Class / Patent application number | Description | Number of patent applications / Date published |
375349000 | Plural signal paths in receiver | 73 |
20080260081 | Real-time channel estimation system - A real-time channel estimation system, which receives a wireless transmission signal through a wireless channel and estimates channel parameters of the wireless channel in real-time. The system includes a channel estimator to receive the wireless transmission signal and output the channel parameters; first and second filters to filter the channel parameters for producing a first and a second sets of filtered channel parameters; first and second calculators to compute according to the first and the second sets of filtered channel parameters and the wireless transmission signal for producing a first and a second probabilities; a comparator to compare the first and the second probabilities for producing an indicative signal; and a multiplexer to receive the indicative signal for accordingly selecting the first or second set of filtered channel parameters as an output. | 10-23-2008 |
20090010369 | USER SELECTION METHOD AND USER SELECTION DEVICE FOR MULTIUSER MIMO COMMUNICATION - The present invention aims to provide a user selection method which can provide a large, multiuser diversity effect with a small amount of calculation in multiuser MIMO systems, the method being a user selection method for multiuser MIMO communication, in which an orthogonal coefficient is calculated using a received SINR from a projection channel vector by using GS orthogonalization, and using the orthogonal coefficient, a correction SINR is calculated, and using this correction SINR, user selection is performed, and for a next user selection, the projection channel vector is updated, and the above processes are applied to all users. | 01-08-2009 |
20090034666 | IQ Imbalance Image Suppression - A WCDMA receiver performs baseband suppression of the image signal component caused by IQ imbalance. An IQ imbalance image scaling factor is computed from conventional channel estimates and estimates of the IQ imbalance image channel, the latter computed using a conjugated scrambling sequence as the reference sequence for despreading. An IQ imbalance image estimate is obtained by scaling the complex conjugate of the received signal by the IQ imbalance image scaling factor, and is subtracted from the input signal prior to applying traditional baseband demodulation algorithms. | 02-05-2009 |
20100002814 | RECEIVER - A receiver for a telecommunications system, wherein the receiver is capable of using a plurality of available alternative receiver sub-systems and the receiver comprises selection means for selecting one of the plurality of receiver sub-systems for use in processing a received signal according to conditions of the propagation channel through which the received signal was received. | 01-07-2010 |
20100014619 | SPACE TIME BLOCK CODED TRANSMIT ANTENNA DIVERSITY FOR WCDMA - A mobile communication system is designed with an input circuit coupled to receive a first plurality of signals (r | 01-21-2010 |
20100111239 | SYSTEM AND METHOD FOR PARALLEL INTERFERENCE CANCELLATION WITH COVARIANCE ROOT PROCESSING - A parallel interference cancellation (PIC) receiver incrementally removes interference from signals in parallel modules in successive stages. For each desired signal, as interfering signals are removed, corresponding updates to a data covariance matrix are modeled as computationally tractable rank-one updates to a root matrix of the covariance matrix. Processing of signals and/or covariance information may be initiated, continued, and/or halted at various stages, e.g., in response to signal or data quality. The PIC receiver using root matrix updates is applicable to a variety of demodulation techniques. | 05-06-2010 |
20100158174 | APPARATUS AND METHOD FOR INTERFERENCE MITIGATION - An apparatus in a wideband radio transceiver for mitigating interference between a wideband radio operating in a wide frequency band and a narrowband radio operating in a narrow frequency band within the wide frequency band. The effects of transmissions by the wideband radio on the narrowband radio are reduced by creating by the wideband radio, a transmitter notch of decreased transmit power centered at a frequency in the wide frequency band that is fixed in relation to the wideband carrier frequency. The wideband carrier frequency is then adjusted so that the transmitter notch is aligned with the second radio's narrow frequency band. The effects of transmissions by the narrowband radio on the wideband radio are reduced by creating by the wideband radio, a fixed receiver notch of decreased receiver gain in the wideband receiver, and aligning the narrowband signal with the fixed receiver notch. | 06-24-2010 |
20100239057 | DRIFT CANCELLATION TECHNIQUE FOR USE IN CLOCK-FORWARDING ARCHITECTURES - A circuit includes a frequency synthesizer, N phase mixers coupled to the frequency synthesizer, a plurality of receivers, and a calibration circuit. The frequency synthesizer is to receive a reference clock signal and is to output a primary clock signal. A respective phase mixer in the N phase mixers is to output a respective secondary clock signal having a corresponding phase. A respective receiver in the plurality of receivers is coupled to two of the N phase mixers, and at a respective time is to receive data in accordance with the respective secondary clock signal from one of the two phase mixers coupled to the respective receiver. The calibration circuit is to calibrate a secondary clock signal output by a respective phase mixer in the N phase mixers by adjusting the phase of the secondary clock signal of the respective phase mixer. | 09-23-2010 |
20100254498 | APPARATUS AND METHOD FOR IDENTIFYING TRANSMITTER IN DIGITAL BROADCASTING SYSTEM - A method for identifying a transmitter in a digital broadcasting system includes: receiving a broadcast signal in which a TxID sequence for identification of a transmitter is embedded; correlating the received broadcast signal with a plurality of elementary code sequences of a pseudo-random sequence sequentially; and identifying the transmitter by using the correlation results. | 10-07-2010 |
20110013735 | PROGRESSIVE PARALLEL INTERFERENCE CANCELLER AND METHOD AND RECEIVER THEREOF - A progressive parallel interference canceller (PPIC) and a method and a receiver thereof are illustrated. The PPIC reconstructs each subchannel interference reconstruction signal through several iterations and subtracts the corresponding subchannel interference reconstruction signal from each subchannel frequency-domain reception signal to obtain a subchannel frequency-domain signal. Thereby, according to the present disclosure, inter-channel interference can be cancelled without re-performing channel coding or estimating the signal to noise ratio (SNR) or frequency offset. | 01-20-2011 |
