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EQUALIZERS

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375 - Pulse or digital communications

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Class / Patent application numberDescriptionNumber of patent applications / Date published
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DocumentTitleDate
20120183036METHOD AND RECEIVER FOR ESTIMATING THE CHANNEL IMPULSE RESPONSE USING A CONSTANT MODULUS INTERFERENCE REMOVAL ITERATION - A receiver and associated method estimates a channel impulse response of the communications signal. A communications signal is received as a burst of transmitted symbols, including a known training sequence. The joint estimation of timing offset and initial channel impulse response is determined based on the cross-correlations of the known transmitted symbols and received communications signal. A constant modulus interference removal iteration is applied to improve the initial channel impulse estimation.07-19-2012
20110194597MODULATION ANALYSIS AND DISTORTION IDENTIFICATION - An apparatus, method, computer readable medium, and system are provided to generate a symbol placement associated with a transmission scheme by transforming a retrieved set of equalization coefficients. Symbols included in the symbol placement may be analyzed and quantified in terms of their distance from a decision boundary. Symbols may be synthesized on an iterative basis in order to obtain visibility into the underlying performance of the transmission scheme over time. If equalization is unable to reduce a signal impairment below a threshold value within a predetermined amount of time, then a determination may be made that a non-linear distortion source is present in a network or communication system. Signals received from a plurality of user terminals may be compared with one another in order to determine a probable location or cause of the non-linear distortion.08-11-2011
20130039405COMMUNICATION SYSTEM, TRANSMISSION DEVICE, RECEPTION DEVICE, PROGRAM, AND PROCESSOR - A coding scheme selection unit outputs bits of a signal in a past reception to a second coding unit and outputs bits of a retransmission signal to a third coding unit. The second coding unit decodes bits. The third coding unit codes bits with a different constraint length from a constraint length in the second coding unit.02-14-2013
20130034142SYMBOL TIMING RECOVERY CIRCUIT - Disclosed is a symbol timing recovery circuit which includes an interpolator to generate, using a first filter, interpolation data of an input signal; a forward equalizer to eliminate, using a second filter, a forward interference wave from the input signal based on the interpolation data, and to output the resultant signal after the elimination, a first identification signal, and a first error signal; a backward equalizer to eliminate, using a third filter, a backward interference wave from the input signal based on the interpolation data, and to output the resultant signal after the elimination, a second identification signal, and a second error signal; and a timing recovery unit to generate a tap coefficient of the first filter, based on a tap coefficient of the second filter, a tap coefficient of the third filter, the first identification signal, the first error signal, the second identification signal, and the second error signal.02-07-2013
20100040125RECEPTION OF A SIGNAL TRANSMITTED OVER A TRANSMISSION LINK COMPRISING CODED CHANNELS - A method to receive a signal transmitted over a transmission link comprising coded channels, the method comprising:—equalization operations (02-18-2010
20130083836CONCATENTATION-ASSISTED SYMBOL-LEVEL COMBINING FOR MIMO SYSTEMS WITH HARQ AND/OR REPETITION CODING - Systems and methods are provided for decoding signal vectors in multiple-input multiple-output (MIMO) systems, where the receiver has received one or more signal vectors from the same transmitted vector. The receiver combines the received vectors by vector concatenation The concatenated vector may then be decoded using, for example, maximum-likelihood decoding. In some embodiments, the combined signal vector is equalized before decoding.04-04-2013
20130089131Wireless Transport Framework with Variable Equalizer Training - A system and method for wirelessly transmitting audiovisual information. Training information may be stored in a memory. A plurality of packets may be generated, including the training information. The plurality of packets may also include audiovisual information. The plurality of packets may include first information identifying a first training pattern of a plurality of possible training patterns. The first training pattern may specify one or more locations of the training information in the plurality of packets. The first information may be usable by a receiver to determine the first training pattern of the plurality of possible training patterns. The plurality of packets may be transmitted in a wireless manner.04-11-2013
20120219051Method and Device for Inter-Chip and Inter-Antenna Interference Cancellation - A wireless receiver is constructed to equalize a time-domain received signal, detect a plurality of symbols of the equalized time-domain received signal, and perform interference cancellation on the time-domain received signal. The interference cancellation can be performed using a partial result produced by an IDFT, and may use only neighboring symbols in a detected plurality of symbols. The resulting wireless receiver can be constructed to operate efficiently under a plurality of wireless standards.08-30-2012
20090041106Variable equalizer apparatus - A variable equalizer apparatus for forward and/or reverse equalizers in an amplifier. The system can include a structure to allow continuous contact of the signal flow as an equalizer is removed; jumpers with fixed resistors and associated capacitors and inductors to produce a variable range over many different values; and/or variable resistance potentiometers with fixed resistors and associated capacitors and inductors to produce a variable range over separate value equalizers.02-12-2009
20090296798HSDPA CO-PROCESSOR FOR MOBILE TERMINALS - In one embodiment, an HSDPA co-processor for 3GPP Release 6 Category 8 (7.2 Mb/s) HSDPA that provides all chip-rate, symbol-rate, physical-channel, and transport-channel processing for HSDPA in 90 nm CMOS. The co-processor design is scalable to all HSDPA data rates up to 14 Mb/s. The coprocessor implements an Advanced Receiver based on an NLMS equalizer, supports RX diversity and TX diversity, and provides up to 6.4 dB better performance than a typical single-antenna rake receiver. Thus, 3GPP R6 HSDPA functionality can be added to a legacy R99 modem using an HSDPA co-processor consistent with embodiments of the present invention, at a reasonable incremental cost and power.12-03-2009
20120224620APPARATUS AND METHOD FOR RECEIVING DATA IN A COMMUNICATION SYSTEM - The present invention relates to an apparatus and a method for receiving data using a low-density parity check (LDPC) decoding scheme in a digital broadcasting system. The method comprises calculating a parity check matrix of a trellis coded modulation symbol from data that is received via an antenna; transforming the calculated parity check matrix into a low-density parity check matrix; decoding the data having been received via the antenna, based on the transformed low-density parity check matrix; and recovering the data having been received via the antenna.09-06-2012
20120114031OFDM signal demodulation method and device thereof - The present invention discloses an OFDM signal demodulation method and device thereof. The method comprises: adding a pre-obtained timing offset estimation value of an OFDM signal demodulation device to the initial position of an OFDM symbol of a received signal to obtain a window deviation value of the OFDM symbol; adding a channel time delay extension to the window deviation value to obtain a combined prefix initial position; calculating the combined OFDM signal value starting from the prefix initial position; processing the Fast Fourier Transform (FFT) for the combined OFDM signal value to obtain a frequency domain data subcarrier signal; calculating the frequency domain original channel estimation value processing the channel estimation based on the original channel estimation value phase modification of the OFDM symbol according to the channel estimation compensation indication value; and processing equalization and detection for the frequency domain data subcarrier signal according to the channel estimation result. The present invention uses the cycle prefix of the received signals to promote the demodulation performance of the OFDM signal demodulation device.05-10-2012
20110280298Method and System for Low Complexity Conjugate Gradient Based Equalization in a Wireless System - Methods and systems for processing signals in a receiver are disclosed herein and may include updating a plurality of filter taps utilizing at least one channel response vector and at least one correlation vector, for a plurality of received clusters, based on initialized values related to the at least one channel response vector and the at least one correlation vector. At least a portion of the received signal clusters may be filtered utilizing at least a portion of the updated plurality of filter taps. The update may be repeated whenever a specified signal-to-noise ratio (SNR) for the received signal clusters is reached. The initialized values may be updated during a plurality of iterations, and the update may be repeated whenever a specified number of the plurality of iterations is reached.11-17-2011
