Abstract: The present invention relates to a method and arrangement for reducing interference in a cellular communication network. A radio base station of the network is configured to serve at least a first cell, where interference is reduced by selecting a link adaptation scheme for a UE in the first cell, The arrangement comprises means for receiving measurements on estimated channel quality, means for estimating channel quality for a future transmission by adjusting the received measurements on estimated channel quality based on knowledge of future UE scheduling in at least the first cell, and means for selecting the link adaptation scheme comprising a transmit power level based on the estimated channel quality for the future transmission.

Abstract: A mixing stage includes a first modulation stage that receives an input signal from a first common node of the mixing stage, a first local oscillator input that receives a local oscillator signal, and a first modulation signal output adapted to provide a first modulated signal. A second modulation stage of the mixing stage includes a second input that receives a phase inverted representation of the input signal from a second common node of the mixing stage, a second local oscillator input that receives the local oscillator signal, and a second modulation signal output adapted to provide a second modulated signal. A current generation circuit provides a supply current to the first common node and to the second common node. A current control circuit is adapted to superimpose an offset current to the current of at least one node of the first common node and the second common node.

Abstract: The embodiments of the present invention provide a predistortion device, method for predistortion and transmitter/receiver system. The predistortion device comprises a predistortion unit, and the predistortion device further comprises: a signal acquiring unit to process the output signals of a transmitting circuit to obtain distorted signals; a signal coupling unit to couple the distorted signals acquired by the signal acquiring unit to the receiving signals inputted to a receiving circuit; and a signal processing unit to decouple the output signals of the receiving circuit to acquire the distorted signals and the receiving signals. With the embodiments of the present invention, an analog receiving circuit may be reused in a half duplexing system and a full duplexing system, and the requirement on the analog receiving circuit is lowered, thereby reducing the cost.

Abstract: In one embodiment, an amplifier system has a tap, a delay filter, a linearized amplifier, and a hybrid combiner. The tapped portion of an input signal is amplified by the amplifier, the untapped portion of the input signal is delayed by the delay filter, and the combiner combines the resulting amplified, tapped portion and the delayed, untapped portion to generate an amplified output signal. By re-combining the delayed, untapped portion of the input signal with the amplified, tapped portion, the power of the untapped portion is not lost, and the amplifier does not have to compensate for all of the distortion that would otherwise be associated with the total output power level. Such an amplifier system is applicable, for example, in upgrading an existing GSM cell site to support both GSM communications as well as UMTS communications without degrading GSM operations.

Abstract: Systems and methods are disclosed relating to transmission of communications via high frequency antenna systems employing high-temperature superconductor filters and/or amplifiers. In certain embodiments, a comb linear amplifier combiner may be modified with, for example, cryogenically cooled and/or high-temperature superconductor components, such as matching units of bandpass filters. A computer control unit may be coupled to the transmission circuit to control operation of one or more of the low-power transmitters, filters, and/or amplifiers.

Abstract: 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.

Abstract: Certain embodiments provide a Femtocell base station arranged to receive interference notifications from another Femtocell base station and to send an interference remedial command to the other Femtocell base station and/or to one or more further Femtocell base stations.

Abstract: A composite wireless device including a WLAN device and a BT device. The composite wireless device includes a wireless-channel control unit that determines usable FH channels that can be used for frequency hopping of the BT device, based on communication quality information of the WLAN channel, and notifies the BT device of the usable frequency bands, and a BT-communication control unit that acquires communication quality information of an extended frequency band, which is a frequency band other than the usable frequency bands, as extended communication quality information. The wireless-channel control unit adds the FH channels in the WLAN channel, which are determined as being unused based on the extended communication quality information, as the usable FH channels.

Abstract: A mixer for a transmitter includes a voltage converter to convert a baseband voltage to a baseband current. A mixer component mixes the baseband current with a local oscillator frequency. An output of the mixer component includes a radio frequency signal and a higher order radio frequency signal. A coupler sends the radio frequency signal and the higher order radio frequency signal to a differential output. A filter is integrated into the coupler to filter the higher order radio frequency signal before being output by the differential output.