20110038448 | MULTI-MODE RECEIVER WITH ADAPTIVE MODE SELECTION - Receivers and methods are provided that include multiple modes of processing signals from multiple antennas. These include legacy, SAIC (single antenna interference cancellation) and MSRD. Various methods are provided for selecting an appropriate receiver processing function. These include looking at correlation and gain imbalance between antennas, looking at the processing gain resulting from one or more of the receiver processing functions, and looking at the equalization quality of at least two receiver processing functions. | 02-17-2011 |
20110216859 | High-Frequency Signal Receiver Simultaneously Receiving Several Such Signals - The present invention relates to a high-frequency signal receiver simultaneously receiving several such signals received by at least one antenna and comprising analog/digital conversion circuits converting these signals into digital form, and this receiver is characterized in that it comprises individual filtering digital circuits respectively filtering each of the carrier frequencies of these signals and digital processing circuits. | 09-08-2011 |
20110243285 | ACTIVE ANTENNA ARRAY AND METHOD FOR CALIBRATION OF THE ACTIVE ANTENNA ARRAY - The disclosure relates to an active antenna array for a mobile communication system which comprises a plurality of receive paths, a sounding signal generator generating a sounding signal, and a coupler for coupling the sounding signal into at least one of a plurality of receive paths. A sounding signal extractor substantially removes the sounding signal from digitised ones of the receive signals to form a wanted signal. The disclosure also provides a method for the calibration of the receive path of the active antenna array. | 10-06-2011 |
20110261911 | RECEIVER CAPABLE OF REDUCING LOCAL OSCILLATION LEAKAGE AND IN-PHASE/QUADRATURE-PHASE (I/Q) MISMATCH AND AN ADJUSTING METHOD THEREOF - An adjusting method for reducing local oscillation leakage or I/Q mismatch in a receiver includes the steps of: (a) detecting a current extent of local oscillation leakage or I/Q mismatch; (b) determining if an adjusting direction is correct with reference to the current extent of local oscillation leakage or I/Q mismatch thus detected, maintaining the adjusting direction if correct, and reversing the adjusting direction upon determining that the adjusting direction is incorrect; and (c) adjusting a control signal according to the adjusting direction. | 10-27-2011 |
20120076249 | APPARATUS AND METHOD FOR RECEIVING DUAL BAND RF SIGNALS SIMULTANEOUSLY - Disclosed is a dual band receiver which includes an analog-to-digital converter configured to convert a dual band analog RF signal into a dual baseband digital signal; and a first signal extractor configured to generate a first path signal and a second path signal from the dual baseband signal and to extract a first baseband signal using a relative sample delay difference between the first and second path signals, wherein the dual baseband signal includes the first baseband signal and a second baseband signal, the first path signal is a signal obtained by sample delay of the dual baseband signal and then down sampling of a resultant signal, and the second path signal is a signal obtained by down sampling of the dual baseband signal without sample delay. | 03-29-2012 |
20120082276 | COMPENSATING FOR UNWANTED INTERFERENCE IN A COMMUNICATIONS RECEIVER - Method and apparatuses are disclosed to substantially compensate for various unwanted interferences and/or distortions within a communications receiver. Each of these apparatuses and methods estimate the various unwanted interferences and/or distortions within the communications receiver. Each of these apparatuses and methods remove the estimates of the various unwanted interferences and/or distortions within the communications receiver from one or more communications signals within the communications receiver to substantially compensate for the various unwanted interferences and/or distortions. | 04-05-2012 |
20120106686 | DIGITAL I/Q IMBALANCE COMPENSATION IN A QUADRATURE RECEIVER - An apparatus and method reduce distortion in a processed signal. The apparatus includes a first receive path, a second receive path, a summation unit, and a compensation unit. The first receive path is configured to process a received analog signal into a first digital signal. The second receive path is configured to process the received analog signal with a phase shift into a second digital signal. The summation unit is configured to sum the first and second digital signals to form a processed digital signal. The compensation unit is configured to identify a conjugate of the processed digital signal, apply a weighting factor to the conjugate of the processed digital signal to form a weighted signal, and subtract the weighted signal from the processed digital signal to reduce the distortion. | 05-03-2012 |
20120183108 | SYSTEMS AND METHODS FOR MULTICHANNEL NOISE REDUCTION - Systems and methods for multichannel noise reduce are provided. One method includes acquiring a multichannel signal, obtaining a noise correlation between a plurality of channels of the multichannel signal, and obtaining a signal characteristic in each of the plurality of channels. The method also includes removing signal noise based on (i) the correlated noise and (ii) at least one of an uncorrelated noise in each channel or the obtained signal characteristic in each channel. | 07-19-2012 |
20120201336 | Wireless Communication Unit and Method for Channel Estimation - A method is provided for estimating at least one offset of a communication in a multicarrier communication system. The method comprises receiving a plurality of subcarriers wherein the plurality of subcarriers contain the subcarrier that is subject to the distortion; and generating a plurality of first channel estimates for a respective plurality of received subcarriers that are not subject to the distortion. The method further comprises processing a number of the plurality of first channel estimates for the respective plurality of received subcarriers that are not subject to the distortion to generate a second channel estimate for the subcarrier that is subject to the distortion; and estimating an offset associated with the subcarrier that is subject to the distortion. | 08-09-2012 |
20120269306 | METHOD AND APPARATUS FOR CROSS-POLARIZATION COMPENSATION - Methods and apparatus for compensating for polarization loss in communications systems that use orthogonally spaced polarization. In one example, a signal processing method uses a statistical decorrelation process to separate out two orthogonally polarized desired signals from noisy received signals that include these orthogonally polarized desired signals along with their cross-polarized components, thereby compensating for the polarization contamination. | 10-25-2012 |
