Abstract: A method comprises performing a first pass test over a plurality of sets of equalization coefficients to filter the plurality of sets of equalization coefficients to produce one or more filtered sets of equalization coefficients. Each filtered set of equalization coefficients meets a first predetermined threshold. The method also comprises performing a second pass test over the one or more filtered sets of equalization coefficients to determine a final set of equalization coefficients that meets a second predetermined threshold. The second pass test produces more accurate results than the first pass test.

Abstract: A method of estimating the Doppler spread of a communication channel includes computing a first sum defined by a difference between the pilot tones of a first group of N symbols and a corresponding pilot tones of a second group of N symbols preceding the first group of N symbols, computing a second sum defined by the pilot tones of the second group of N symbols, and computing a ratio of the first sum and the second sum for each of the N symbols of the first and second group of symbols to generate N ratios representative of the Doppler spread of the channel. The first sum is further defined by the square of the difference between the pilot tones of the first group of N symbols and the corresponding pilot tones of the second group of N symbols.

Abstract: A reception apparatus includes: a Fourier transform unit to output a converted signal; a propagation path estimation unit to calculate propagation-path-estimated-values based on pilot subcarriers; and a propagation path compensation unit, including a filter, to compensate propagation path distortion, the filter includes: first multipliers to multiply the propagation-path-estimated-values of taps other than a center tap by filtering coefficients; a first adder to add outputs of the first multipliers; a first subtractor to calculate an error between an output of the first adder and a propagation-path-estimated-value of the center tap; a filtering coefficient generation unit to generate the filtering coefficients based on the error; a second multiplier to multiply the propagation-path-estimated-value of the center tap by first coefficient; a third multiplier to multiply the output of the first adder by second coefficient; and a second adder to add an output of the second multiplier and an output of the third mul

Abstract: An apparatus comprising a memory and a processor coupled to the memory, wherein the memory includes instructions that when executed by the processor cause the apparatus to perform the following receive an incoming signal at a sampling rate that is greater than a symbol rate associated with the incoming signal, replicate a plurality of data streams from the incoming signal, apply a plurality of fractional delays for the data streams, and perform an adaptive equalization on a plurality of data blocks generated from the data streams, wherein the fractional delay is applied to the data streams independently of the adaptive equalization, and wherein the adaptive equalization implements taps spaced at a fraction of a symbol interval associated with the incoming signal.

Abstract: The present invention relates to utilization of sampling rate at the receiver that is below the symbol rate of a bandwidth constrained communication system. Furthermore, if the appropriate up-sampling technique is used, the method avails full retrieval of the information from the under sampled received signal.

Abstract: An integrated circuit equalizes a data signal expressed as a series of symbols. The symbols form data patterns with different frequency components. By considering these patterns, the integrated circuit can experiment with equalization settings specific to a subset of the frequency components, thereby finding an equalization control setting that optimizes equalization. Optimization can be accomplished by setting the equalizer to maximize symbol amplitude.

Abstract: Forward and backward filters in cascade establish a specified phase shift in audio or video signals. The backward filter applies its filtering in a backward direction to impart a phase shift to its backward-filtered output that is a function of frequency. The forward filter applies its filtering in a forward direction to impart a phase shift to its forward-filtered output that has the specified phase shift relative the phase shift of the backward filter. Preferably, the two filters are recursive and are applied to signals that represent overlapping segments of the audio or video information. The overlap interval is used for filter initialization.

Abstract: A method and apparatus is disclosed to compensate for interference and/or distortion impressed onto a transmitted communication signal in the presence of one or more time-varying noise and/or interference conditions. A communications receiver includes a noise analyzer to characterize the composition of the interference and/or the distortion and produce a selection signal indicating the composition of the interference and/or the distortion. The communications receiver selects at least one set of equalization coefficients and/or updates at least one parameter of a least-squares algorithm or the suitable equivalent algorithm to compensate for the interference and/or the distortion impressed onto a transmitted communication signal in the presence of a particular time-varying noise and/or interference condition.

Abstract: 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.

Abstract: An apparatus including a receiver having a feed forward equalizer (FFE) coupled to a communication channel. The receiver may be configured to adjust the FFE using information based on an estimate of one or more characteristics of the communication channel.

