCUIT AND COMMUNICATION DEVICE - A differential includes first and second current mirror circuits that provide the gates of slave transistors with gate voltages of master transistors via a voltage follower where a slew rate at a rise time is equal to a slew rate at a fall time. Thus, when the master current is increased or decreased, an incremental change in slave current and a decremental change in slave current are symmetrical with each other. The use of such current mirrors in a differential manner leads to no generation of common mode noise even in these changes.05-13-2010
20100120382Systems and Methods for Dampening TDMA Interference - Systems and methods are disclosed which relate to mitigating the detrimental effects of interference to electronic devices from mobile telephones utilizing any form of time-domain multiplexing technology. A wireless transmitter inside the mobile telephone broadcasts a warning transmission which can be received by affected devices. Once the warning transmission is received by an affected device, the device activates a blanking circuit comprising an actuator and a switch or switches. The switches open for the duration of the interference so that the user does not receive undesired output such as: noise through a speaker, noise through a microphone, or other interference with electrical signals.05-13-2010
20090264088METHOD FOR MITIGATING INTERFERENCE - A method for mitigating interference is provided. First, a received signal having a training sequence is received from a transmitter. Then, a Signal-to-Interference-plus-Noise Ratio (SINR) of the training sequence in the received signal is calculated, and whether a co-channel interference signal exists in the received signal is determined according to the SINR. The signal power corresponding to each time index in the received signal is calculated to detect a beginning time point and an ending time point of the co-channel interference signal. Finally, when the co-channel interference signal in the received signal is detected, the time when an interference cancellation filter is turned on is determined by the beginning time point and the ending time point.10-22-2009
20090264087Apparatus and method for beamforming considering interference amount in broadband wireless communication system - An apparatus and method for beamforming in a broadband wireless communication are provided. The apparatus includes a first calculator for determining a degradation factor to indicate a degradation degree of a target signal due to interference cancellation by using a target channel matrix and at least one interfering channel matrix, a second calculator for determining a new noise power value to be used to calculate a beamforming vector if the degradation factor is greater than or equal to a threshold, and for determining the beamforming vector by using the new noise power value, and a beamformer for performing beamforming on a signal transmitted/received with a target Mobile Station (MS) by using the beamforming vector.10-22-2009
20080207147Radio transmitter front-end with amplitude and phase correction and methods for use therewith - A radio transmitter front-end for use in a voice data and RF integrated circuit (IC) includes a phase correction module that produces a phase adjusted signal in response to a phase modulated signal and at least one phase correction signal. An amplitude correction module produces an amplitude adjusted signal in response to an amplitude modulating signal and an amplitude correction signal. An amplifier amplifies the phase adjusted signal and amplitude modulates the phase adjusted signal, based on the amplitude adjusted signal, to produce a polar coordinate transmit signal. A correction generation module generates the at least one phase correction signal and the amplitude correction signal, based on the polar coordinate transmit signal and the phase adjusted signal.08-28-2008
20080233901Radio Communication Apparatus and Peak Suppression Method - A radio communication apparatus enabling reduction in peak-to-average power ratio without decreasing the transmission efficiency. In this apparatus, buffer section 09-25-2008
20080274707Method and Apparatus to Minimize Interference Among Co-Located Multiple Wireless Devices - Disclosed is a method and apparatus for managing transmit requests among a plurality of co-located transmitting devices each associated with a wireless transmitting protocol. The method comprises the steps of determining the cost associated with each of the transmit requests, wherein the cost is associated with the cost of granting the request and the cost of rejecting the request, granting the request associated with the lowest cost, and rejecting all other requests. In another aspect of the invention, the method comprises the step of determining whether the lowest cost is acceptable and rejecting the request associated with the lowest cost when the lowest cost is unacceptable.11-06-2008