20120121003METHODS AND APPARATUS FOR WIRELESSLY COMMUNICATING SIGNALS THAT INCLUDE EMBEDDED SYNCHRONIZATION/PILOT SEQUENCES - An embodiment for wirelessly communicating a signal includes a transmitter combining a plurality of phase shifted input data signals with a plurality of synchronization/pilot sequences to produce a plurality of combined signals, performing frequency domain-to-time domain transformations of the combined signals to produce a plurality of candidate signals, determining peak-to-average ratios for at least some of the plurality of candidate signals, identifying a selected signal from the plurality of candidate signals based on the peak-to-average ratios, and transmitting the selected signal over a wireless communication channel. An embodiment further includes a receiver receiving a channel-affected version of the transmitted, selected signal, determining an estimate of a selective mapping index, which identifies the synchronization/pilot sequence from the plurality of synchronization/pilot sequences, applying corrections to the received signal based on estimated channel perturbations to produce an equalized combined signal, and producing an output data symbol from the equalized combined signal.05-17-2012
20110292990MULTIPLE-INPUT, ON-CHIP OSCILLOSCOPE - An integrated circuit that includes a receive data path is described. The receive data path: equalizes a received analog signal, converts the resulting equalized analog signal to digital data values based on a clock signal, and recovers the clock signal in the digital data values. The integrated circuit also includes an on-chip oscilloscope. The oscilloscope includes: two comparators, a phase rotator that outputs an oscilloscope clock signal whose phase can be varied relative to that of the recovered clock signal, and an offset circuit that outputs a voltage offset. Based on the voltage offset and the oscilloscope clock signal, the comparators output digital values which can be used to determine eye patterns that correspond to the analog signal before and after equalization. The eye patterns can then be correlated with an error rate associated with the received data.12-01-2011
20110292989APPARATUS, SYSTEMS AND METHODS OF SIGNAL COMPENSATION FOR DIFFERENT SIGNALS COMMUNICATED OVER A COAXIAL CABLE SYSTEM - Communication signal compensation systems and methods are operable to compensate communication signals communicated to media devices using an agile equalizer over a coaxial cable communication system. An exemplary embodiment receives a first compensation control signal from a first media device, compensates a received first communication signal based upon the first compensation control signal, communicates the first compensated communication signal to the first media device over the first coaxial cable; receives a second compensation control signal from a second media device, compensates a received second communication signal based upon the second compensation control signal, and communicates the second compensated communication signal to the second media device over the second coaxial cable. The first compensation control signal defines compensation for communication signals communicated over a first coaxial cable. The second compensation control signal defines compensation for communication signals communicated to the second media device over a second coaxial cable.12-01-2011
20090103599DUAL TRANSMISSION STREAM GENERATING DEVICE AND METHOD - A dual transmission stream generating device includes an adaptor to receive a normal stream and to generate an adaptation field in an area of a packet of the normal stream; and a stuffer to generate a packet for a dual transmission stream by stuffing a turbo stream into the adaptation field. Accordingly, the turbo stream and the normal stream can be transmitted efficiently by the generation of the dual transmission stream in various constructions.04-23-2009
20100111156TUNABLE EQUALIZER AND METHODS FOR ADJUSTING THE TUNABLE EQUALIZER - A tunable equalizer with a tunable equalizer frequency response is provided. The tunable equalizer includes an amplifier circuit for amplifying input signals and a tunable circuit coupled to the amplifier circuit. The tunable circuit is arranged to provide a zero point in the equalizer frequency response and the zero point is adjusted according to a controllable value. When the controllable value varies according to a uniform offset, the corresponding zero point varies according to a non-uniform offset.05-06-2010
20100034250IQ imbalance equalization system and method. - Systems and methods for performing channel equalization in a communication system are presented. More particularly, embodiments of the disclosed method and apparatus are directed toward systems and methods for performing channel equalization in an OFDM system. One example of a method of negating the effects of IQ imbalance can include the operations of transmitting a channel estimation string across a channel. The channel estimation string comprises a plurality of known channel estimation symbols. The method further includes logically inverting predetermined symbols within the known channel estimation string; transmitting a second channel estimation string across the channel, the second channel estimation string including the logically inverted predetermined symbols; and estimating the IQ image noise based on received first and second channel estimation symbols.02-11-2010
20090310665Methods and Systems for Digitally Processing Optical Data Signals - Digital signal processing based methods and systems for receiving electrical and/or optical data signals include electrical receivers, optical receivers, parallel receivers, multi-channel receivers, timing recovery schemes, and, without limitation, equalization schemes. The present invention is implemented as a single path receiver. Alternatively, the present invention is implemented as a multi-path parallel receiver in which an analog-to-digital converter (“ADC”) and/or a digital signal processor (“DSP”) are implemented with parallel paths that operate at lower rates than the received data signal.12-17-2009
20090086805APPARATUS FOR, AND METHOD OF, PROCESSING SIGNALS TRANSMITTED OVER A LOCAL AREA NETWORK - Systems for recovering communicated information in a communication system are disclosed and may include at least one digitizer for digitizing an analog received signal comprising the communicated information, thereby creating a digital received signal. The system may include at least one filter for bandwidth-limiting at least a portion of the digital received signal. At least one feed forward equalizer may be used for equalizing at least a portion of the bandwidth-limited signal to create an equalized signal. At least one converter for creating a data signal according to at least the equalized signal. At least one soft decision circuit for creating a soft decision signal according to the data signal. The soft decision circuit may cancel at least a portion of the equalized signal.04-02-2009
20090285275SIGNAL ADJUSTMENT RECEIVER CIRCUITRY - Systems and methods for adjusting a signal received from a communication path are disclosed. A receiver can receive a signal from a communication path which attenuates at least some frequency components of the signal. The receiver can include an equalization block that adjusts at least some of the frequency content of the received signal, a signal normalization block that provides a normalized signal amplitude and/or a normalized edge slope, and a control block. In one embodiment, the control block controls frequency adjustment in the equalization block for high frequencies but not for low frequencies. For low frequency adjustment, the control block controls the normalized signal amplitude in the signal normalization block. In this manner, controlled adjustment for low frequency content is performed in the signal normalization block.11-19-2009
20110206108Method and system for providing a time equalizer for multiline transmission in communication systems - A method and system for multiline transmission in communications systems are described. Eigenvalues are calculated to maximize equalized channel impulse response (08-25-2011
20110268171Signal Selection Apparatus and Method Thereof - A signal selection apparatus for selecting a target signal from a plurality of input signals is provided. The input signals correspond to different time indexes. The signal selection apparatus comprises a weight calculation unit for generating a corresponding weight respectively for each of the input signals, a processing unit for processing the input signals respectively to generate a plurality of processed signals according to the weights, and a selection unit for selecting a signal with a larger energy from the processed signals as the target signal, wherein the weights are used for adjusting an individual energy of the input signals such that the time index of the target signal is earlier within the input signals.11-03-2011