Abstract: Provided is a data transmission apparatus to transmit a reference orthogonal frequency division multiplexing (OFDM) symbol generated by frequency division multiplexing a reference symbol and a data symbol, and a data reception apparatus to estimate a channel using the reference OFDM symbol. Since the reference symbol and the data symbol are frequency division multiplexed, a Peak to Average Power Ratio (PAPR) may not increase greatly, and the transmission apparatus may transmit the reference OFDM symbol to the data reception apparatus more frequently. Accordingly, the data reception apparatus may estimate a channel accurately.

Abstract: An OFDM communication system performs time domain channel estimation responsive to received symbols before the symbols are processed by a fast Fourier transform. The communication system generates virtual pilots from actual pilots to improve the stability and quality of channel estimation. The system generates a reference signal from the actual and virtual pilots and correlates the resulting reference signal with a signal responsive to the received symbol to generate an initial channel impulse response (CIR) and to determine statistics about the channel. In some circumstances, the resulting reference signal is correlated with a modified symbol in which the actual and virtual pilot locations are emphasized and the data locations are deemphasized. Time domain channel estimation iteratively improves on the initial CIR. The system determines channel estimates for data only symbols through averaging such as interpolation.

Abstract: A reception device includes two antennas 1-1, 1-2 that are in an inverse correlation, a switching unit 4 which switches the signal that is to be processed among signals received by the two antennas 1-1, 1-2, and an adaptive equalizer 6 which uses equalization coefficients to perform equalizing processing on the signal considered by the switching unit 4 to be the signal to be processed, and an equalization coefficient altering unit 7 which alters the equalization coefficients used by the adaptive equalizer 6 synchronously with the timing of switching performed by the switching unit 4. In the reception device can reduce the required time for reconvergence of equalization coefficients stemming from reception system switching in selection diversity using an inverse correlation antenna.

Abstract: The present invention provides a data stream processing method, device, and system. The data stream processing method includes: using a precoding parameter to perform precoding processing on an lth to-be-sent data stream of a current kth transmitting device, where the lth to-be-sent data stream includes a lattice point data stream mapped to a lattice grid; and sending the precoded lth to-be-sent data stream to a kth receiving device, where both l and k are positive integers. The technical solutions in the embodiments of the present invention can be helpful for filtering out interference, exactly complies with an actual processing procedure of an interfering data stream, and have strong practicability.

Abstract: A receiver circuit receives an incoming signal and accordingly provides an internal signal, and includes an equalizer, a slicer module and a counter module. The equalizer provides a signal level according to the incoming signal, the slicer module compares if the internal signal exceeds a level range; according to comparison result, the counter module provides a signal quality indication capable of indicating whether a bit error rate of signal receiving is greater than a predetermined reference bit error rate. One of an upper bound and a lower bound of the level range can equal the signal level, a distance between the upper bound and the lower bound is set according to a reference signal-to-noise ratio which associates with the reference bit error rate.

Abstract: An unrolled decision feedback equalizer (DFE) as disclosed herein has a reduced number of compensation factors while keeping a suitable performance level for a given application. The KN possible DFE correction levels are reduced or compressed into fewer levels (R), merging together the levels that are the closest together where K represents the number of possible symbols in each baud, or the number of bits encoded into each baud, and N represents the DFE depth in number of bauds. A mapping function is then provided to convert the KN combinations of previous history bits into R sampler selections.

Abstract: Frequency domain based methods and systems to perform adaptive multi-mode pre-decoding linear equalization, adaptive channel estimation, turbo equalization, turbo equalization iteration control, and noise variance estimation. An adaptive linear pre-decoder equalizer may include a multi-mode equalizer, which may include a blind equalizer to determine initial equalization coefficients and a decision-directed equalizer to refine the initial equalization coefficients. Turbo equalization may include a dynamic iteration termination criterion and/or a fixed termination criterion. Turbo equalization may be based in part on an adaptive estimated noise variance. Methods and systems disclosed herein may be implemented with respect to single-carrier signals such as digital video broadcast signals.

Abstract: A method and a circuit for controlling an equalizer and an equalizing system are disclosed. The method includes providing a first level from a set of levels as a peaking level of the equalizer; equalizing a transmission signal by using the equalizer with the first level to obtain a first signal; providing a second level from the set of levels as the peaking level of the equalizer; equalizing the transmission signal by using the equalizer with the second level to obtain a second signal; determining a first frequency of the first signal; determining a second frequency of the second signal; comparing the first frequency and second frequency to obtain a comparing result; and determining the peaking level of the equalizer for following equalization of the transmission signal in accordance with the comparing result.