20120294399 | Low-Complexity Diversity Reception - A system may comprise a plurality of signal processing paths, a bin-wise combiner, an inverse transformation block, and a DAC. Each signal processing path may comprise a transformation block that is operable to transform a first time-domain digital signal to an associated frequency-domain signal having a plurality of subband signals. The bin-wise combiner may be operable to combine corresponding subband signals of the plurality of signal processing paths. The inverse transformation block may be operable to transform output of the bin-wise combiner to an second time-domain signal. The DAC may be operable to converts the second time-domain signal to a corresponding analog signal. | 11-22-2012 |
20120300888 | VIRTUAL WEAVER ARCHITECTURE FILTER - A virtual Weaver architecture filter is implemented using a sampling mixer that successively processes samples of the input signal in round-robin fashion and provides a sum of the samples as multiplied by coefficients emulating quadrature sinusoidal waveforms. A virtual rather than actual local oscillator is reliably implemented without mismatch. Filtering between the Weaver mixers is eliminated in favour of filtering at the sampling input and effective time division multiplexing is achieved by selecting between resistor combinations that implement different scaling coefficients, resulting in an efficient analog implementation of a virtual Weaver architecture. | 11-29-2012 |
20120328060 | METHOD AND APPARATUS FOR CHANNEL ESTIMATION IN MULTI-PATH CHANNEL - A channel estimation method in a multipath channel includes receiving a signal from a channel having multipath, obtaining information related to the number of paths and synchronization information related to each path from the received signal, estimating a channel value using the obtained information related to number of paths and synchronization information related to each path, calculating a metric using those obtained information and an impulse response value of Square Raised Cosine (SRRC) filter, and correcting the estimated channel value using the calculated metric. | 12-27-2012 |
20130022161 | TURBO CHANNEL ESTIMATION FOR OFDM SYSTEMS - A system and method for estimating a channel in a wireless receiver is disclosed. The method comprises receiving a block of “n” transmitted symbols, the symbols including pilot symbols and “d” data symbols, estimating a channel using the pilot symbols to create a channel estimate, choosing a group of “m” strongest symbols from the “d” received symbols, compensating the “m” strongest symbols using the channel estimate to create a group of “m” compensated symbols, re-estimating the channel using the group of “m” compensated symbols and pilot symbols; and either ( | 01-24-2013 |
20130101073 | Adaptive Interference Canceller in a Digital Phase Array - A digital phased array may include a plurality of antenna elements forming a main array of the digital phased array, a plurality of mixers configured to down-convert data received at respective ones of the antenna elements, a plurality of analog-to-digital converters configured to digitize data provided by corresponding ones of the mixers, and a digital signal processor. The digital signal processor may be configured to receive digitized data including at least one interference signal and at least one desired signal, determine an angle of arrival of the at least one interference signal, steer a beam of the main array toward the at least one interference signal based on the determined angle of arrival, and perform interference cancelation relative to the at least one interference signal. | 04-25-2013 |
20130114769 | DYNAMIC RECEIVER SWITCHING - Techniques for dynamically selecting a number of downconversion paths used in a variety of receiver, wideband receiver architectures, for example, zero-IF or low-IF. In an exemplary embodiment, a first downconversion path is configured to downconvert a signal derived from an RF signal using a first mixing frequency. A second downconversion path is further configured to downconvert a signal derived from the RF signal using a second mixing frequency distinct from the first mixing frequency. The second downconversion path may be selectively enabled or disabled based on a detected level of an interferer in the frequency spectrum. For example, if the interferer level is less than a predetermined threshold, a fewer number of downconversion paths, for example, one path, may be enabled. If the interferer level is greater than a predetermined threshold, then a greater number of downconversion paths, for example, two or more paths, may be enabled. | 05-09-2013 |
20130177116 | Linearization of Multi-Antenna Receivers with RF Pre-Distortion - A receiver includes a first receiver chain configured to receive a first input signal and a second receiver chain configured to receive a second input signal. A first phase predistorter is provided in the first receiver chain and is configured to shift a phase of the first input signal by a first phase shift φ′ | 07-11-2013 |
20130188761 | Method, Apparatus and Computer Program for Calculating a Noise Covariance Estimate - A final NOCE (noise covariance estimate) for reducing noise in a first channel of a receiver with a plurality of antennas is calculated. A first raw NOCE for the first channel is calculated, wherein a raw NOCE for a channel is an initial estimate of the covariance of noise in that channel between the plurality of antennas. At least a second raw NOCE for a second channel is calculated. A metric using the first and second raw NOCEs is calculated. The metric is used to determine whether the second raw NOCE should be included in the calculation of the final NOCE. | 07-25-2013 |
20130230130 | DISTORTION AND ALIASING REDUCTION FOR DIGITAL TO ANALOG CONVERSION - Distortion and aliasing reduction for digital to analog conversion. Synthesis of one or more distortion terms made based on a digital signal (e.g., one or more digital codewords) is performed in accordance with digital to analog conversion. The one or more distortion terms may correspond to aliased higher-order harmonics, distortion, nonlinearities, clipping, etc. Such distortion terms may be known a priori, such as based upon particular characteristics of a given device, operational history, etc. Alternatively, such distortion terms may be determined based upon operation of a device and/or based upon an analog signal generated from the analog to conversion process. For example, frequency selective measurements made based on an analog signal generated from the digital to analog conversion may be used for determination of and/or adaptation of the one or more distortion terms. One or more DACs may be employed within various architectures operative to perform digital to analog conversion. | 09-05-2013 |