20120294350SIGNAL PROCESSING IN WIRELESS COMMUNICATION RECEIVERS - A method, receiver and program for equalising digital samples of a radio signal received over a wireless communications channel. The method comprises: receiving digital samples of the radio signal; calculating equaliser coefficients in the frequency domain; transforming the equaliser coefficients from the frequency domain to the time domain; and equalising the digital samples in the time domain using the transformed time domain equaliser coefficients.11-22-2012
20080285638Channel equalization in a receiver - A method of estimating a channel response of a channel is provided that includes transforming a frequency domain signal received via the channel into a time domain signal and searching the time domain signal for a location of minimum energy. The method also includes padding the time domain signal with zeroes at the location of minimum energy and transforming the padded time domain signal to a second frequency domain signal. The second frequency domain signal is used as an estimated channel response for the channel.11-20-2008
20080240218Automatic calibration circuit for a continuous-time equalizer - Embodiments of the invention are generally directed to systems, methods, and apparatuses for an automatic calibration circuit for a continuous-time equalizer (CTE). In some embodiments, the calibration circuit separately locks the direct (DC) voltage swing and the alternating (AC) voltage swing of a CTE to reference voltage.10-02-2008
20090190645ADVANCED RECEIVER WITH SLIDING WINDOW BLOCK LINEAR EQUALIZER - A receiver or an integrated circuit (IC) incorporated therein includes a fast Fourier transform (FFT)-based (or hybrid FFT-based) sliding window block level equalizer (BLE) for generating equalized samples. The BLE includes a noise power estimator, first and second channel estimators, an FFT-based chip level equalizer (CLEQ) and a channel monitor unit. The noise power estimator generates a noise power estimate based on two diverse sample data streams. The channel estimators generate respective channel estimates based on the sample data streams. The channel monitor unit generates a first channel monitor signal including truncated channel estimate vectors based on the channel estimates, and a second channel monitor signal which indicates an approximate rate of change of the truncated channel estimate vectors. The FFT-based CLEQ generates the equalized samples based on the noise power estimate, one-block samples of the first and second sample data streams, the channel estimates and the monitor signals.07-30-2009
20110268172RECEIVER APPARATUS AND RECEIVING METHOD - There is disclosed a receiver apparatus that can receive OFDM signals. The apparatus comprises: an FFT unit for transforming signals inputted to the apparatus into frequency-domain signals, thereby outputting the transformed signals on a complex symbol-by-complex symbol basis; correlation-calculating units each of which calculates an index indicating a correlation between complex symbols in a respective one of a plurality of groups, each of the plurality groups being a set of a plurality of complex symbols separated from each other by an interval in which a pilot signal is inserted, the groups being selected such that the complex symbols constituting the groups differing from each other; and a judging unit for determining, based on the calculated index for each group, whether or not any index satisfying a predetermined condition is existent, thereby outputting a result of the judgment.11-03-2011
20110206109System and Method for High Speed Communications Using Digital Signal Processing - Various systems and methods related to equalization precoding in a communications channel are disclosed. In one implementation precoding is performed on signals transmitted over an optical channel. In one implementation precoding and decoding operations are performed in parallel to facilitate high speed processing in relatively low cost circuits. Initialization of the precoders may be realized by transmitting information related to the characteristics of the channel between transceiver pairs.08-25-2011
20110142118APPARATUS AND METHOD FOR EQUALIZING CHANNEL BASED ON CHANNEL ESTIMATION - Provided is a channel equalizing apparatus and method for improving channel equalization performance in an Orthogonal Frequency Division Multiplexing (OFDM) reception system applied to digital broadcasting or a communication system. The apparatus, includes: a channel estimating unit for performing channel estimation by using a pilot signal of a frequency domain; a digital filtering unit for changing a characteristic of a channel in a time domain based on an estimated channel estimation result; and a channel equalizing unit for performing channel equalization of a frequency domain on the signal after changing the channel characteristic.06-16-2011
20080260013Equalization with Selection of Samples - A method is shown for equalizing signals transmitted via at least one transmission antenna and received by at least one reception antenna (10-23-2008
20100177814EQUALIZER AND SEMICONDUCTOR DEVICE - The present invention provides an equalizer and a semiconductor device, that can suppress a decrease in S/N ratio of a reception signal, can facilitate a disconnection test by a direct current signal, and are excellent in reproducibility of a transmission signal. A low-pass filter receives a reception signal supplied from a reception end to output a signal obtained by removing a high frequency component from the reception signal. A subtraction unit subtracts an output signal from the low-pass filter from the reception signal. An addition unit adds the reception signal from the reception end to an output signal from the subtraction unit. Thus, an output signal from the addition unit has a frequency characteristic of emphasizing the high frequency component. Then, an amplifier amplifies the output signal from the addition unit to transmit it to an output end.07-15-2010
20090074048EQUALIZER SYSTEM HAVING A TUNABLE ACTIVE INDUCTOR - An linear equalizer system for a transmission channel includes an active inductor with a tunable inductance and quality factor. The active inductor includes a transconducting element. A current steering digital to analog converter controls the flow of a bias current through the transconducting element to tune the active inductor.03-19-2009
20120195358METHOD AND APPARATUS FOR REDUCING THE PROCESSING RATE OF A CHIP-LEVEL EQUALIZATION RECEIVER - A method and apparatus for reducing the processing rate when performing chip-level equalization (CLE) in a code division multiple access (CDMA) receiver which includes an equalizer filter. Signals received by at least one antenna of the receiver are sampled at M times the chip rate. Each sample stream is split into M sample data streams at the chip rate. Multipath combining is preferably performed on each split sample data stream. The sample data streams are then combined into one combined sample data stream at the chip rate. The equalizer filter performs equalization on the combined sample stream at the chip rate. Filter coefficients are adjusted by adding a correction term to the filter coefficients utilized by the equalizer filter for a previous iteration.08-02-2012
20100232491RECEIVER AND RECEIVING METHOD - A receiver for receiving a signal transmitted through a transmission channel includes an equalizer and a first quality calculator that obtains a first quality value of the received signal. The equalizer includes a first channel estimation unit that estimates a first channel response of the transmission channel from the received signal using a first estimation scheme, and a second channel estimation unit that estimates a second channel response of the transmission channel from the received signal using the second estimation scheme. The equalizer equalizes the received signal using the first or second channel response and outputs the equalized signal. A portion of the second channel estimation unit halts depending on the first quality value.09-16-2010
20090067482Selectable-Tap Equalizer - A signaling circuit having a selectable-tap equalizer. The signaling circuit includes a buffer, a select circuit and an equalizing circuit. The buffer is used to store a plurality of data values that correspond to data signals transmitted on a signaling path during a first time interval. The select circuit is coupled to the buffer to select a subset of data values from the plurality of data values according to a select value. The equalizing circuit is coupled to receive the subset of data values from the select circuit and is adapted to adjust, according to the subset of data values, a signal level that corresponds to a data signal transmitted on the signaling path during a second time interval.03-12-2009
20110044382RECEIVING APPARATUS AND COMMUNICATION SYSTEM - A receiving antenna diversity effect is improved by equalizing the likelihood while exchanging the likelihood among a plurality of equalizers. A receiving apparatus (02-24-2011
20100142604METHOD AND APPARATUS OF FREQUENCY DOMAIN ECHO CANCELLER - A frequency-domain based echo and NEXT canceller is claimed. The canceller uses log06-10-2010