Abstract: An equalization adaptation circuit comprises an equalizer, a transition determination circuit, a phase error circuit, a sequence recovery circuit, a phase error accumulator circuit, a transition accumulator circuit, and a controller circuit. The equalizer has adjustable parameters. The transition determination circuit determines observed transitions in an equalized signal output from the equalizer. A phase error circuit determines phase errors of the observed transitions. A sequence recovery circuit generates recovered digital data sequences. A phase error accumulator circuit accumulates the phase errors in respective association with pre-defined patterns matching the recovered digital data sequences containing observed transitions corresponding to the phase errors. A transition accumulator circuit accumulates a number of the observed transitions. A controller circuit controls the adjustable parameters of the equalizer based upon the accumulated phase errors and number of observed transitions.

Abstract: The present subject matter discloses a system and a method for estimating a frequency offset in communication devices. In one embodiment, the method of estimating a frequency offset in a communication device comprises generating a reconstructed signal based at least in part on a channel impulse response (CIR) corresponding to a received signal. Further, a normalization matrix is determined for the reconstructed signal. Thereafter, based at least in part on the normalization matrix and the reconstructed signal, the frequency offset is estimated such that the frequency offset corresponds to a maximum normalized-correlation between the reconstructed signal and the received signal.

Abstract: Circuitry for use in a receiver may comprise: a front-end circuit operable to receive an orthogonal frequency division multiplexing (OFDM) symbol on a first number of physical subcarriers. The circuitry may comprise a decoding circuit operable to decode the OFDM symbol using an inter-carrier interference (ICI) model, the decoding resulting in a determination of a sequence of symbols, comprising a second number of symbols, that most-likely correspond to the received OFDM symbol, where the second number is greater than the first number. The sequence of symbols may comprise N-QAM symbols, N being an integer. The ISCI model may be based, at least in part, on non-linearity experienced by the OFDM symbol during transmission by a transmitter, propagation over a channel, and/or reception by the receiver. The ISCI model may be based, at least in part, on phase-noise introduced to the OFDM symbol during transmission by a transmitter, propagation over a channel, and/or reception by the receiver.

Abstract: A method and an apparatus for transmitting and receiving data in a filter bank based multicarrier communication system are provided. The method includes receiving a plurality of data blocks and performing an Inverse Fast Fourier Transform (IFFT) operation on the plurality of data blocks, multiplying the plurality of data blocks on which IFFT has been performed and time axis filter coefficients, and transmitting a result obtained by adding the plurality of multiplied data blocks as a multi carrier signal.

Abstract: An embodiment of the invention is a technique to equalize received samples. A coefficient generator generates filter coefficients using an error vector and input samples. A filter stage generates equalized samples from input samples using the filter coefficients. The received samples are provided by a receiver front end in an optical transmission channel carrying transmitted symbols. Other embodiments are also described.

Abstract: A detection process for a receiver of a wireless communication system based on Multiple-In-Multiple-Out antennas, the process involving: —a preprocessing which only depends on the channel H, said preprocessing involving: —A QRD decomposition (61) for the purpose of decomposing said channel H into two Q and R matrices, with QHQ=I and R being upper triangular; —a lattice reduction (62) for the purpose of generating (formula AA, formula BB) and a permutation matrix T; —a loading phase (63, 64, 65) comprising a linear LRA-Minimum-Mean-Square-Error equalization applied on said symbols y in accordance with the result of said lattice reduction for the purpose of generating a value (formula CC).

Abstract: One or more embodiments describe a decision feedback equalizer with multiple cores for highly spectrally efficient communications. An equalization circuit in a receiver may include a decision feedback equalizer circuit having a first plurality of tap coefficients that are determined based on a cost function that receives as input an error signal that is an inter-symbol-correlated (ISC) signal. The decision feedback equalizer circuit may further include a second plurality of tap coefficients that are determined based on a filter with an ISC response. The cost function may determine the mean square of the error signal. The cost function is constrained or unconstrained. The error signal may represents error caused by a channel. In some embodiments, the ISC signal may be a partial response signal, and the filter with an ISC response may be a partial response filter.