20130235959 | Filter - An apparatus and method suppress unwanted signal components in receiving signals during wireless communication. A first circuitry is arranged to process a first signal, a second circuitry is arranged to apply transferred impedance filtering on a second signal according to a filter clock frequency, a signal branching circuitry is arranged to branch an input signal into the first circuitry and the second circuitry, and a signal combining circuitry is arranged to combine the processed first signal and the filtered second signal such that signal components of the first signal processed in the first circuitry and the filtered second signal are in-phase for signal frequencies equal to the filter clock frequency. | 09-12-2013 |
20130235960 | METHOD AND DEVICE FOR ACQUIRING PRECODING MATRIX - A method and device for acquiring a precoding matrix are provided by the present invention. The method for acquiring a precoding matrix includes: for each receiving end, selecting the interference vectors as the interference space basis vectors from whole interference vectors, representing the remaining interference vectors as the linear combination of the interference space basis vectors, wherein the remaining interference vectors are the interference vectors in the whole interference vectors of the receiving end except the interference vectors which act as the interference space basis vectors ( | 09-12-2013 |
20130251080 | LOW NOISE AMPLIFIER - A low noise amplifier for use in a front end includes a multiple-input interference canceller configured to receive a plurality of input signals, and output a signal from which an interference component is removed. The multiple-input interference canceller includes a plurality of gain control blocks configured to receive each of the input signals, and perform gain control, and a coupling block configured to couple output signals of the gain control blocks. | 09-26-2013 |
20130259176 | Channel Estimation Filter Normalization - Disclosed are various embodiments providing processing circuitry for selecting a channel estimation filter from a plurality of channel estimation filters based on a channel quality metric, the selected channel estimation filter being associated with an intrinsic coefficient. The processing circuitry may then determine a scaled coefficient, the scale coefficient being based on scaling the intrinsic coefficient with respect to a bit size constraint, the bit size constraint being determined by a bit length of a multiplication circuitry operand. Moreover, the processing circuitry may generate an output based on the scaled coefficient and an input signal. | 10-03-2013 |
20130315356 | Techniques for Decoding Transmitted Signals Using Reactive Taboo Searches (RTS) - Techniques for enabling an estimate of a transmittal signal vector, given a received signal vector and a channel matrix to be computed, are provided. An initial solution signal vector for the estimate is calculated, and based on the initial estimate, a pool of possible solutions is generated. Methods described herein may be iterative in nature, and may cycle through possible estimates of the transmitted signal vector so as to continually improve the estimates and the pool of possible estimates. The methods may terminate once stopping criteria are reached. In some example methods, solutions may be marked at taboo and a taboo period can be established that indicates a number of subsequent iterations for which the current solution signal vector cannot be considered. | 11-28-2013 |
20130322584 | SYSTEMS AND METHODS FOR FAST AND PRECISE FREQUENCY ESTIMATION - Systems and methods are provided for fast and precise estimation of frequency with relatively minimal sampling and relatively high tolerance to noise. | 12-05-2013 |
20130322585 | METHOD AND SYSTEM FOR DIVERSITY PROCESSING UTILIZING A PROGRAMMABLE INTERFACE SUPPRESSION MODULE - Aspects of a method and system for diversity processing utilizing a programmable interface suppression module may include one or more circuits that are operable to program an interference suppression module based on one or more interference cancellation parameters. A plurality of weighting factor values may be computed based on the one or more interference suppression parameters and a received plurality of multipath signals. A plurality of estimated signal may be generated based on the plurality of weighting factor values. A plurality of updated estimated signals may be generated based on the plurality of estimated signals. A plurality of interference suppressed signals may be generated based on the plurality of updated estimated signals. | 12-05-2013 |
20130343499 | CHANNEL ESTIMATION METHOD AND APPARATUS - A channel estimation method and apparatus are provided. The channel estimation method includes: extracting pilot data in a received signal; performing pilot channel estimation by using the extracted pilot data to obtain transmission coefficients of multiple groups of pilot channels; and obtaining a transmission coefficient of a data channel through non-linear interpolation processing by using the obtained transmission coefficients of the multiple groups of pilot channels. Solutions provided in the embodiments of the present invention help improve the channel estimation precision in a fast time-changing channel environment, thereby improving the system performance. | 12-26-2013 |
20130343500 | DEVICE, SYSTEM AND METHOD OF COMBINING RECEIVED WIRELESS COMMUNICATION SIGNALS - Some demonstrative embodiments include devices, systems and/or methods of combining received wireless communication signals. For example, a device may include a radio-frequency (RF) combiner to combine first and second wireless communication RF signals of a wireless communication frame received via first and second respective antennas, into a combined signal; and a base-band phase estimator to estimate a phase difference between the first and the second antennas, and to provide to the RF combiner a feedback corresponding to the phase difference, wherein the radio-frequency combiner is to combine the first and the second RF signals according to the feedback. | 12-26-2013 |
20140064419 | APPARATUS AND METHOD FOR IMPROVING OFDM RECEIVER PERFORMANCE IN THE PRESENCE OF NARROWBAND INTERFERERS - In an Orthogonal Frequency Division Multiplex (“OFDM”) system, the problem of an interferer reducing the signal-to-noise ratio of a signal can be mitigated by generating an interferer-correction signal and subtracting it from the signal to be processed. The amplitude, frequency and phase of the interferences are determined first. The frequency is estimated by averaging the squared-magnitude of multiple FFTs of the incoming signal and then locating the spectral peaks. The phase and amplitude may be estimated from this FFT outputs or through a process of correlation in the time domain. The interferer-correction signal is generated from the estimated amplitude, frequency, and phase. The correction to be subtracted from the main signal in order to reduce the effect of the interference may be generated in the time or frequency domain. The subtraction of the correction may also be implemented in the time or frequency domains. | 03-06-2014 |