20100226421RECEPTION CIRCUIT, RECEPTION METHOD, AND SIGNAL TRANSFER SYSTEM - A reception circuit includes: an AD converter; an equalization circuit that equalizes an output of the AD converter; a determination circuit to which error information is input from the equalization circuit; and a controller that adjusts at least one of resolution and voltage range of the AD converter, in the circuit the determination circuit outputs a control signal to adjust at least one of resolution and voltage range to the controller based on the error information.09-09-2010
20100195709DEVICE FOR PROCESSING STREAMS AND METHOD THEREOF - A device for processing streams is disclosed. The device includes a stream arranging unit which stacks and rearranges a stream, and a dummy inserting unit which inserts a dummy into the rearranged stream. The device may further include a convolutional interleaver which interleaves the stream with a dummy or an RS encoder and a CRC encoder.08-05-2010
20120243596RECEIVER AND METHOD - A receiver receives data from a sequence of OFDM symbols transmitted via a channel, each OFDM symbol comprising a plurality of data bearing sub-carriers and a plurality of pilot bearing sub-carriers. The receiver includes a channel estimator for estimating the channel and an equaliser for reducing the effects of the channel so that the data can be recovered from the received OFDM symbols. The channel estimator includes a notch processor which is arranged in operation to detect a notch in a received OFDM symbol, the notch providing a plurality of the sub-carriers of the received OFDM symbol within a frequency range which were not transmitted by the transmitter, to determine one or more missing pilot sub-carriers which would have been transmitted within the notch sub-carriers of OFDM symbols according to a pilot sub-carrier pattern, and to generate one or more replacement pilot data symbol for a missing pilot data sub-carrier.09-27-2012
20110150069RF RECEIVER - An RF receiver comprising: an amplifier configured to receive an RF signal over an input bandwidth and to provide an amplified RF signal; an equalizer circuit connected to the amplifier to receive the amplified RF signal and configured to provide an equalized RF signal; a converter module connected to the equalizer circuit and comprising an analog to digital converter configured to convert the equalized RF signal to a digital signal; and a digital signal processing module connected to the receiver module and configured to process the digital signal to provide a plurality of channels at an output of the receiver, wherein the digital signal processing module is further configured to process the digital signal to determine a measure of tilt in the RF signal across the input bandwidth and is connected to the equalizer circuit to provide a control signal for adjusting the measured tilt.06-23-2011
20130070832DIGITAL FREQUENCY DIVIDER - Various embodiments of the present invention relate to systems, devices and method of frequency synthesis that generate in-phase and quadrature-phase clock signals at a programmable frequency. The generated frequency, which can range from a fraction to multiples of the input reference frequency, is generated by dividers following a phase-locked loop, thus avoiding the use of a low input reference frequency as well as frequency doubling.03-21-2013
20090290629Time-Domain Equalizer - The present invention provides a cost-effective TEQ hardware architecture to support multiple VDSL2 profiles. It supports variable TEQ tap length programmable through firmware. Larger TEQ tap length at low-speed profiles is supported by the unique design without adding additional multipliers. The maximum number of TEQ taps supported is actually inversely proportional to the profile frequency. This perfectly meets the requirement to have longer TEQ for low-speed profile and shorter TEQ for high-speed profile.11-26-2009
20110255585METHOD AND APPARATUS FOR SERIAL COMMUNICATION USING CLOCK-EMBEDDED SIGNALS - Apparatus for serial communication using embedded clock signals includes a data divider for dividing a data stream into odd-numbered and even-numbered data streams; a clock-embedded signal generator for generating odd-numbered and even-numbered embedded clock signals by pulse amplitude modulating the odd-numbered and even-numbered data streams and, when an external clock is input, inverting polarities of the pulse amplitude modulated odd-numbered and even-numbered data streams; a clock-embedded signal recovery unit for recovering the odd-numbered and even-numbered data streams by comparing amplitudes of the odd-numbered and even-numbered embedded clock signals with reference voltages, respectively, and recovering synchronization information of the clock by detecting when amplitude polarities of the odd-numbered and even-numbered embedded clock signals are inverted; and a data integrator for integrating the odd-numbered and even-numbered data streams and supplying the result as the data stream.10-20-2011
20110164671RECEIVER DEVICE, INTEGRATED CIRCUIT, RECEIVING METHOD, AND RECEIVING PROGRAM - A wideband carrier frequency error calculator that, for each of a plurality of location patterns, calculates a cumulative value through a predetermined process performed on signals output by an orthogonal transformer for a plurality of sub-carrier positions determined according to a given location pattern while simultaneously shifting the signals output therefrom by one sub-carrier unit along the carrier direction and that also calculates wideband carrier frequency error according to carrier direction discrepancies calculated as maximum values within the cumulative value, and a carrier frequency error corrector that applies corrections to carrier frequency discrepancies according to the wideband carrier frequency error so calculated.07-07-2011
20110261873DIVERSITY RECEIVER FOR PROCESSING VSB SIGNAL - A diversity receiver configured to receive digital signals, including a first modulator configured to receive a first signal and modulate the first signal to first data, a second modulator configured to receive a second signal and modulate the second signal to second data, a path aligner configured to detect starting points of the first data and the second data and generate a control signal for synchronizing the first data and the second data, and an equalizer/decoder configured to synchronize the first and second data and to generate a signal to noise ratio and an equalizer output by a recursive equalization operation for the diversity signals thus synchronized.10-27-2011
20120147942System and Method for Signaling and Detecting in Wireless Communications Systems - A system and method for signaling and detecting in wireless communications systems are provided. A method for processing information includes operating in a first phase, and operating in a second phase in response to determining that a first user is transmitting at a substantially higher power level than a second user, and processing the detected information. The first phase includes iteratively inverting a first filtering operation on received signals, and the second phase includes iteratively inverting a second filtering operation on received signals with consideration given to a first estimation error of symbols of the first user and a second estimation error of symbols of the second user. The operating remains in the first phase in response to determining that the first user is not transmitting at a substantially higher power level than the second user.06-14-2012
20110134986Systems and methods providing in-phase and quadrature equalization - Systems and methods which provide a multimode tuner architecture implementing direct frequency conversion are shown. Embodiments provide a highly integrated configuration wherein low noise amplifier, tuner, analog and digital channel filter, and analog demodulator functionality are provided in a single integrated circuit. A LNA of embodiments implements a multi-path configuration with seamless switching to provide desired gain control while meeting noise and linearity design parameters. Embodiments of the invention implement in-phase and quadrature (IQ) equalization and a multimode channelization filter architecture to facilitate the use of direct frequency conversion. Embodiments implement spur avoidance techniques for improving tuner system operation and output using a clock signal generation architecture in which a system clock, sampling clock frequencies, local oscillator (LO) reference clock frequencies, and/or the like are dynamically movable.06-09-2011
20110134987COMMUNICATION APPARATUS AND COMMUNICATION PROCESS METHOD - Provided is a communication apparatus and a communication process method that improve reception quality when receiving a signal using a plurality of antennas. The communication apparatus includes an RF tuner that receives a wireless signal by the plurality of antennas, a noise amount detection unit that measures the amount of noise of each antenna according to the wireless signal received by the RF tuner, and a time-division timing generation unit that switches a selection of the plurality of antennas by time-division. The time-division timing generation unit periodically switches the plurality of antennas. Further, the time-division timing generation unit makes a selection so that the antenna with the best reception quality has a relatively longer selected period than the other antennas.06-09-2011