Abstract: A system including a storage medium, a demodulator, and a decoder. The demodulator is configured to receive an input signal from the storage medium and demodulate the input signal. The decoder is configured to estimate data stored in the storage medium by decoding the demodulated input signal to provide an output signal. The decoder includes a filter and first and second processors. The filter is configured to generate a first equalized signal based on the output signal. The first processor is configured to, based on the first equalized signal and a first Viterbi algorithm, generate a first estimate of the data and an estimate of noise. The second processor is configured to generate a second estimate of the data based on the first estimate of the data, the estimate of the noise, and a second Viterbi algorithm. The output signal includes the second estimate of the data.

Abstract: A method comprises adapting a first tap weight of an equalizer, wherein a second tap weight of the equalizer is based at least in part on the first tap weight. Adapting the first tap weight further comprises computing a gradient from a data signal, an error signal and a channel pulse response sample. Adapting the first tap weight also comprises filtering the gradient with a loop filter and sending information to a transmitter via a back channel. Adapting the first tap weight further comprises configuring the first tap weight based on the information.

Abstract: A method of communication comprises partitioning a single-carrier data stream into equal-size blocks, and partitioning each block into a plurality of equal-size sub-blocks. A first set of cyclic prefixes and/or postfixes is inserted into the blocks to allow a linear convolution of a frequency-selective multipath channel having a long delay spread to be modeled as a circular convolution at a receiver. A second set of cyclic prefixes and/or postfixes is inserted into the sub-blocks to allow a linear convolution of a frequency-selective multipath channel having a short delay spread to be modeled as a circular convolution at the receiver. Upon receiving a transmitted data frame from the multipath channel, the receiver measures a link quality index (LQI) of a short channel impulse response; and selects block-by-block equalization or sub-block by sub-block equalization based on the LQI.

Abstract: Transmissions from mid-bus test equipment to a first device and from a second device to the mid-bus test equipment are equalized. Equalization instructions are passed from the first device through the mid-bus test equipment to the second device. The mid-bus test equipment changes the quality of transmissions sent to the first device in order to steer the first device to produce equalization instructions that will produce optimized transmissions from the mid-bus test equipment to the first device and from the second device to the mid-bus test equipment.

Abstract: 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.

Abstract: A tap coefficient control circuit and a method for controlling a tap coefficient for a decision feedback equalizer are disclosed. The method includes adjusting a correction voltage applied to the tap coefficient based on a first tap quantization and detecting a decision feedback equalizer tap convergence. After the decision feedback equalizer tap convergence is detected, the method adjusts the correction voltage applied to the tap coefficient based on a second tap quantization, wherein the second tap quantization is different from the first tap quantization.

Abstract: A method of estimating a level of severity of a network fault is provided. Performance parameters are monitored on upstream and downstream links to terminal network elements on a network to detect potential network faults. An alarm is raised with respect to a potential network fault automatically if at least one of the performance parameters as monitored crosses a preset threshold. After an alarm is raised, a level of severity is assigned to the alarm based on pre and post forward error correction (FEC) bit error rates (BER). In addition, the total number of terminal network elements that are impacted by the network fault is estimated and, when multiple alarms are raised of an equal level of severity, a higher priority is placed upon an alarm that affects service to a greatest number of terminal network elements.

Abstract: An equalizer is disclosed, and associated operational method. The equalizer has a configuration that balances performance and complexity by obtaining samples that are strongly correlated with future and past transmitted bits, and are weakly correlated with future and past bit transitions, and is useful for timing recovery circuits. Samples are only obtained or collected at time intervals more than one sample period away from the reference sample. Samples are shifted by a delay value less than the sample period, and are obtained at a sample period of one unit interval. A means to adjust the sampling point delay is also disclosed. In an implementation, samples that are within the sample period away from the reference sample are obtained and used for implementing a timing shift, not for equalization of the timing recovery signal. Embodiments are also disclosed for optimizing performance for data recovery.

Abstract: Apparatus includes a slave equalizer chain, which includes a first decoder and a first adaptive filter including first coefficients, and is configured to filter a first signal using the first adaptive filter to produce a first filtered signal, to decode the first filtered signal using the first decoder to generate a first output, and to adapt the first coefficients based at least on the first output. A master equalizer chain includes a second decoder and a second adaptive filter including second coefficients, and is configured to filter a second signal using the second adaptive filter to produce a second filtered signal, to calculate a weighted combination of the second filtered signal and the first filtered signal produced in the slave equalizer chain, to decode the weighted combination using the second decoder to generate a second output, and to adapt the second coefficients based at least on the second output.