20130217349Post Filter for Spectral Domain Echo Cancellers to Handle Non-Linear Echo Components - The present document discloses a method and system for improving echo cancellation in the presence of non-linear distortions. A circuit attenuates a transmit signal in one or more spectral bands based on a receive signal. The distorted echo comprised within the transmit signal results from distortions incurred by the receive signal when being rendered by an electronic device. The circuit compares energy values of the receive signal in multiple spectral bands with multiple corresponding spectral band dependent distortion thresholds and determines that for a first spectral band from multiple spectral bands. A first energy value from multiple energy values exceeding a first distortion threshold from multiple distortion thresholds attenuates the transmit signal in one or more spectral bands at higher frequencies than the first spectral band with corresponding spectral band dependent attenuation factors.08-22-2013
20090298446DISTORTION COMPENSATING APPARATUS, WIRELESS COMMUNICATING APPARATUS, AND DISTORTION COMPENSATING METHOD - A distortion compensating apparatus includes following units. An information measuring unit measures a distortion component and an electric power component based on a radiation signal. A compensation coefficient calculating unit calculates a compensation coefficient based on the distortion component and the electric power component. A signal transmitting unit outputs a signal corrected by the compensation coefficient as a transmission signal. A signal converting unit converts the transmission signal into a high frequency signal. An amplitude separating unit amplifies the high frequency signal and separates a portion thereof as a signal to be fed back. A feeding-back unit processes the portion and outputs the result as a feedback signal to the information measuring unit. An electric power information extracting unit outputs a portion of the high frequency signal as the radiation signal, extracts electric power information from the radiation signal, and directly outputs the electric power information to the information measuring unit.12-03-2009
20090081970INTERFERENCE MANAGEMENT EMPLOYING FRACTIONAL FREQUENCY REUSE - Interference that occurs during wireless communication may be managed through the use of fractional reuse and other techniques. In some aspects fractional reuse may relate to HARQ interlaces, portions of a timeslot, frequency spectrum, and spreading codes. Interference may be managed through the use of a transmit power profile and/or an attenuation profile. Interference also may be managed through the use of power management-related techniques.03-26-2009
20090088092INTERFERENCE AVOIDANCE - A method of shaping signals intended for transmission via at least one antenna, each signal having a respective frequency spectrum and being for transmission via a respective antenna, comprises selecting at least one interference-reducing signal, each interference-reducing signal being such as to modify the signal frequency spectrum for the antenna or a respective one of the antennas to include a respective frequency notch at an interference band, and modifying the frequency spectra with the selected interference-reducing signal or signals, wherein the selection is subject to a constraint on at least one characteristic of the spectra as modified04-02-2009
20090023404Controlling a Receiver - A receiver 01-22-2009
20090023403SYSTEM AND METHOD FOR CONTROLLING INTERMODULATION INTERFERENCE - In one embodiment, a method of controlling intermodulation (IM) interference is provided. The method comprises determining if an IM product spectrum overlaps the spectrum of an assigned receive frequency and determining when transmissions from at least two transmitters are to overlap in time. If the IM product spectrum overlaps the assigned receive frequency spectrum, it is determined if a signal is being propagated on the receive frequency when the transmissions from the at least two transmitters are to overlap in time. If a signal is not being propagated on the receive frequency, the at least two transmitters are allowed to transmit the overlapping transmissions; and if a signal is being propagated on the receive frequency, control steps are initiated to reduce the effects of IM interference01-22-2009
20100197249ADJUSTABLE TRANSMISSION FILTER - An adjustable filter is responsive to a control signal to change a frequency response of the adjustable filter based on at least one of a geographic location, frequency spectrum information, and a status of a secondary internal radio. The control signal may shift a center of the pass band from a first center frequency to a second center frequency and/or change a pass band bandwidth from a first bandwidth to a second bandwidth. A transmitter includes an adjustable filter responsive to a control signal and controller configured to select a frequency response of the adjustable filter by generating the control signal based on a geographical location. In one aspect, the geographical location indicates a region of operation of the receiver and the frequency response is selected in accordance with the region.08-05-2010