Abstract: A communications device is disclosed that implements a phase-locked-loop to multiply a clock signal provided to a power management unit (PMU) by a variable integer value. Multiplying the PMU clock signal provides a second clock signal where the second clock signal is characterized by a fundamental component with one or more harmonics of the fundamental component that differ from the fundamental component and the one or more harmonics of the PMU clock signal. The fundamental component with one or more harmonics of the second clock signal does not occupy the same communication channel as the transmission communication signal of the communications device. Thus, minimizing the degradation of the transmission communication signal.

Abstract: Aspects of the present disclosure relate to determining the location and/or density of vias that form part of an RF isolation structure of a packaged module and the resulting RF isolation structures. From electromagnetic interference (EMI) data, locations of where via density can be increased and/or decreased without significantly degrading the EMI performance of the RF isolation structure can be identified. In certain embodiments, one or more vias can be added and/or removed from a selected area of the packaged module based on the EMI data.

Abstract: Near-end equipment for a communication channel with far-end equipment. The near-end equipment includes at least one loudspeaker, at least two microphones, a beamformer, and an echo canceller. The communication channel may be in one of a number of communication states including Near-End Only state, Far-End Only state, and Double-Talk state. In one embodiment, when the echo canceller determines that the communication channel is in either the Far-End Only state or the Double-Talk state, the beamformer is configured to generate a nearfield beampattern signal that directs a null towards a loudspeaker. When the echo canceller detects the Near-End Only state, the beamformer is configured to generate a farfield beampattern signal that optimizes reception of acoustic signals from the near-end audio source. Using different beamformer processing for different communication states allows echo cancellation processing to be more successful at reducing echo in the signal transmitted to the far-end equipment.

Abstract: A method and apparatus for updating equalization coefficients of an adaptive pre-equalizer of a network element are provided. The method includes monitoring a communications channel to measure distortion of a communications signal received from the network element and detecting whether a transient impairment is present in the communication signal. When a transient impairment is not detected to be present, a pre-equalization coefficient update is transmitted to the network element. However, when a transient impairment is detected to be present, at least selected ones of the pre-equalization coefficients are scaled before the update is transmitted to the network element or the update is withheld from being transmitted to the network element. An apparatus is also disclosed.

Abstract: A signal amplification apparatus includes a first modulator configured to receive an envelope signal, use a predetermined reference level to separate the received envelope signal into a first period and a second period, digitally modulate a signal of the second period to output the digitally modulated signal to a first output terminal, and output a signal of the first period to a second output terminal. Further, the signal amplification apparatus includes a second modulator configured to mix the digital modulated signal input through the first output terminal with a phase modulated carrier signal; an envelope modulator configured to output the signal of the first period as a power supply signal; and a power amplifier configured to amplify the mixed signal output by the second modulator to output the amplified signal.

Abstract: In one embodiment, a wireless base station, receives a random access preamble from a wireless device that is not authorized to utilize the wireless base station; completes a random access procedure with the wireless device; receives an interference stress message from the wireless device, the interference stress message indicating that the wireless device suffers interference from the wireless base station; and reduces interference for the wireless device.

Abstract: A method for detecting an ingress of a short wave radio signal in a power line communication system which determines a strength of a common mode signal at a frequency of the power line communication system during a time period when no communication in the power line communication system at this frequency takes place and an ingress is detected if the strength of the common mode signal is above a determined threshold. A corresponding power line communication modem can implement such a method.

Abstract: An antenna power coupler having a variable coupling factor is disclosed. In an exemplary embodiment, an apparatus includes a coupler configured to generate a power detection signal based on transmit signal power associated with a plurality of transmission technologies and a variable attenuator configured to apply a selected attenuation factor to the power detection signal to generate an adjusted power detection signal, the selected attenuation factor associated with a selected transmission technology.

Abstract: A method includes, in a mobile communication terminal, receiving from at least first and second base stations, which cooperate in a coordinated transmission scheme, signals that are transmitted over respective first and second communication channels. Respective channel measures are calculated for the communication channels based on the received signals. First and second feedback data, which are indicative of the respective channel measures of the first and second communication channels, are formulated such that the first feedback data has a first data size and the second feedback data has a second data size, different from the first data size. The first and second feedback data are transmitted from the mobile communication terminal to at least one of the base stations.