20110051794Digital Transmitter - An equalizer provided in a digital transmitter compensates for attenuation in a signal channel to a digital receiver. The equalizer generates signal levels as a logical function of bit history to emphasize transition signal levels relative to repeated signal levels. The preferred equalizer includes an FIR transition filter using a look-up table. Parallel circuits including FIR filters and digital-to-analog converters provide a high speed equalizer with lower speed circuitry. The equalizer is particularly suited to in-cabinet and local area network transmissions where feedback circuitry facilitates adaptive training of the equalizer.03-03-2011
20090175326PARTIAL RESPONSE RECEIVER - A receive circuit for receiving a signal transmitted via an electric signal conductor. A first sampling circuit generates a first sample value that indicates whether the signal exceeds a first threshold level, and a second sampling circuit generates a second sample value that indicates whether the signal exceeds a second threshold level. A first select circuit receives the first and second sample values from the first and second sampling circuits and selects, according to a previously generated sample value, either the first sample value or the second sample value to be output as a selected sample value.07-09-2009
20110305269DEVICE AND METHOD FOR RECEIVER-EQUALIZER CALIBRATION - The disclosure is a device and a method for receiver-equalizer calibration, in which the device includes an adaptive filter, a Clock Data Recovery (CDR) unit, an adaptive control unit and a run length encoding unit. The adaptive filter receives a channel signal, calibrates the channel signal according to a filter control signal and compensates the channel signal to obtain a compensative signal. The CDR unit receives the compensative signal to generate a sampling clock signal, a data signal and a transition sampling signal. The run length encoding unit receives the data signal and run-length encodes the data signal to generate first code data and second code data. The adaptive control unit receives the first code data, the second code data, the data signal and the transition sampling signal, and performs weight calculation to adjust the filter control signal.12-15-2011
20130010853Method and System for Selective Equalization Enablement Based on Modulation Type - Aspects of a method and system for selective equalization enablement based on modulation type are disclosed. One such method includes receiving a signal via an RF channel, detecting a modulation type of the signal, and selecting an equalization circuit for processing the signal based on the modulation type.01-10-2013
20120099636APPARATUS AND METHOD FOR INTERFERENCE CANCELLATION IN MIMO WIRELESS COMMUNICATION SYSTEM - An apparatus and a method for interference cancellation in a Multiple Input Multiple Output (MIMO) wireless communication system. The method for interference cancellation includes equalizing first reception signals received through two or more reception antennas to estimate transmission signals transmitted through two or more transmission antennas, generating two or more second reception signals in which a mutual interference between the transmission signals is removed from the first reception signals by using the estimated transmission signals, independently equalizing the generated two or more second reception signals, and combining the independently equalized two or more second reception signals to estimate a transmission signal in which an interference is removed.04-26-2012
20120099635RECEPTION APPARATUS, RECEPTION METHOD, AND PROGRAM - Disclosed herein is a reception apparatus including a calculation section and a storage section. The calculation section calculates correlation values between a data sequence included in a known signal and a received signal at a given point in time. The storage section has at least an area sufficient for storing the correlation values calculated for one frame using the received signal which is one frame long and to which the known signal is added.04-26-2012
20120114032EQUALIZATION IN PROXIMITY COMMUNICATION - A device includes a semiconductor die having a surface, a plurality of proximity connectors proximate to the surface, and a circuit coupled to at least one of the plurality of proximity connectors. The semiconductor die is configured to communicate voltage-mode signals through capacitive coupling using one or more of the plurality of proximity connectors. The circuit also includes a filter with a capacitive-summing junction to equalize the signals.05-10-2012
20120057625METHOD AND DEVICE FOR TRANSMITTING AND RECEIVING SIGNAL IN WIRELESS COMMUNICATION SYSTEM - The present invention discloses a method and device for transmitting and receiving a signal in a wireless communication system. The method for transmitting a signal in a wireless communication system according to the present invention comprises: receiving an original data block to be transmitted, the length of the original data block being M, wherein M is an integer; disordering the original data block for one or more times, whereby M data symbols in the original data block are rearranged in each of the one or more times of the disordering, so as to obtain one or more disordered data blocks with length of M; cascading the original data block and the one or more disordered data blocks with a cyclic prefix, to form an equalized signal of frequency domain diversity with time-frequency interleaving; and transmitting the equalized signal of frequency domain diversity through a single carrier.03-08-2012
20120027070SYSTEM AND METHOD FOR ITERATIVE NONLINEAR COMPENSATION FOR INTERMODULATION DISTORTION IN MULTICARRIER COMMUNICATION SYSTEMS - A receiver is provided that can receive a first signal transmitted on a first carrier and a second signal transmitted on a second carrier. The receiver includes a channel estimation portion, a multicarrier nonlinear equalizer, a first log likelihood computing portion and a second log likelihood computing portion. The channel estimation portion can output a first estimation. The multicarrier nonlinear equalizer can output a first equalized signal and a second equalized signal. The first log likelihood ratio computing portion can output a first log likelihood ratio signal based on the first equalized signal. The second log likelihood ratio computing portion can output a second log likelihood ratio signal based on the second equalized signal. The multicarrier nonlinear equalizer can further output a third equalized signal and a fourth equalized signal. The third equalized signal is based on the first signal, the second signal and the first estimation. The fourth equalized signal is based on the first signal, the second signal and the first estimation.02-02-2012
20120063502DIGITAL BROADCAST TRANSMITTER, DIGITAL BROADCAST RECEIVER, AND METHODS FOR CONFIGURING AND PROCESSING STREAMS THEREOF - A method for processing a stream of a digital broadcast transmitter, the digital broadcast transmitter, a method of processing a stream of a digital broadcast receiver, and the digital broadcast receiver are provided. The method includes: configuring a stream including a slot to which mobile data is allocated; and encoding and interleaving the configured stream and outputting the encoded and interleaved stream. Each slot of the stream includes signaling data, and the signaling data includes a slot indicator indicating a type of a slot, and may include at least one of a backward training indicator and a forward training indicator according to a value of the slot indicator. Accordingly, information on an adjacent slot is efficiently used.03-15-2012
20090135894SIGNAL RECEIVING CIRCUIT UTILIZING TIMING RECOVERY PARAMETER GENERATING CIRCUIT - A signal receiving circuit includes: a sampler, for receiving an analog signal and sampling the analog signal according to a sampling clock to generate a sampling signal; an ADC, coupled to the sampler, for converting the sampling signal to a digital signal; an equalizer, coupled to the ADC, for equalizing the digital signal to generate an equalized digital signal; a quantizer, coupled to the equalizer for quantizing the equalized digital signal to generate a processed digital signal; and a timing recovery circuit, directly connected to the output terminal of the sampler and coupled to the quantizer, for adjusting the timing of the sampling clock according to the processed digital signal and the digital signal. Timing recovery parameter generating circuits are also disclosed.05-28-2009
20110103453OFDMCHANNEL ESTIMATION SYSTEM AND METHOD COMPONENTS - Channel estimation for high mobility OFDM channels is achieved by identifying a set of channel path delays from an OFDM symbol stream including carrier data, inter-channel interference noise and channel noise; determining the average channel impulse response for the identified set of channel path delays in each symbol; generating a path delay curvature for each channel path delay in each symbol based on stored average channel impulse responses for the identified channel path delays; estimating the carrier data in the symbols in the OFDM symbol stream in the presence of inter-channel interference noise and channel noise from the OFDM symbol steam and the average impulse responses for the identified channel path delays; reconstructing the inter-channel interference noise in response to the path delay curvature, the identified set of channel path delays and estimated carrier data to produce a symbol stream of carrier data and channel noise with suppressed inter-channel interference noise.05-05-2011