20110028108Method and apparatus to provide low cost transmit beamforming for network devices - Techniques and structures for use in generating an approximated beamforming matrix in a MIMO based system are disclosed. The techniques and structures may be used to allow closed loop MIMO beamforming to be performed within a device that does not include singular value decomposition (SVD) circuitry.02-03-2011
20110250857Interference Avoidance in White Space Communication Systems - Mobile communication system equipment avoids interfering with another transmitter's operation. Sensing information indicating whether the other transmitter's signal has been detected is received from remote sensors, wherein each of the remote sensors is situated at a respective one of two or more sensor locations. The sensing information and information about the sensor locations is used to ascertain one or more exclusion boundaries needed to avoid interfering with the other transmitter's use of the spectral resource. Beamforming parameters are ascertained that will enable the main node to transmit within one or more predefined geographical areas except for any portion of a predefined area located on a far side of the one or more exclusion boundaries. Two or more adjusted signals are produced as a function of the beamforming parameters and one or more signals to be transmitted. The adjusted signals are transmitted from respective ones of two or more antennas.10-13-2011
20110076968COMMUNICATION DEVICE WITH REDUCED NOISE SPEECH CODING - A communication device includes memory, an input interface, a processing module, and a transmitter. The processing module receives a digital signal from the input interface, wherein the digital signal includes a desired digital signal component and an undesired digital signal component. The processing module identifies one of a plurality of codebooks based on the undesired digital signal component. The processing module then identifies a codebook entry from the one of the plurality of codebooks based on the desired digital signal component to produce a selected codebook entry. The processing module then generates a coded signal based on the selected codebook entry, wherein the coded signal includes a substantially unattenuated representation of the desired digital signal component and an attenuated representation of the undesired digital signal component. The transmitter converts the coded signal into an outbound signal in accordance with a signaling protocol and transmits it.03-31-2011
20110151808System And Method For Power Control For A Surface Acoustic Wave (SAW) Filter-Less Transmitter - A power control system includes a transmitter having a plurality of gain-adjustable elements, a switchable attenuator located at an output of the transmitter, a gain-adjustable power amplifier coupled to the attenuator, and a power control element responsive to a power target signal, the power control element configured to calculate and apply a gain control signal to the plurality of gain-adjustable elements in the transmitter, to the switchable attenuator, and to the gain-adjustable power amplifier so that a signal to noise ratio (SNR) at the output of the transmitter remains substantially constant over a range of output power.06-23-2011
20120202440DISTORTION COMPENSATION DEVICE, TRANSMITTER, AND DISTORTION COMPENSATION METHOD - A distortion compensation device includes a distortion compensator that predistorts an input signal based on delay signals and distortion compensation coefficients corresponding to the respective delay signals obtained by applying different amounts of delay to the input signal, a calculator that calculates an error signal based on the predistorted input signal and an output signal from an amplifier that amplifies the predistorted input signal, a calculator that calculates prospective distortion compensation coefficients for updating the distortion compensation coefficients, based on the error signal, a saturation processor that performs saturation processing for bringing, when the prospective distortion compensation coefficients do not fall into a preset range, the prospective distortion compensation coefficients into the preset range, and a controller that controls the updating of the distortion compensation coefficients based on pieces of coefficient saturation information indicating whether the saturation processing is performed on the prospective distortion compensation coefficients.08-09-2012