Abstract: A method and an apparatus for modifying a complex-valued signal are described, the complex-valued signal representing a first symbol and a second symbol. A signal trajectory of the complex-valued signal between the first and second symbols is determined, and, if the signal trajectory passes nearby the constellation origin, the signal trajectory is altered to run closer to the constellation origin.

Abstract: A method for avoiding mutual interference when heterogeneous communication modules such as LTE, wireless LAN, Bluetooth, and GPS coexist in a terminal in a wireless communication system is provided. The terminal may reduce mutual interference when a plurality of communication modules simultaneously operate to efficiently communicate therewith.

Abstract: Various methods of mitigating RF interference with one or more critical care medical devices is provided, wherein a predetermined threshold energy acceleration value is associated with the one or more critical care medical devices that, if exceeded, will cause RF interference with the one or more critical care medical devices. The methods includes generating and transmitting RF energy, wherein at least a portion of said RF energy follows an RF power profile of power versus time having a particular format designed to mitigate interference.

Abstract: Adjustment of a downlink transmit power parameter, such as a ceiling level, is disclosed. Signal-to-noise type information and committed power information can be employed to determine the ceiling level adjustment. A ceiling level can be a predetermined cap on transmission power for downlink channels between a user equipment and a base station. Where there is sufficient headroom in total transmission power and a power level greater than the predetermined ceiling can be effective, the ceiling can be adjusted to greater values than the predetermined value. Where total transmission power is more committed, ceiling adjustment can be prevented. Further, where there is no adequate benefit from increasing the ceiling, the adjustment of the ceiling can be prevented. While some instances can result in optimized transmission levels below the ceiling, instances can also be accommodated where the ceiling is to be increased.

Abstract: An apparatus, system and method for providing interference cancellation and communication resource reservation limits to allocate communication resources in a communication system. In one embodiment, the apparatus includes a processor (1320) and memory (1350) including computer program code. The memory (1350) and the computer program code are configured, with the processor (1320), to cause the apparatus to identify an interval of received signal power levels for interference cancellation of an interfering signal to a primary signal, and generate a message that provides the interval of received signal power levels for the interference cancellation of the interfering signal to the primary signal. In a related embodiment, the memory (1350) and the computer program code are configured, with the processor (1320), to cause the apparatus to determine a communication resource reservation limit, and request an increase in the communication resource reservation limit.

Abstract: Embodiments of the present invention disclose an interference elimination method and apparatus for a multi-antenna system. The method includes: generating an equalization coefficient according to a baseband signal received on a receiving antenna, a channel estimation matrix, and an obtained cross-correlation matrix of transmitted signals of a downlink channel on multiple transmit antennas; and performing interference elimination processing on the baseband signal according to the equalization coefficient.

Abstract: A direct conversion transmitter has a mixer stage to up-convert an input signal to the frequency of a local oscillator (LO). A DC offset circuit is coupled to an input signal port to apply a set of DC offset signal values. A processor determines a set of optimal DC offset signal values by no more than three differential spectral measurements made at the transmitter output port with a test signal applied at the input port. Optimal DC offset signal values are those that, when applied to the input signal at the input port of the transmitter, minimize an LO leakage component of the transmit signal at the output signal port of the transmitter. The optimal DC offset values are stored in memory and retrieved and applied to information bearing signals provided as the input signal once those optimal DC offset values have been determined.

Abstract: 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.

Abstract: The present disclosure relates to amplitude based pre-distortion calibration of an RF communications terminal, such as a cell phone, by transmitting a first standard RF transmit burst from the RF communications terminal to an RF test instrument, which assimilates the first standard RF transmit burst. A calibration control system extracts information regarding the first standard RF transmit burst from the RF test instrument; determines amplitude based distortion of the RF communications terminal using the extracted information; determines amplitude based pre-distortion calibration information using the determined amplitude based distortion; and calibrates the RF communications terminal using the amplitude based pre-distortion calibration information. By using a single-shot transmit burst, calibration times may be minimized.