20140086373 | Method of Channel Estimation and a Channel Estimator - A method includes receiving a signal over a multi-path channel, generating a plurality of observation vectors of the received signal, generating a channel covariance matrix of the plurality of observation vectors, and identifying a first path by projecting a pulse shaping vector on the channel covariance matrix at different time offsets and selecting the maximum thereof as the first path. Thereafter, further paths can be identified. In each case, an n-th path is identified by projecting the pulse shaping vector into a null space of n-1 previously identified paths at different time offsets and the maximum thereof is selected as an n-th path. | 03-27-2014 |
20140112422 | Method and Apparatus for Improving Communication Rate - A method and an apparatus are provided for improving a communication rate, which are used in a terminal working in a multiple-input multiple-output (MIMO) state. The method includes: obtaining strength of a first signal received in a first path connected to a first antenna and strength of a second signal received in a second path connected to a second antenna; and adjusting the first path or/and the second path according to a difference between the strength of the first signal and the strength of the second signal, so as to reduce an unbalance degree between the first path and the second path, thereby improving the communication rate. By adopting the present invention, improvement of a rate of an antenna may be achieved by adjusting a balance between the first and second paths. | 04-24-2014 |
20140119484 | Transmission of Symbols in a MIMO Environment using Alamouti Based Codes - A method for transmitting data in a multiple-input-multiple-output space-time coded communication using a mapping table mapping a plurality of symbols defining the communication to respective antennae from amongst a plurality of transmission antennae and to at least one other transmission resource. The mapping table may comprise Alamouti-coded primary segments and may also comprise secondary segments, comprising primary segments. The primary segments in the secondary segments may be defined in accordance to an to Alamouti based code pattern applied at the segment level to define a segment-level Alamouti based code. | 05-01-2014 |
20140119485 | APPARATUS AND METHOD FOR RECEIVING DUAL BAND RF SIGNALS SIMULTANEOUSLY - Disclosed is a dual band receiver which includes an analog-to-digital converter configured to convert a dual band analog RF signal into a dual baseband digital signal; and a first signal extractor configured to generate a first path signal and a second path signal from the dual baseband signal and to extract a first baseband signal using a relative sample delay difference between the first and second path signals, wherein the dual baseband signal includes the first baseband signal and a second baseband signal, the first path signal is a signal obtained by sample delay of the dual baseband signal and then down sampling of a resultant signal, and the second path signal is a signal obtained by down sampling of the dual baseband signal without sample delay. | 05-01-2014 |
20140146929 | DEVICE FOR ELIMINATING LOCAL PERTURBATIONS FOR REFERENCE RECEIVER OF GNSS GROUND STATIONS - The present invention relates to a device for eliminating the perturbation signals received by a reference GNSS station. | 05-29-2014 |
20140146930 | RECEIVER AND RECEPTION METHOD FOR ESTIMATING CHANNEL IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS SYSTEM - A receiver and reception method for estimating a channel in an Orthogonal Frequency Division Multiple Access (OFDMA) system is provided. The receiver includes a delay estimator for estimating, from a signal received from a transmitter through multipaths, at least one of an average time delay of the multipaths and a time delay of one of the multipaths having a maximum power among the multipaths, a rotator for circular-rotating the received signal using the estimated delay, and a channel estimator for estimating a channel impulse response of the circular-rotated signal. | 05-29-2014 |
20140153677 | ENHANCED RECEPTION OF PRECODING VECTOR SWITCHING (PVS) - A method includes, in a mobile communication terminal, receiving a signal including multiple instances of a synchronization signal transmitted in multiple respective time periods, wherein each instance is precoded with a respective precoding scheme that is selected from a set of precoding schemes in accordance with a precoding alternation pattern. A subset of the instances of the synchronization signal is selected, in accordance with an instance selection pattern that ensures that at least one of the instances of the synchronization signal is received in the terminal with at least a predefined quality. Only the instances belonging to the selected subset are decoded. | 06-05-2014 |
20140177768 | Digital Calibration of Analog Distortion Using Split Analog Front-End - A receiver is disclosed that is capable of correcting for harmonic distortion injected into received analog signals. The receiver splits the analog signal in the analog front-end and modifies the split analog signals with a difference signal. After amplification and/or sampling, the modified analog signals are recombined in a main data pathway and are kept separate in a secondary pathway. Utilizing the difference signal, a feedback loop that includes distorters and an LMS filter detects the distortion coefficient of the harmonic distortion. A distorter in the main data pathway utilizes the detected distortion coefficient to correct the harmonic distortion in the analog signal. | 06-26-2014 |
20140219404 | IMPLEMENTING BLIND TUNING IN HYBRID MIMO RF BEAMFORMING SYSTEMS - A system and a method for applying a blind tuning process to M antennas coupled via N beamformers to a multiple input multiple output (MIMO) receiving system having N channels, wherein M>N, are provided herein. The method includes the following steps: Periodically measuring channel fading rate at a baseband level to determine the number of antennas L out of K antennas connected to each one of the beamformers, to be combined at each one of the N beamformers; assigning the antennas to the subset L according to some criteria such as best quality indicator; repeatedly applying a tuning process to L antennas in each one of the N beamformers. | 08-07-2014 |