20090149140POWER CONTROL UTILIZING MULTIPLE RATE INTERFERENCE INDICATIONS - Systems and methodologies are described that facilitate mitigation of interference in a wireless communication environment. Terminals can utilize interference information provided by neighboring sectors to adjust transmit power and reduce interference. Access points can provide two sets or types of interference information. The first type can be transmitted over a large coverage area, requiring significant overhead and limiting the transmission rate. Access points can also provide a second set or type of interference information directed at smaller coverage area, such as an area proximate to the edge of the supported sector. This second type of interference information can be utilized by terminals that include the access point within their active set. The second set of interference information can be provided at a higher rate than the first set due to decreased overhead requirements. Terminals can utilize both sets of interference information to adjust transmit power.06-11-2009
20100184391SWEPT NOTCH ULTRA WIDE BAND (UWB) TRANSMITTER - A UWB or other transmitter reduces interference to a narrow-band victim receiver on a periodic basis by means of a frequency swept notch. The notch may be created using active interference cancellation signal processing or simple deletion of sub-carriers. Details are given of both methods.07-22-2010
20110053529SEMICONDUCTOR INTEGRATED CIRCUIT FOR COMMUNICATION - The present invention provides a semiconductor integrated circuit for communication (RF IC) realizing high yield without deteriorating a carrier leak characteristic even when a modulation circuit is formed by using cheep parts with large variations. In a semiconductor integrated circuit (RF IC) including: an input circuit constructed by a differential amplifier circuit and a level shifter, which is provided on the ante stage of a mixer of a differential circuit called a Gilbert Cell; and a modulation circuit that performs modulation by adding an I/Q signal and a carrier wave signal, a calibration circuit for canceling a DC offset in an output of the input circuit is provided.03-03-2011
20110053528METHOD AND SYSTEM FOR DETECTING NON-LINEAR DEVICES - To assist with the detection of unfiltered device(s), a system observes how the received noise changes between two links as the transmit signal is changed. Harmful unfiltered nonlinear devices will generate significant noise that depends on the transmitted signals; therefore, this additional noise can be quantified to some extent by comparing the observed noise for two different transmit signals. The total noise can be determined from the SNR if the received signal is known. The received signal may be read directly in some non-standard systems, or it may be determined from the known transmit signal and channel attenuation, which is sometimes the case in standard-compliant links, but often with a relatively large error. To circumvent this problem, certain embodiments of this invention only consider the change in noise between two links with the same channel attenuation. This differential comparison makes it unnecessary to accurately know the channel attenuation.03-03-2011
20110028107SPECTRUM SENSING NETWORK - In accordance with various embodiments methods, systems and devices are generally described for assigning a reputation value to a cognitive device in a communications system. Some of the described methods may include one or more of generating reputation value information, assigning a reputation value associated with the cognitive device, based on the reputation value information, and transmitting the reputation value associated with the cognitive device, to the cognitive radio. In addition, some other described methods may include one or more of associating a reputation value with the cognitive device, receiving cognitive information from the cognitive device, and performing a cognitive task using the cognitive information based on the reputation value exceeding a threshold value.02-03-2011
20110136448UPLINK POWER CONTROL SCHEME - An uplink power control technique may include a simplified maximum sector throughput (SMST) and a generalized maximum sector throughput (GMST). The SMST and GMST techniques may be used to determine a maximum sector throughput and cell-edge throughput to enhance the overall efficiency of the communication system. The uplink power control technique may determine the optimal uplink power value without collecting interference over thermal noise and without computing the individual channel losses in each neighboring sector.06-09-2011
20110189964METHOD AND APPARATUS FOR PROVIDING IMPEDANCE MATCHING FOR HIGH-FREQUENCY SIGNAL TRANSMITTER - In accordance with another representative embodiment, a high-frequency signal transmitter a power amplifier configured to supply a high-frequency signal; an antenna configured to transmit the high-frequency signal; a transmission line configured to transfer the high-frequency signal from the power amplifier to the antenna; and an impedance matching circuit connected to the transmission line. The high-frequency signal transmitter also comprises a mismatch detector. The mismatch detector is configured to designate a comparatively poor linearity region and a comparatively good linearity region by dividing a Smith chart into the two regions based on Adjacent Channel Power Ratio (ACPR) contours drawn on the Smith chart at a point on the transmission line where the impedance matching circuit is connected, to measure a time-dependent reflection coefficient of the high-frequency signal transmitter in terms of a phase and a magnitude, to determine whether the reflection coefficient is located in the comparatively poor linearity region or the comparatively good linearity region, and based on a result of the determination, to improve the linearity of the high-frequency signal transmitter.08-04-2011