Abstract: One embodiment of the present invention relates to a method and apparatus are provided herein for reducing the power consumption of a transmission chain while maintaining an acceptable figure of merit (e.g., linearity). In one embodiment, an adaptive biasing element is configured to perform adaptive biasing to reduce current consumption of a transmission chain by adjusting the operating point of one or more transmission chain elements (e.g., power amplifier, mixer, etc.). However, since adaptive biasing may reduce the linearity of a transmitted signal, its use is limited by the degradation of figure of merit caused by the introduced non-linearities. Accordingly, a pre-distortion element may be configured to perform adaptive digital pre-distortion (DPD) on a transmission chain input signal to account for non-linearities generated through the adaptive biasing, therefore allowing the adaptive biasing to further reduce the current consumption while maintaining an acceptable figure of merit.

Abstract: A method and a serving NodeB for adjusting transmit power of a User Equipment (UE) having multiple transmitter chains to reduce relative phase discontinuity (RPD) between a Sounding Reference Signal (SRS) and a Physical Uplink Shared Channel (PUSCH). The NodeB receives from the UE, an RP characteristic of the UE and, based on the RP characteristic, selects an SRS or PUSCH transmit power level for the UE so as to reduce the RPD. The NodeB instructs the UE to set the SRS or PUSCH transmit power level to the level selected by the NodeB.

Abstract: The present invention provides a transmission system, including: a transmitter including a transmitter filter; a receiver including a receiver filter; and a communicative coupling between the transmitter and the receiver; wherein the transmitter filter and the receiver filter are matched for noise reduction, and wherein the combined responses of the transmitter filter and the receiver filter satisfy the Nyquist criteria. Optionally, the transmitter filter includes a pulse shaping quasi digital finite impulse response filter. Optionally, the receiver filter includes an inductor-capacitor ladder based filter.

Abstract: A computational processor uses a binary signal, being a set of 1- or 0-valued elements of a same number as a number of elements in an input signal, to generate computational data whose elements are exclusive OR values between each element of the input signal and a corresponding element in the binary signal at a same position. The modulator 13 modulates the input signal and the computational data according to a primary modulation scheme, and generates primary-modulated signals. An IFFT calculator applies an inverse fast Fourier transformation to the primary-modulated signals to generate inverse transformation data. A transmitter generates a baseband signal based on generated inverse transformation data whose peak-to-average power ratio matches a standard, and generates and transmits a transmission signal from the baseband signal and data specifying computations conducted to generate the inverse transformation data that matches the standard.

Abstract: Disclosed are circuits, techniques and methods for implementing an attenuator in a signal transmission path. In one particular implementation, an attenuation may be adjusted based, at least in part, on a control signal. In another implementation, such an attenuation may be adjusted in coarse increments by varying one or more gate voltages applied one or more transistors. In yet another implementation, adjusting said attenuation in fine increments by varying a bias voltage applied to at least one level shifter.

Abstract: A method for compensating signal distortions in multiple transmitting branches entering a composite amplifier.

Abstract: A data transmission method includes transmitting an encoded data signal in form of a data stream of data bursts between a transmitter and a receiver, making a decision as a function of at least one data transmission parameter as to whether an interference treatment o the data signal to be transmitted will be performed in the transmitter or in the reciver, performing the interference treatment in terms of at least on code in the transmitter, and performing ther interference treatment of the data to be transmitted in terms of at least one further code in the reciver.

Abstract: Systems and methods for wireless communication in a system including a transmitter, a receiver, and a plurality of propagation paths formed between the transmitter and the receiver which are capable of carrying a signal transmitted by the transmitter to the receiver. The method includes transmitting a first signal from the transmitter to the receiver via a propagation path of the plurality of propagation paths, receiving the first signal at the receiver, performing a channel estimation of the first signal to obtain path parameter information of the propagation path, sending the channel estimation from the receiver to the transmitter via the propagation path, predistorting a second signal at the transmitter according to the channel estimation, transmitting the predistorted signal from the transmitter to the receiver via the propagation path, and receiving the predistorted signal at the receiver.