Abstract: Methods, systems, and devices are described for compensating for transmit I/Q impairments in a digital signal. A frequency domain version of a first one of the components may be scaled at a wireless modem according to a frequency dependent I/Q impairment compensation function to obtain a compensated frequency domain version of the first one of the components. The compensated frequency domain version of the first one of the components may be combined with a frequency domain version of a second one of the components at the wireless modem to produce a compensated frequency domain version of the digital signal. The compensated frequency domain version of the digital signal may be transformed to the time domain at the wireless modem to produce a compensated time domain version of the digital signal.

Abstract: A method includes iteratively scanning, through a processor, at least a portion of a map of equalization coefficients related to channel equalization in a data communication link based on an ordinal integer step size S>1 for N (N>1) different sequences thereof to determine optimal points therein for which a signal quality in the data communication link is optimal. The method also includes performing, through the processor, a fine search for optimal equalization coefficients based on the determined optimal points.

Abstract: A method and wireless receiver for determining a modulation format of a transmitted signal from a received signal over a multipath channel are disclosed. The received signal has a frequency offset with respect to the transmitted signal. The wireless receiver down-samples the received signal. The down-sampled signal is equalized in order to mitigate an effect of multipath channel. Then the wireless receiver applies differential processing on the equalized signal to convert the frequency offset into a constant phase offset. Thereafter, values of one or more moment based features for the equalized signal are determined by the wireless receiver. The modulation format of the received signal is then determined based on the values of one or more moment based features.

Abstract: Provided is a receiver for processing VSB signal. The receiver includes a first equalizer/decoder unit and a second equalizer/decoder unit. The first equalizer/decoder unit performs a first equalizing operation, first TCM decoding and first RS decoding on a received symbol to output a first dibit. The second equalizer/decoder unit performs a second equalizing operation, second TCM decoding and second RS decoding on the received symbol to output a transport stream. The first dibit is provided as a priori information for a soft-decision operation of the second TCM decoding.

Abstract: Methods and apparatus are provided for determining one or more channel compensation parameters based on data eye monitoring. According to one aspect of the invention, a method is provided for evaluating the quality of a data eye associated with a signal. The received signal is sampled for a plurality of different phases, for example, using at least two latches, and the samples are evaluated to identify when the signal crosses a predefined amplitude value, such as a zero crossing. It is determined whether the points of predefined amplitude crossing satisfy one or more predefined criteria. One or more parameters of one or more channel compensation techniques can optionally be adjusted based on a result of the determining step. One or more parameters of an adjacent transmitter can also be adjusted to reduce near end cross talk based on a result of the determining step.

Abstract: A system and apparatus are disclosed for a method and apparatus for equalizing signals. An apparatus that incorporates teachings of the present disclosure may include, for example, an equalizer (100) having a channel estimation calculator (102) for calculating a time domain channel estimation from a baseband signal, an FFT processor (104) for translating the time domain channel estimation to a frequency domain channel estimation, a tap weight calculator (106) for calculating a frequency domain tap weight according to the frequency domain channel estimation, an inverse FFT processor (108) for translating the frequency domain tap weight calculation to a time domain tap weight calculation, and a filter (110) for equalizing the baseband signal according to the time domain tap weight calculation.

Abstract: One embodiment relates to an equalizer circuit for a data link. The equalizer circuit including a continuous-time linear equalizer, a first circuit loop, and a second circuit loop. The continuous-time linear equalizer receives a received signal and outputs an equalized signal. The first circuit loop determines a first average signal amplitude. The first average signal amplitude may be an average signal amplitude of the equalized signal. The second circuit loop a second average signal amplitude. The second average signal amplitude may be an average signal amplitude of a high-frequency portion of the equalized signal. Other embodiments and features are also disclosed.

Abstract: The transmitter and a mobile terminal based on interference alignment use pre-coding and pre-decoding methods. An antenna mapping matrix is computed according to a downlink channel state information, wherein the antenna mapping matrix is used for antenna mapping for the current transmitter to perform interference alignment. A multi-cell pre-coding matrix according to the downlink channel state information and the antenna mapping matrix; a single cell multi-user pre-coding matrix and pre-coding user data using the single cell multi-user pre-coding matrix and the multi-cell pre-decoding matrix and performing an antenna mapping using the antenna mapping matrix are computed. A system which cannot use the interference alignment method directly may be transformed to use the interference alignment method directly. In addition, the interference suppression between cells and the interference management inside cells are two separate processes, in which different linear pre-coding and decoding methods may be used.