20100022207TRANSMITTER - To provide a transmitter wherein even in a case of sharing a detector circuit between or among a plurality of transmitting circuits, a high degree of detection accuracy can be achieved without increasing the signal power supplied to the detector circuit. In a transmitter including a detector circuit 01-28-2010
20090011725RADIO RECEIVER AND RADIO TRANSMITTER - A radio receiver includes an aerial wire that receives a radio signal in which a transmission signal is superimposed on a carrier, a voltage-controlled oscillator that oscillates a local oscillation signal, a frequency multiplier, a demodulation circuit that demodulates the transmission signal on the basis of the radio signal and the local oscillation signal, and an oscillation frequency control circuit that repeatedly sweeps the frequency of the local oscillation signal over a frequency bandwidth that is equal to or greater than the width of a frequency drift in a carrier frequency from the aerial wire or over a frequency bandwidth that is equal to or greater than the width of a frequency drift in the local oscillation signal.01-08-2009
20090081969DIGITAL FM RADIO TRANSMITTER - A digital FM transmitter has a digital controlled oscillator for generating a modulated RF carrier. A digital signal processor receives digital input samples and generates a modulating signal for input to the digital controlled oscillator. A bandpass filter for filters frequency components of the modulated carrier outside a predetermined frequency band and supplies the filtered modulated RF carrier to an antenna.03-26-2009
20090163154Method For Compensating Signal Distortions in Composite Amplifiers - A method for compensating signal distortions in multiple transmitting branches (06-25-2009
20080207146High Dynamic Range Receiver - The invention relates to an adjustment method, especially for adjusting optical or fibre optical components. Said method involves locally heating, in a defined manner, at least one first partial region of an adjustment region (08-28-2008
20090111398Transmitter and transmission method - There is provided an apparatus, having a first local oscillator generate a first oscillation signal, a first mixer generating a transmit signal by mixing an input signal and the first oscillation signal, an observation receiver receiving a portion of the transmit signal, and applying, in a first operation mode of the apparatus, the received portion of the transmit signal such that a transmit signal component on a frequency of the first oscillation signal falls into a band-pass frequency of the observation receiver, and shift, in a second operation mode of the apparatus, the received portion of the transmit signal such that an oscillation leakage signal component of the first oscillation signal falls into the band-pass frequency of the observation receiver; and a compensation unit generating a compensation signal based on the band-pass signal of the observation receiver for compensation of the input signal.04-30-2009
20120171974Noise Suppression - The present invention relates to a method of suppressing noise in a communication device. The idea consists in forwarding to a noise suppression module some information regarding the radio transmission in terms of radio activity and/or in terms of radio transmission power. The module then advantageously uses this information to suppress radio path noise.07-05-2012
20120071116MU MIMO SUPPORT WITH HIGHLY DIRECTIONAL ANTENNAS - In various embodiments, a network controller in a multi-user multiple input multiple output (MU MIMO) network may perform training for directional communications with multiple mobile devices. It may organize the mobile devices into different groups, with all the mobile devices in a single group able to communicate simultaneously with the network controller without excessive interference from each other. Various techniques may be used for such training and grouping.03-22-2012
20100173596FEED FORWARD NOISE REDUCTION IN A TRANSMITTER - A circuit (07-08-2010