20140233686 | DEVICE FOR REMOVING PARTIAL DISCHARGE NOISE AND METHOD OF DIAGNOSING THE SAME - There are provided a device for removing partial discharge noise and a method of diagnosing the same. The device includes a noise removing device configured to remove noise of a partial discharge signal using a reaction rate difference of signals when the partial discharge signal is generated, and output a signal in which noise is removed, a laser module configured to output a laser beam to a surface of a power device when the partial discharge signal is generated and extract sound wave and vibration data from a reflection signal of the laser beam, a correlation analyzing unit configured to compare the partial discharge signal in which noise is removed input through a sensor connecting unit and the sound wave and vibration data extracted through the laser module, and analyze a correlation, and a partial discharge diagnostic unit configured to perform partial discharge diagnosis on a signal that matches the partial discharge signal in which noise is removed with at least one of a generation cycle, a time, and a phase of the sound wave and vibration data based on a result of correlation analysis of the correlation analyzing unit. | 08-21-2014 |
20140294130 | RECEIVER AND SIGNAL PROCESSING METHOD - A receiver includes a detector to detect an interfered-with carrier from a received and demodulated signal, a fast Fourier transform computation part to perform fast Fourier transform to convert a time domain signal to a frequency domain signal and adjust an output power level of a desired carrier wave contained in the frequency domain signal based upon the detected interfered-with carrier, and a channel estimation part to estimate a channel characteristic based upon a non-interfered-with pilot signal that is not subject to influence of the interfered-with carrier and an interpolation value interpolated based upon the non-interfered-with pilot signal, the non-interfered-with pilot signal being obtained by removing, based upon the interfered-with carrier, an interfered-with pilot signal that is subject to the influence of the interfered-with carrier and an interpolation value interpolated based upon the interfered-with pilot signal. | 10-02-2014 |
20140301512 | METHODS AND APPARATUS FOR JOINT DEMODULATION WITH MAX-LOG MAP (MLM) - Certain aspects of the present disclosure relate to techniques and apparatus for performing joint demodulation using a Max-Log MAP algorithm in wireless communications systems. An exemplary method generally comprises receiving a signal comprising one or more serving streams and one or more interfering streams; and processing the signal by performing joint demodulation using a max log map (MLM) algorithm for at least one of the one or more serving streams or at least one of the one or more interfering streams. | 10-09-2014 |
20140307839 | RECEIVER WITH INPHASE-QUADRATURE IMBALANCE COMPENSATION AND INPHASE-QUADRATURE IMBALANCE COMPENSATION METHOD THEREOF - A receiver with Inphase-Quadrature (I-Q) imbalance compensation and an I-Q imbalance compensation method thereof are provided. The receiver chooses a first receiving signal which includes a first data and a first noise, as well as a second receiving signal which includes a second data and a second noise from a plurality of receiving signals. The first data have a first positive frequency data and a first negative frequency data, while the second data have a second positive frequency data and a second negative frequency data. The receiver calculates an I-Q imbalance compensation parameter according to the first receiving signal and the second receiving signal, and compensates for a third receiving signal according to the I-Q imbalance compensation parameter. The I-Q imbalance compensation method is applied to the receiver to implement the aforesaid operations. | 10-16-2014 |
20140334580 | RECEIVE ONLY SMART GROUND-TERMINAL ANTENNA FOR GEOSTATIONARY SATELLITES IN SLIGHTLY INCLINED ORBITS - A receive only smart antenna with a command pointing option for communicating with geostationary satellites that autonomously detects the directions from which desired signal are received, and steer the multiple beams accordingly. An array feed is used to illuminate a parabolic reflector. Each feed element of the receive only smart antenna is associated with a unique beam pointing direction. As a receiver is switched to different feed elements, the far-field beam is scanned, making it possible to track a geostationary satellite in a slightly inclined orbit. This eliminates the need for mechanical tracking and maintains high antenna gain in the direction of the geostationary satellite. The receive only smart antenna also features capabilities to form multiple simultaneous beams supporting operations of multiple geo-satellites in closely spaced slightly inclined orbits. The designs can support orthogonal beams for enhanced bandwidth capacity via multiple beams with excellent spatial isolation. | 11-13-2014 |
20140362959 | SINGLE CABLE INCLUDING MULTIPLE INTERCONNECTIONS BETWEEN TWO RADIO UNITS FOR CROSS POLARIZATION INTERFERENCE CANCELLATION - An outdoor radio communication system comprises a first radio unit, a second radio unit, and a single cable coupling the first radio unit to the second radio unit. Each radio unit includes a downconverter, a radio processor that is communicatively coupled to the downconverter, and a XPIC module. The cable further includes a first twisted-pair of wires for communicatively coupling the first downconverter to the second XPIC module and a second twisted-pair of wires for communicatively coupling the second downconverter to the first XPIC module. The first XPIC module generates a first reference signal using a signal from the second downconverter to cancel cross-polarization interference in an output signal of the first radio processor. Similarly, the second XPIC module generates a second reference signal using a signal from the first downconverter to cancel cross-polarization interference in an output signal of the second radio processor. | 12-11-2014 |
20140369451 | DIRECT SAMPLING RECEIVER WITH CONTINUOUS-TIME MDAC - Methods and apparatuses are described for a direct sampling receiver having high dynamic range and low noise figure with a continuous-time (CT) multiplying digital-to-analog converter (MDAC) architecture. In a multipath architecture, the input signal is sampled in the quantizer path, but not the CT signal path. In the CT signal path, only a filtered residue signal is sampled. Coarse bits generated in the quantizer path and fine bits generated in the input signal path are digitally combined to reconstruct the analog input signal in the digital domain. Filtering, aperture error control and digital equalization remove sources of errors, resulting in high performance. Advantages include toleration of multiple blocker signals, simultaneous reception of multiple weak channels and/or strong and weak channels, operation with simplified gain control and reduced pre-amplification as well as operation without excessive power consumption, external filters and tunable local oscillator (LO). | 12-18-2014 |