20120314753Equalizer with Controllably Weighted Parallel High Pass and Low Pass Filters and Receiver Including Such an Equalizer - An adjustable equalizer that includes a first branch including a low pass filter (LPF) typically having a variable gain (β), and a second branch including a high pass filter (HPF) typically having another variable gain (α). Outputs of the branches in response to an input signal are summed to produce an equalized output. The equalizer can be implemented using CMOS technology and can be capable of equalizing an input indicative of data having a maximum data rate of at least 1 Gb/s. Typically, the equalizer is embodied in a receiver for use in equalizing a signal, indicative of video or other data, that has propagated over a serial link to the receiver.12-13-2012
20120314751Channel Estimation In A Multi-User MIMO-OFDM System In The Presence Of User Terminal Symbol-Specific Phase Offsets - Disclosed is an OFDM wireless communication system comprising an access point, and a plurality of remote user terminals. The access point receives one or more training symbols transmitted by the user terminals, each training symbol comprising pilot symbols associated with phase offset estimation OFDM sub-carriers of said training symbol, the phase offset estimation sub-carriers comprising subsets of sub-carriers associated with respective user terminals, wherein each subset is used exclusively by the associated user terminal during channel estimation, and further symbols associated with channel estimation OFDM sub-carriers of said training symbol, wherein the channel estimation sub-carriers are used by all user terminals. The access point estimates, for each user terminal, symbol-specific phase offsets specific to the user terminal using the received pilot symbols associated with the user specific subset of the phase offset estimation sub-carriers; and estimates the uplink channel using the user-terminal-symbol-specific phase offset estimates and the received further symbols.12-13-2012
20120314752MULTI-USER DETECTION USING EQUALIZATION AND SUCCESSIVE INTERFERENCE CANCELLATION - A method and apparatus for multi-user detection is disclosed. A signal is received in a shared spectrum, and samples of the received signals are produced as a received vector. The received vector is segmented into vector segments. Each segment has a portion that overlaps with another segment and the overlapping portion includes at least one chip less than twice a channel impulse response length. For each vector segment, symbols are successively determined for communications by determining symbols for a communication in the communications, ordering the communications by received power and removing a contribution of the communication from the vector segment. The determining of symbols includes equalizing an input vector corresponding to a segment of the received vector using fast Fourier transform. The determined symbols are assembled into a data vector for each communication in the communications.12-13-2012
20120314750Apparatus and Method for Selective Single-Carrier Equalization - Embodiments of an apparatus and method for selective SC equalization are provided. Multipath propagation in a communication channel often changes, and the severity of multipath propagation is often below worst case conditions supported by a SC communication device. When multipath propagation is less severe and below worst conditions, the use of FDE in a SC receiver to mitigate ISI can be overkill and can result in excess power being consumed. The excess power consumption can be attributed to the general inability of the structure used to perform FDE to scale in terms of performance with channel conditions. Embodiments of the apparatus and method for performing selective equalization in a SC receiver allow either FDE or TDE to be performed based on the current multipath propagation conditions of a communication channel. In general, TDE is used in place of FDE to conserve power when channel conditions permit.12-13-2012
20100091829OPTIMISED ARCHITECTURE FOR A DOWNSAMPLING FIR FILTER - An apparatus for generating filtered and downsampled data comprises a calculation unit, a polyphase addition unit and a downsampling unit operable in a data decimation phase and a data preserving phase. The calculation unit is arranged to receive input data and is configured to generate a first data part during the data decimation phase and a second part during the data preserving phase. The polyphase addition unit is configured to generate a third data part in dependence on said first and second data parts and to output said third data part to the downsampling unit.04-15-2010
20100246656Methods and systems for soft-bit demapping - Methods and systems for reconfigurable soft-output bit demapping, reconfigurable for different modes of operation (i.e., different transmitter/receiver configurations) and for different modulation schemes are provided. In an embodiment, a reconfigurable soft-output bit demapping system includes a mode/modulation independent equalizer, a plurality of mode/modulation independent soft-slicers coupled to the outputs of the equalizer, a plurality of mode/modulation independent post-scalers coupled to the outputs of the soft-slicers, and a mode-dependent coefficient calculator. The coefficient calculator generates parameters for configuring the equalizer, the soft-slicers, and the post-scalers according to the used mode of operation and modulation scheme.09-30-2010
20090060016METHOD OF ESTIMATING INTER-CARRIER INTERFERENCE (ICI) AND ICI MITIGATING EQUALIZER - An inter-carrier interference (ICI) mitigating equalizer includes a channel estimator, a channel calculator, an ICI estimator, a subtracter, and an equalizer. The channel estimator estimates a channel response from a received signal, and the channel calculator calculates a basic component of a channel response and fluctuating components of the channel response from the estimated channel response. The ICI estimator multiplies the fluctuating components of the channel response by a received signal in a frequency domain, filters the multiplication results according to filter coefficients, and estimates an ICI component included in the received signal based on the filtering results. The subtracter subtracts the ICI component from the received signal in the frequency domain. The equalizer equalizes an output signal of the subtracter based on the basic component of the channel response.03-05-2009
20090060017Selectable-Tap Equalizer - A signaling circuit having a selectable-tap equalizer. The signaling circuit includes a buffer, a select circuit and an equalizing circuit. The buffer is used to store a plurality of data values that correspond to data signals transmitted on a signaling path during a first time interval. The select circuit is coupled to the buffer to select a subset of data values from the plurality of data values according to a select value. The equalizing circuit is coupled to receive the subset of data values from the select circuit and is adapted to adjust, according to the subset of data values, a signal level that corresponds to a data signal transmitted on the signaling path during a second time interval.03-05-2009
20120076191Apparatus and method to process signals from one or more transmission sources - A receiver and a method to process signals from one or more transmission sources. The receives includes a front-end having: an input coupling path to route an analog input signal received from one or more transmission sources; an equalizer to generate an equalized signal from the analog input signal; and an ADC to generate a digitized signal from the equalized signal. The method includes routing the analog input signal through an input coupling path; equalizing the analog input signal to generate an equalized signal therefrom; and digitizing the equalized signal to generate a digitized signal therefrom.03-29-2012
20090046772METHOD AND APPARATUS FOR CARRIER POWER AND INTERFERENCE-NOISE ESTIMATION IN SPACE DIVISION MULTIPLE ACCESS AND MULTIPLE-INPUT/MULTIPLE-OUTPUT WIRELESS COMMUNICATION SYSTEMS - Estimates of carrier signal power S and interference-noise NI at the output of the equalizer in a wireless communication system is obtained by (i) determining the variance, σ02-19-2009
20120189045Signaling with Superimposed Clock and Data Signals - A data receiver circuit includes an interface to receive an input signal that includes a data signal and a clock signal superimposed on the data signal. The data signal has an associated symbol rate and an associated symbol period equal to the reciprocal of the associated symbol rate. The clock signal has a frequency N times the associated symbol rate, where N is an integer. A phase-locked loop (PLL) coupled to the interface extracts the clock signal from the input signal to provide an extracted clock signal. A phase interpolator adjusts the phase of the extracted clock signal to provide a phase-adjusted extracted clock signal. A sampling circuit samples the data signal at a sampling point. The sampling circuit is synchronized to the phase-adjusted extracted clock signal.07-26-2012