20120315865MICROWAVE TRANSMISSION METHOD, APPARATUS, AND SYSTEM USING CCDP AND XPIC - Embodiments of the present invention disclose a microwave transmission method, apparatus, and system using CCDP and XPIC, and relate to the field of mobile communication technologies. The microwave transmission method includes: sending two channels of service that are corresponding to the same frequency and have different polarization directions, where the two channels of service are paired into one logical group; and when receiving, through a feedback channel, a failure signal sent by another end, closing sending of a channel of service that is indicated by the failure signal. In the embodiments of the present invention, after the failure signal sent by the another end is received, the sending of a channel of the service that is indicated by the failure signal is closed, so that no interference is caused to another channel of service, thus ensuring that another channel of service is received correctly.12-13-2012
20090068965Method, Apparatus and System for an Omni Digital Package for Reducing Interference - A system for an omni digital package for reducing interference may include a passive combiner and a transmit signal canceller. The passive combiner may be configured to combine at least two input frequencies to produce a combined signal. The transmit signal canceller may be configured to determine an interference frequency based on a combination of the at least two input frequencies. The transmit signal canceller may include a tap weight determiner configured to determine a weighting coefficient associated with the interference frequency, and a cancellation function configured to perform a cancellation operation to at least partially cancel the interference frequency from the combined signal based on the weighting coefficient.03-12-2009
20120322395REJECTION OF RF INTERFERERS AND NOISE IN A WIRELESS COMMUNICATIONS TRANSCEIVER - The invention provides a radio receiver or transceiver having one or more low noise amplifiers corresponding to one or more antenna inputs wherein one or more outputs of the one or more low noise amplifiers is/are combined at a single output current summing node, a tunable, shunt notch filter is coupled or connected to the summed output node that allows for the attenuation of a Tx blocker or interferer, an external blocker or interferer or an internal on-chip interferer.12-20-2012
20100233973ANTENNA BEAM FORMING SYSTEMS, METHODS AND DEVICES USING PHASE ADJUSTED LEAST SQUARES BEAM FORMING - Methods of operating a transceiver including an antenna having a plurality of antenna feed elements include providing a plurality of gain constraint values associated with respective ones of the plurality of geographic constraint points within a geographic region, selecting initial phase constraint values associated with respective ones of the gain constraint values, generating antenna feed element weights based on the gain constraint values and based on the initial phase constraint values, and determining system response values in response to the antenna feed element weights. Phases of the system response values are compared to the initial phase constraint values, and an antenna beam is formed from the antenna to the geographic region using the antenna feed element weights in response to the comparison of the phases of the system response values to the initial phase constraint values. Related systems and devices are also disclosed.09-16-2010
20120100819MOBILE WIRELESS COMMUNICATIONS DEVICE WITH REDUCED HARMONICS RESULTING FROM METAL SHIELD COUPLING - A mobile wireless communications device includes a housing, antenna, and circuit board carried by the housing and having radio frequency (RF) circuitry operative with the antenna for receiving and transmitting RF signals through the antenna. A power amplifier is connected within a transmission line for amplifying RF signals to be transmitted over the transmission line to the antenna. An antenna switch is connected to the antenna and RF circuitry. An RF shield surrounds the power amplifier and antenna switch and isolates the power amplifier and antenna switch from the antenna and RF circuitry. A low pass filter is connected to the power amplifier and antenna switch for reducing any RF coupling of voltage standing waves of upper harmonic frequencies from the power amplifier into the antenna switch through the RF shield while maintaining transmission of signals through the transmission line at a desired fundamental frequency.04-26-2012
20130115899PEAK SUPPRESSION ON MULTICARRIER - A ceiling value can be established (05-09-2013
20130149976Method And System For A Linearized Transmitter Including A Power Amplifier - Disclosed are various embodiments for transmitting radio frequency signals. A radio frequency transmitter may be configured to generate an analog signal comprising an in-phase component and a quadrature-phase component. The in-phase component and the quadrature-phase component of the analog signal may be provided to multiple radio frequency processing chains. One of the radio frequency processing chains may generate an output radio frequency signal based on the in-phase component and the quadrature-phase component.06-13-2013

Patent applications in class Noise or interference elimination

Patent applications in all subclasses Noise or interference elimination