20150036772 | Observation Of The True Channel From Band-Limited Frequency Domain Observations - A radio device receives a band-limited signal and estimates signal components beyond the band edges to extend the signal and eliminate the band-limited effects. The extended signal is transformed to the time domain to produce an estimate of the true time domain channel. | 02-05-2015 |
20150043687 | INTRA-FREQUENCY AND INTER-RAT RECEIVER - Techniques are described for wireless communications. In one example, multiple signals including at least a wireless local area network (WLAN) signal and a cellular signal may be received over a bandwidth of an unlicensed radio frequency spectrum band. Digital samples of the signals may be stored in a buffer. At least a portion of the WLAN signal may be reconstructed from the stored digital samples and removed from the stored digital samples before the contents of the buffer are converted to the frequency domain for demodulation and decoding of the cellular signal by a cellular receiver. In another example, multiple signals may be received over a bandwidth of an unlicensed radio frequency spectrum band, and it may be determined whether to apply codeword-level interference cancelation (CWIC) or symbol-level interference cancelation (SLIC) to remove an interference signal in the multiple signals. | 02-12-2015 |
20150063508 | HIGH DYNAMIC RANGE RADIO ARCHITECTURE WITH ENHANCED IMAGE REJECTION - A circuit for down-converting an RF signal to a baseband signal includes a trans-admittance amplifier adapted to receive the RF signal and generate in response a pair of differential current signals. The circuit further includes a trans-impedance amplifier having at least four mixers and at least four linear amplifiers. The four mixers frequency down-convert the pair of differential current signals to generate four pairs of differential baseband current signals, wherein each pair of the differential baseband current signals has a different phase and is associated with each of the linear amplifiers. Additionally, the circuit includes a summing block that generates an in-phase signal using a first weighted sum of the four different baseband current signals and a quadrature signal using a second weighted sum of the four different baseband current signals. The circuit further includes an analog-to-digital converter for converting the in-phase and quadrature signals to respective digital representations. | 03-05-2015 |
20150085961 | Pilot Design for Wireless System - The description herein relates to pilot designs for an Orthogonal Frequency Division Multiplexing (OFDM) based communication system. In at least one embodiment, the communication system is one operating according to the IEEE 802.16m, or WiMax, standard. In general, an OFDM transmitter operates to insert pilot symbols into a resource of a transmit frame according to a predetermined staggered pilot symbol pattern defining pilot symbol locations within the resource of the transmit frame. The predetermined pilot symbol pattern is defined such that pilot symbols are located at or near time boundaries of the resource, at or near frequency boundaries of the resource, or both. By doing so, when generating a channel estimate for the communication channel between the OFDM transmitter and an OFDM receiver based on the pilot symbols, extrapolations needed to estimate the channel near the boundaries of the resource are optimized, thereby improving overall channel estimation accuracy. | 03-26-2015 |
20150085962 | CANCELING NARROWBAND INTERFERING SIGNALS IN A DISTRIBUTED ANTENNA SYSTEM - Canceling narrowband interfering signals in a distributed antenna system is provided. In one aspect, a cancellation sub-system includes a decimator module, a filter, an interpolator module, and a combiner module coupled to the uplink path and a reference path in parallel with the uplink path. The reference path includes the decimator module, the filter, and the interpolator module. The decimator module decimates a reference signal sampled from an uplink signal traversing an uplink path of the remote antenna unit. Each of the uplink signal and the reference signal includes a narrowband interfering signal component. The filter generates a cancellation signal from the reference signal by attenuating the reference signal outside a frequency band that includes the interfering signal component. The interpolator module interpolates the cancellation signal to a sampling rate of the uplink signal. The combiner module can subtract the cancellation signal from the uplink signal. | 03-26-2015 |
20150103960 | IQ IMBALANCE ESTIMATION USING BROADCAST SIGNALS - The present disclosure is described in the exemplary context of a Long Term Evolution (LTE) cellular network and is directed to a method and apparatus for estimating a gain and phase imbalance between an in-phase path and a quadrature path of a receiver operating in such a network. The method and apparatus specifically exploit channel coherence in time and frequency, and the properties of the Primary Synchronization Signal (PSS), and/or the Secondary Synchronization Signal (SSS), and/or information in the Physical Broadcast Channel (PBCH), all of which are defined by the LTE standard, to estimate the gain and phase imbalance of the receiver while it remains connected to a base station to receive data. | 04-16-2015 |
20150124915 | METHOD AND SYSTEM FOR TIME INTERLEAVED ANALOG-TO-DIGITAL CONVERTER TIMING MISMATCH ESTIMATION AND COMPENSATION - Methods and systems for time interleaved analog-to-digital converter timing mismatch calibration and compensation may comprise receiving an analog signal on a chip, converting the analog signal to a digital signal utilizing a time interleaved analog-to-digital-converter (ADC), and reducing a blocker signal that is generated by timing offsets in the time interleaved ADC by estimating complex coupling coefficients between a desired digital output signal and the blocker signal. A decorrelation algorithm may comprise a symmetric adaptive decorrelation algorithm. The received analog signal may be generated by a calibration tone generator on the chip. An aliased signal may be summed with an output signal from a multiplier. The complex coupling coefficients may be determined utilizing the decorrelation algorithm on the summed signals. A multiplier may be configured to cancel the blocker signal utilizing the determined complex coupling coefficients. | 05-07-2015 |
20150139371 | MULTI-BAND RECEIVER - A multi-band receiver according to an embodiment of the present invention includes an analog-to-digital converter configured to convert multi-band analog radio signals into a digital baseband signal, and a first signal extracting unit configured to generate a first path signal by changing a sampling rate of the digital baseband signal and sample-delaying the digital baseband signal, and generate a second path signal by bypassing the digital baseband signal, wherein the first signal extracting unit extracts a first baseband signal using a group delay difference between the first and second path signals caused by a sample delay difference between the first and second path signals. | 05-21-2015 |