20120230381TRANSCEIVER SYSTEM AND ASSOCIATED METHODS AND SYSTEMS - In the example embodiments, test signals sent from a transmitting system are received at a receiving system. The receiving system generates a determination signal indicating, in one embodiment, whether received signals have a desired relationship with respect to a clock signal at the receiving system. Timing of the clock signal or timing for transmitting signals may be adjusted based on the determination. In another embodiment, the receiving system generates a determination signal indicating whether the pulse width of a lone pulse signal equals a desired time interval. Equalization or pre-emphasis is controlled based on the determination signal.09-13-2012
20120230382SYSTEMS AND METHODS FOR PROVIDING INTEGRATED FINANCIAL CALCULATIONS AND ACTION PLANS - A baseband-derived RF predistortion system using a lookup table having coefficients extracted at baseband and then applied at RF by means of a vector modulator. The architecture combines the narrowband advantage of envelope predistortion with the accuracy of baseband predistortion, and including compensation for memory effects. A polynomial-based alternative is also described.09-13-2012
20110002374RECEIVER CIRCUIT, METHOD OF ADJUSTING OFFSET, AND TRANSMISSION/RECEPTION SYSTEM - A receiver circuit includes: an equalization circuit that equalizes a first signal to obtain a second signal, and adjusts a characteristic of an equalization in accordance with an error between the second signal and a third signal; and a first offset adjustment circuit that adjusts an offset of the first signal in accordance with an error signal indicating the error.01-06-2011
20120087404Calibrating Received Signal Measurements in a Communication Device - Received signal measurements are calibrated in a communication device by measuring a received signal level for each of one or more subcarriers of a transmitted signal received from another communication device, converting the measured received signal level for each of the one or more subcarriers into a corresponding measured power level, estimating a terminal-to-terminal impedance between the communication devices and calculating a corrected power level for each of the one or more subcarriers as a function of the measured power level for the subcarrier, a known reference input impedance for the communication device and the estimated terminal-to-terminal impedance.04-12-2012
20110299582Method and Apparatus for Performing Channel Equalization on a MIMO Signal - A method is provided for performing channel equalization on a wireless signal. The method includes: (i) formulating an equalizer associated with sub-carriers of the wireless signal, wherein the equalizer is a function of a quantity relating to signal quality (12-08-2011
20120140811RECEPTION CIRCUIT - A reception circuit includes: a sampling circuit to sample an input data signal based on a clock signal and output a sampled signal; a data interpolation circuit to interpolate the sampled signal based on phase information corresponding to the sampled signal and output an interpolated data signal; an interpolation error decision circuit to output an interpolation error based on the sampled signal and the phase information; a decision/equalization circuit to equalize the interpolated data signal using an equalization coefficient set based on the interpolation error, to check an equalized interpolated data signal and to output a checked signal; and a phase detection circuit to generate the phase information based on at least one of the checked signal and the equalized interpolated data signal and output the phase information to the data interpolation circuit and the interpolation error decision circuit.06-07-2012
20120243597Upstream frequency response measurement and characterization - Upstream frequency response measurement and characterization. Signaling is provided between respective communication devices within a communication system. Based upon at least one of these signals, one of the communication devices captures a number of sample sets corresponding thereto at different respective frequencies (e.g., a different respective center frequencies, frequency bands, etc.). Then, spectral analysis is performed with respect to each of the sample sets to generate a respective and corresponding channel response estimate there from. After this number of channel response estimates is determined, they are combined or splice together to generate a full channel response estimate. In implementations including an equalizer, different respective sample sets may correspond to those that have undergone equalization processing and those that have not.09-27-2012
20080240219Methods And Circuits For Performing Margining Tests In The Presence Of A Decision Feedback Equalizer - Described are methods and circuits for margin testing receivers equipped with Decision Feedback Equalization (DFE) or other forms of feedback that employ historical data to reduce intersymbol interference (ISI). In one example, a high-speed serial receiver with DFE injects the correct received data (i.e., the “expected data”) into the feedback path irrespective of whether the receiver produces the correct output data. The margins are therefore maintained in the presence of receiver errors, allowing in-system margin tests to probe the margin boundaries without collapsing the margin limits. Some receivers include local expected-data sources that either store or generate expected data for margin tests. Other embodiments derive the expected data from test data applied to the receiver input terminals.10-02-2008
20130170534SUCCESSIVE INTERFERENCE CANCELLATION SYSTEM AND METHOD FOR MIMO HORIZONTAL ENCODING AND DECODING - A method and system for receiving and decoding horizontally encoded MIMO-OFDM transmissions with improved efficiency. In one embodiment, MIMO decoding is performed on each of the extracted separate tones of a MIMO-OFDM signal to extract and demodulate frequency domain symbols of the first layer corresponding to one or more code blocks. For each code block of the first layer that passes an error check, corresponding portions of the second layer are decoded using SIMO decoding.07-04-2013
20130170535RECEIVER AND RECEIVING METHOD FOR HIERARCHICAL MODULATION IN SINGLE FREQUENCY NETWORKS - A receiver recovers local service data symbols from first Orthogonal Frequency Division Multiplexed (OFDM) symbols in the presence of second OFDM symbols. The second OFDM symbols carry national broadcast data symbols and modulated on to the sub-carriers of the second OFDM symbols using a first modulation scheme. The first OFDM symbols carry the national broadcast data symbols and the local service data symbols from a local insertion pipe and modulated on to the sub-carriers of the first OFDM symbols using a second modulation scheme. The receiver comprises an OFDM detector which includes an equalizer to recover local service modulated sub-carriers of the second modulation scheme.07-04-2013
20080225935Method and architecture for digital pulse shaping and rate conversion - A method and architecture for pulse shaping are provided. The architecture includes a pulse shaping filter having a plurality of memory elements and a plurality of taps connected to the plurality of memory elements wherein a total number of the plurality of taps is independent of a sampling rate. The pulse shaping filter further includes a selector configured to select outputs from the plurality of taps to define a pulse shaped output.09-18-2008
20130177063Digital Phase Equalizer for Serial Link Receiver and Method Thereof - An apparatus of automatic power control for burst mode laser transmitter and method are provided. In one implementation a method includes: pushing a first multi-bit data into a data memory; modifying the data memory to remove a condition of frequent transition in the data memory, if the condition of frequent transition is found; establishing a list of indices pointing to data transition of the data memory; and sequentially examining a respective run length of the data indexed by each entry in the list, modifying the associated data to lengthen the respective run length if the respective run length is too short, modifying the associated data to shorten the respective run length if the respective run length is too long, and outputting a second multi-bit data by taking data from the data memory.07-11-2013
20130128942ADVANCED INTERFERENCE CANCELLATION FOR PRECODED GSM EDGE RADIO ACCESS NETWORK (GERAN) - An interference cancellation receiver for a pre-coded orthogonal frequency division multiplexed (OFDM) based system combines temporal interference cancellation within the OFDM framework. Multi-path equalization and inter-symbol interference (ISI) cancellation are performed on a time domain channel estimate of a received signal. An output from the multi-path equalization is transformed to the frequency domain. Inter-channel interference (ICI) is performed in the frequency domain on an equalized signal from the multi-path equalization after transforming the equalized signal from the time domain to the frequency domain.05-23-2013