Abstract: An electronic receiver may comprise nonlinear distortion modeling circuitry, interference estimation circuitry, and sequence estimation circuitry. The receiver may receive an orthogonal frequency division multiplexing (OFDM) symbol in the form of an electromagnetic signal. The nonlinear distortion modeling circuitry may generate a nonlinear distortion model that models nonlinear distortion introduced to the received electromagnetic signal en route to the sequence estimation circuitry. The interference estimation circuitry may estimate inter-subcarrier interference present in the received OFDM symbol based on the generated nonlinear distortion model. The estimating of the inter-subcarrier interference may comprise applying the nonlinear distortion model to one or more candidate vectors generated by the sequence estimation circuitry. The sequence estimation circuitry may sequentially process a plurality of received virtual subcarrier values of the OFDM symbol using the estimated inter-subcarrier interference.

Abstract: A method and apparatus for bi-direction training in D2D/cellular networks. An embodiment method includes sending training symbols to sense interference from the cellular UEs, calculating an interference subspace from the cellular UE to each of the D2D UEs, calculating an orthogonal projection matrix based on the interference subspace calculated, and iteratively updating receive filters through forward training and transmit beamformers through backward training after the orthogonal projection matrix is calculated to align the D2D UEs. In an embodiment, training symbols are sent to sense interference from the cellular UE.

Abstract: A transceiver including a filter, a transmitter, a receiver, a measurement module and a gain module. The filter is configured to (i) receive an input signal, and (ii) filter the input signal to generate an output signal. The transmitter is configured to transmit the output signal based on (i) a gain of the transmitter, and (ii) a power output of the transmitter. The receiver is configured to receive the output signal, where the output signal is fed back from the transmitter to the receiver. The measurement module is configured to, based on the output signal, generate a linearity signal, where the linearity signal is indicative of the linearity of the transmitter. The gain module is configured to, based on the linearity signal, adjust the gain of the transmitter to maximize the power output of the transmitter. The filter is configured to filter the input signal based on the linearity signal.

Abstract: Interference in a wireless network is detected by first applying during a detection stage a two-sample Kolmogorov-Smirnov (KS) test to samples obtained from a channel in the wireless network to obtain a KS statistic. When the KS statistic is larger than a predetermine threshold, it is determined that the samples include narrowband interference, and wideband otherwise.

Abstract: Technologies are generally described for a system for controlling an audio signal based on a proximity of, e.g., a user's hand to at least one component of an audio control system. In some examples, an audio control system may include a filter configured to provide an echo signal and a control decision unit configured to provide a control signal based on the echo signal.

Abstract: A transmitter circuit is described. The transmitter circuit includes a first local oscillator that generates a first frequency equal to a duplex frequency. The transmitter circuit also includes a second local oscillator that generates a second frequency equal to a receive frequency. The transmitter circuit further includes a first mixer that combines the first frequency with a first input signal. The transmitter circuit also includes a first feedback loop. The first feedback loop includes a second mixer that combines the second frequency with a transmit signal and a first filter and a first adder that combines an output of the first mixer with an output of the first filter. The transmitter circuit also includes a third local oscillator that generates a third frequency equal to the receive frequency. The transmitter circuit further includes a third mixer that combines the third frequency with an output of the first adder.

Abstract: Adaptive filtering is used to substantially cancel distortion in radio frequency (RF) signals. Such adaptive filtering can be used in an RF transmitting module to pre-compensate an RF signal with compensation (inverse) distortion to cancel inherent transmission path distortion from the RF signal. Adaptive filtering can also be used in a multi-carrier RF receiving module to cancel from a given carrier signal distortion due to cross talk from adjacent carrier signals. Adaptive filtering in an RF transceiver can be used to cancel from a received RF signal distortion arising from leakage of a transmit signal into the receive path.