20150139372 | SUB-SAMPLING RECEIVER - Provided is a wireless signal receiver including: an analog-digital converter (ADC) converting an analog RF signal into a digital baseband signal; and a sub-sampling block dividing and processing the digital baseband signal into a first path signal and a second path signal, and extracting a complex baseband signal by using a relative sample delay difference between the first and second path signals, wherein the first path signal is a signal obtained by adjusting a sample delay and sampling rate of the digital baseband signal, and the second path signal is a signal obtained by filtering without adjusting the sampling rate of the digital baseband signal. | 05-21-2015 |
20150333950 | METHODS AND DEVICES FOR HANDLING CHANNEL MISMATCHES OF AN I/Q DOWN-CONVERTED SIGNAL AND A TWO-CHANNEL TI-ADC - A method and device for handling an in-phase and quadrature (“I/Q”) channel mismatch of an I/Q down-converted signal, and a use of the device. A discrete-time complex valued signal r(n) based on an analog-to-digital conversion of the I/Q down-converted signal is obtained. The obtained discrete-time complex valued signal r(n) is oversampled by a factor of two or more. An intermediate signal v(n) is formed from the discrete-time complex valued signal r(n). The intermediate signal v(n) corresponds to the real part of a π/2 frequency shifted version of the obtained discrete-time complex valued signal r(n). A procedure for obtaining an estimate of a frequency dependent mismatch of a two-channel time-interleaved analog-to-digital converter (“TI-ADC”) is applied on the formed intermediate signal v(n). Thereby a TI-ADC mismatch estimate is obtained. The I/Q channel mismatch is estimated and/or compensated based on the obtained TI-ADC mismatch estimate. | 11-19-2015 |
20150358182 | CHANNEL ESTIMATION METHOD AND ASSOCIATED DEVICE FOR ESTIMATING CHANNEL FOR OFDM SYSTEM - A channel estimation method and an associated device for estimating a data channel of a data resource element are provided. The channel estimation method includes obtaining a plurality of pilot channels for pilot resource elements in a time-frequency domain, respectively; utilizing a processing circuit to apply a transformation matrix to the pilot channels, to obtain a plurality of transformed pilot channels corresponding to the pilot resource elements, respectively; and estimating the data channel of the data resource element by performing a plurality of one-dimensional channel estimations according to the transformed pilot channels. | 12-10-2015 |
20150358192 | Determining Frequency Errors in a Multi-Carrier Receiver - Individual multipath components of digital data symbols sent from a transmitter on at least two carrier frequencies generated from a common clock signal, are received ( | 12-10-2015 |
20150365258 | RECEIVER AND RECEPTION METHOD FOR ESTIMATING CHANNEL IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS SYSTEM - A receiver and reception method for estimating a channel in an Orthogonal Frequency Division Multiple Access (OFDMA) system is provided. The receiver includes a delay estimator for estimating, from a signal received from a transmitter through multipaths, at least one of an average time delay of the multipaths and a time delay of one of the multipaths having a maximum power among the multipaths, a rotator for circular-rotating the received signal using the estimated delay, and a channel estimator for estimating a channel impulse response of the circular-rotated signal. | 12-17-2015 |
20160043758 | Distributed Noise Shaping Apparatus - Provided are, among other things, systems, apparatuses methods and techniques for attenuating the level of unwanted noise and/or distortion in a particular frequency band, without similarly attenuating the level of a desired signal in the same frequency band. One such apparatus includes a distributed network comprising a plurality of reactive impedance segments and gain cells that form transmission paths, over which continuous and quantized versions of an input signal propagate before combining with the input signal itself. | 02-11-2016 |
20160065256 | SLIDING INTERMEDIATE FREQUENCY (IF) RECEIVER WITH ADJUSTABLE DIVISION RATIO AND SLIDING IF RECEPTION METHOD - A sliding intermediate frequency (IF) receiver and a sliding IF reception method are provided. A first local oscillation signal and a second local oscillation signal may be generated, based on a division ratio of a frequency of the first local oscillation signal to a frequency of the second local oscillation signal that is determined in advance so that an amount of power to be consumed or an error rate of the sliding IF receiver is optimized. A received input signal may be converted to a first IF signal, based on the first local oscillation signal, and the first IF signal may be converted to a second IF signal, based on the second local oscillation signal. | 03-03-2016 |
20160072533 | Dual Receive Processing In Wireless Communications - A technique, as well as select implementations thereof, pertaining to dual receive processing in wireless communications is described. The technique may involve receiving, by a plurality of receive processing modules, an incoming signal from an antenna to provide a plurality of processing results. The technique may also involve generating, by a determination mechanism, a determination output based on the plurality of processing results. The determination output may include either one or more decoding metrics based on a respective processing result from one of the plurality of receive processing modules or a weighted combination of more than one respective processing result from more than one receive processing module of the plurality of receive processing modules. The technique may further involve decoding, by a decoder, the determination output to provide a decoded signal. | 03-10-2016 |
20160173153 | Interference Cancellation in Microwave Backhaul Systems | 06-16-2016 |
20160380784 | CIRCUIT AND METHOD FOR PERFORMING ADAPTION ON ALL RECEIVER BRANCHES - Receiver circuitry is disclosed that can take circuit branches offline to possibly adapt an offset value. In one embodiment, a circuit in a receiver has at least two branches. Each branch includes an adjustor to adjust the branch signal by an offset value. Selection circuitry takes one of the branches offline by selecting the output of that branch as an offline value, and by selecting the output of one or more of the other branches as a data decision value. The selection circuitry changes which branch is taken offline during the operation of the circuit. When a branch is taken offline, an offset value associated with that branch may be updated, if necessary. | 12-29-2016 |