Abstract: A receiver may be operable to receive a QAM-based, inter-symbol correlated (ISC) signal having pilot overhead of 5% at a signal-to-noise ratio (SNR). The receiver may be operable to process the QAM-based, ISC signal to output information at a particular rate with a symbol error rate lower than or equal to 1e-2. The first SNR may be at least 3 dB below a SNR required to achieve the same particular information rate and the same symbol error rate while processing a signal having zero inter-symbol interference.

Abstract: This equalization device and method, while preventing an expansion of circuit size, enable high-speed detection of a CIR in order to effectively achieve frequency domain equalization even when the phase of the received signal is significantly different from the phase of the known signal, and when the transmission channel has large temporal variations. A reference signal extraction unit (112) extracts both a real part component and an imaginary part component from the portion of the received signal including the known signal. A CIR detection filter unit (120) filters the known signal to generate a first processed signal and a second processed signal, detects real part filter coefficients by updating a first filter coefficient used in filtering the known signal in such a way that the first processed signal converges to the real part component, and detects imaginary part filter coefficients by filtering the known signal in such a way that the second processed signal converges to the imaginary part component.

Abstract: A method of wireless communication with improved performance employs an equalizer receiver with multiple receive antennas. Equalizer taps for linear filters of the equalizer receiver are generated by determining a conditioned covariance matrix of a first data path and a second data path based on a first gain (g0) of this first data path and a second gain (g1) of the second data path. The equalizer taps of the first data path and the second data path are determined based on the conditioned covariance matrix. The first data path and the second data path are then equalized using the equalizer taps. An equalized signal is generated by combining the equalized first data path with the equalized second data path.

Abstract: Disclosed is a deglitcher circuit having a programmable hysteresis. The deglitcher samples a received input signal, wherein the input signal may include one or more glitches. Responsive to a change in state of the sampled input signal, the deglitcher counts the number of samples of the changed state of the input signal. The count value increments with each sampled changed state, and decrements with each sampled original state of the input signal. When the count value reaches a threshold, the state of the output signal is changed. The output signal of the disclosed deglitcher circuit provides an accurate, glitch-free reconstruction of the sampled input signal. Additionally, the disclosed deglitcher circuit reduces the number of memory elements required for a given number of samples of the input signal, thereby allowing for a larger number of samples to be taken without necessarily having to increase the memory elements required by the deglitcher.

Abstract: 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.

Abstract: Methods and systems to configure a receiver based on a channel condition. A system may be implemented to estimate a channel based on PN sequences in a received signal, concurrently equalize a frequency domain representation of the signal with multiple blind adaptive equalizers, and evaluate results of the equalizations to select coefficients of one of the equalizers for further processing. A first equalizer may implement a constant-step-size (CSS) algorithm for a static channel. A second equalizer may implement a variable-step-size (VSS) algorithm for a dynamic channel. Static and dynamic channels may be distinguished based on convergence/divergence of the equalizers, which may be determined from a mean square error estimated from PN sequences in results of the blind equalizations.

Abstract: Methods of efficient calculation of initial equaliser coefficients are described. In a first stage, a channel matched filter is generated based on an estimate of CIR and then used to filter the CIR estimate. In a second stage, initial FFE coefficients are calculated from a portion of the match filtered CIR and then these initial FFE coefficients and the estimate of CIR may be used to generate initial DFE coefficients. In various embodiments, a window is applied to the CIR estimate before the matched filter is generated. In various embodiments, the second stage is iterated to minimise the pre-echoes following the FFE.

Abstract: A two-channel time-interleaved analog-to-digital converter (TIADC) system that provides for estimation and correction of offset, gain, and sample-time errors. Error in the offsets of the two ADCs that form the TIADC produces a spurious signal at the Nyquist frequency that can be used to minimize the difference of offsets of the ADCs. The difference in gain between the two ADCs produces spurious signals reflected around the Nyquist frequency whose magnitudes can be reduced by minimizing the difference in signal power between the two ADCs. An Automatic Gain Control loop corrects the scaling of the input signal due to the average of the gains of the ADCs. Phase error produces spurious signals reflected around the Nyquist frequency that are ?/2 out of phase with those due to the gain error. Minimizing the difference between the correlation of consecutive signals from the ADCs reduces the magnitude of these image tones.