Abstract: Cross-polar discrimination (XPD) of a dual orthogonal cross-polarized antenna is maximized via a cross-coupling network between base station MIMO branches prior to connection to the base station antenna. In one embodiment, a cross coupling network combines each MIMO branch signal with an attenuated phase reversed (phase shifted) copy of the other MIMO branch signal. The amount of attenuation for each branch is equivalent to the cross polar suppression required for each antenna array. The cross-coupling can be applied at different stages of signal processing within a base station.

Abstract: A receiver circuit receives a signal including a first reference signal from a first antenna port that is allocated to the UE. The receiver circuit includes a descrambling and despreading unit that despreads and descrambles the signal using a spreading code of the first antenna port and a scrambling sequence assigned to the UE to generate a first antenna port signal. The descrambling and despreading unit despreads and descrambles the signal using a spreading code of a second antenna port and the scrambling sequence assigned to the UE, wherein the second antenna port is unallocated to the UE to generate a second antenna port signal. A channel estimator generates a channel estimate of the first antenna port based on the first antenna port signal. An estimation unit estimates an interference and noise covariance measure based on the first antenna port signal, the channel estimate and the second antenna port signal.

Abstract: An OFDM generation apparatus and methods for generating OFDM transmission signals from OFDM symbols, each including a plurality of OFDM subcarriers, for transmission in a multi-carrier data transmission system, is provided. The provided apparatus and method may use a selected mixing frequency for mixing complex time-domain samples of OFDM symbols from a baseband frequency up to a passband frequency to obtain OFDM transmission signals, wherein the mixing frequency is selected such that common phase rotations of the OFDM subcarriers of OFDM symbols with respect to adjacent OFDM symbols of the OFDM transmission signals are avoided or compensated after the mixing. Additional apparatuses and methods for avoidance or compensation of such common phase rotations are also provided.

Abstract: Interference to a received signal is reduced in a wireless network, the interference comprising intermodulation products of at least a first signal and a second signal. Delayed interference signals comprising simulated intermodulation products are generated on the basis of the first signal and the second signal using a range of differing delay values and each of the delayed interference signals is correlated with the received signal to produce data representing a correlation for each delayed interference signal. At least one delay value is selected in dependence on a the data representative of the correlations and an interference signal comprising simulated intermodulation products generated from the first signal and the second signal using the at least one delay value is combined with the received signal.

Abstract: Systems, methods, and devices to enable monitoring of wireless networks are described herein. In some aspects, a low power receiver or a receiver operating in a low power mode scans for signals with a moderate or low duty cycle. If a signal identifying a device or user of the receiver, or a signal indicating that there will be a subsequent data communication, is received, a high power receiver or a receiver operating in a high power mode is activated to receive data communications.

Abstract: A communications device includes a transmitter, a transmission processing device, a receiver, and a reception processing device. The transmission processing device assigns signal-space points within an I/Q signal space to digital signals, which include data values. The reception processing device assigns data values to signal-space points. The transmitter generates a transmission signal from signal-space points to be transmitted. The receiver determines received signal-space points from a received signal. The individual transmitted and received signal-space points provide in each case a smaller spacing distance from adjacent signal-space points than from the origin of the signal space.

Abstract: The present application discloses a method for reporting channel status information in a multi antenna wireless communication system. In more detail, the method includes: receiving a reference signal from a base station; calculating the optimum precoding matrix index (PMI), at which the intensity of a signal from the base station is maximized, on the basis of the reference signal: determining at least one interference PMI from the base station on the assumption that a plurality of interference PMIs corresponding to the optimum PIM are applied; and transmitting information on at least one determined interference PMI to the base station. Beams corresponding to the plurality of interference PMIs are orthogonal to the beams corresponding to the optimum PMI.

Abstract: A system and process that incorporates teachings of the subject disclosure may include, for example, an interference monitor configured to detect occurrences of unintended signals within a communications link. A communications link may carry a down-converted format of a satellite signal from an earth terminal to an integrated receiver and decoder for further network distribution. Depending upon the nature of any such detected unintended signals, the communications link can be “swapped out” for a redundant communications link carrying a down-converted format of the same satellite signal obtained by way of a redundant earth terminal. Other embodiments are disclosed.