20080198911Equalizer for Single Carrier FDMA Receiver - A method of equalizing a received signal compensates for frequency selectivity of the communication channel taking into account channel estimation errors. The method comprises generating channel estimates for the received signal, computing filter weights for an equalizer based on said channel estimates and a covariance of the channel estimation error, and filtering the received signal using the computed filter weights.08-21-2008
20100316107FREQUENCY DOMAIN EQUALIZATION METHOD FOR CONTINUOUS PHASE MODULATED SIGNALS - A method for frequency domain equalization of a cyclic CPM signal received via a channel is disclosed. In one aspect, the method includes representing the received cyclic CPM signal as a matrix model comprising a channel matrix representing influence of the channel, separate from a Laurent pulse matrix and a pseudocoefficient matrix respectively representing Laurent pulses and pseudocoefficients determined by Laurent decomposition of the received cyclic CPM signal. The method may further include applying a channel equalizer on the separate channel matrix and after the equalization. It may further include demodulating the received cyclic CPM signal by the matrix model, the demodulation exploiting known correlation properties of the Laurent pulses and the pseudocoefficients.12-16-2010
20130156085PHASED ARRAY DEVICE AND CALIBRATION METHOD THEREFOR - The calibration method, performed on a phased array device including channel elements coupled in parallel by a transmission line, has the steps of: obtaining channel responses corresponding to the channel elements through the transmission line, and each of the channel responses is obtained when one of the channel elements is turned on, and the rest of the channel elements are turned off; calculating a characteristic value corresponding to the transmission line based on the obtained channel responses of the channel elements; and adjusting a channel parameter of one of the channel elements based on the characteristic value of the transmission line.06-20-2013
20120281746DEVICE AND METHOD FOR IDENTIFICATION AND CANCELLATION OF CROSSTALK - Devices and methods for the cancellation for and identification of crosstalk for different application cases, particularly for near-end crosstalk (NEXT), are known. Too little attention is paid to the situation of non-reciprocally coupled systems. Therefore, devices and methods for cancellation and identification of far-end crosstalk (FEXT), which enable a reliable identification of an unknown system, are lacking in practice.11-08-2012
20110280297Direct Digital Conversion Tuner - A direct sampling tuner includes a low noise amplifier and an optional dynamically configurable band pass filter coupled to the low noise amplifier. The optional filter is configured to pass a selected band of channels. The tuner further includes a relatively high accuracy, multi-bit analog-to-digital converter (“ADC”) coupled to the LNA or to the optional dynamically configurable band pass filter. The ADC operates at greater than about twice a frequency of a sampled signal. The ADC directly samples the spectrum of the selected channels at the Nyquist rate, thus avoiding image problems presented by conventional tuners.11-17-2011
20110310949High-Speed Signaling Systems with Adaptable Pre-Emphasis and Equalization - A signaling system includes a pre-emphasizing transmitter and an equalizing receiver coupled to one another via a high-speed signal path. The receiver measures the quality of data conveyed from the transmitter. A controller uses this information and other information to adaptively establish appropriate transmit pre-emphasis and receive equalization settings, e.g. to select the lowest power setting for which the signaling system provides some minimum communication bandwidth without exceeding a desired bit-error rate.12-22-2011
20110310948LOW-COMPLEXITY DIVERSITY USING PREEQUALIZATION - A diversity receiver includes a first RF front end module for receiving a first RF signal, and frequency converting the first RF signal and outputting a first diversity signal, a second RF front end module for receiving a second RF signal, frequency converting the second RF signal and outputting a second diversity signal, a first converter for converting the first diversity signal to a first time-domain signal, a second converter for converting the second diversity signal to a second time-domain signal, a first transformer for translating the first time-domain signal to a first frequency-domain signal, a second transformer for translating the second time-domain signal to a second frequency-domain signal, a first pre-equalizer for equalizing the first frequency-domain signal, a second pre-equalizer for equalizing the second frequency-domain signal, and a combiner for combining the first and second pre-equalized frequency-domain signals. The diversity receiver further includes a channel estimator having a mirror window.12-22-2011
20110310947METHOD AND APPARATUS FOR PERFORMING ADAPTIVE EQUALIZATION - Systems and techniques for adapting and/or optimizing an equalizer of a receiver are described. The equalizer's behavior can be adjusted by modifying one or more equalization parameters. At the beginning of the adaptation and/or optimization process, the system can determine robust initial values for the one or more equalization parameters. The system can then adapt and/or optimize the equalizer by iteratively adjusting the one or more equalization parameters. Specifically, in each iteration, the system can use the receiver's clock and data recovery (CDR) circuitry to determine the number of early and late data transitions associated with one or more data patterns. Next, the system can adjust the one or more equalization parameters so that, for each data pattern in the one or more data patterns, the ratio between the number of early data transitions and the number of late data transitions is substantially equal to a desired value.12-22-2011
20130188679COMMUNICATION SYSTEM HAVING DATA-DEPENDENT SUPERIMPOSED TRAINING MECHANISIM AND COMMUNICATION METHOD THEREOF - The present invention discloses a communication system with a data-dependent superimposed training mechanism and a communication method thereof. The system uses a precoding module installed in front of the data-dependent superimposed training mechanism to precode data by a precoding matrix. The precoding matrix is a N×N unitary matrix, which is constructed by Q×Q precoding sub-matrix. Q is the block size N divided by the channel length. The precoding matrix can achieve full frequency diversity. Any two sets of data precoded by the precoding matrix must be different from each other, such that the receiver can effectively identify the data transmitted from the transmitter and the computational complexity of the receiver is reduced.07-25-2013
20130114661WIRELESS COMMUNICATION RECEIVER WITH PHASE NOISE ESTIMATION AND PHASE NOISE COMPENSATION PERFORMED AFTER CHANNEL ESTIMATION, AND RELATED WIRELESS COMMUNICATION RECEIVING METHOD AND PHASE NOISE COMPENSATION APPARATUS - A wireless communication receiver includes a first signal processing block, a phase noise compensation apparatus, and a second signal processing block. The first signal processing block is arranged for generating a first processed output by processing a reception signal, wherein the first signal processing block includes a channel estimation unit arranged for performing channel estimation. The phase noise compensation apparatus is arranged for receiving the first processed output and generating a second processed output by performing phase noise compensation according to the received first processed output. The second signal processing block is arranged for receiving the second processed output and processing the received second processed output.05-09-2013
20130195165GROUND REFERENCED SINGLE-ENDED SIGNALING - One embodiment of the present invention sets forth a mechanism for transmitting and receiving ground-referenced single-ended signals. A transmitter combines a direct current (DC) to DC converter including a flying capacitor with a 2:1 clocked multiplexer to drive a single-ended signaling line. The transmitter drives a pair of voltages that are symmetric about the ground power supply level. Signaling currents are returned to the ground plane to minimize the generation of noise that is a source of crosstalk between different signaling lines. Noise introduced through the power supply is correlated with the switching rate of the data and may be reduced using an equalizer circuit.08-01-2013
20130208777TRANSMISSION STREAM GENERATING DEVICE FOR GENERATING TRANSMISSION STREAM WHICH ADDITIONAL DATA IS STUFFED IN A PAYLOAD AREA OF A PACKET, DIGITAL BROADCAST TRANSMITTING/RECEIVING DEVICE FOR TRANSMITTING/RECEIVING THE TRANSMISSION STREAM, AND METHODS THEREOF - A transmission stream (TS) generating apparatus includes an adaptor which receives general data and generates a stream having a plurality of packets, and which provides adaptive field in some of the plurality of packets, and an inserter which inserts additional data into all the payload areas of some of the plurality of packets that are not provided with the adaptive fields. Because additional data is transmitted, without requiring adaptive field header in certain packet, a data transmission rate is increased.08-15-2013

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