Abstract: One embodiment relates to a receiver circuit for multi-level amplitude signaling which includes at least three amplitude levels for each symbol period. The receiver circuit includes a peak detector, a reference voltage generator, and a comparator circuit. The peak detector is arranged to detect a peak voltage of the multi-level amplitude signal, and the reference voltage generator uses the peak voltage to generate multiple reference voltages. The comparator circuit uses the multiple reference voltages to detect an amplitude level of the multi-level amplitude signal. Other embodiments and features are also disclosed.

Abstract: A method, apparatus and computer program product are configured to provide calibration accuracy in an analog filter. In this regard, a method is provided that includes estimating a cutoff frequency for an analog filter. The method further includes causing a filter tuning word to be modified based on the estimated cutoff frequency for the analog filter. The method also includes determining a residual cutoff frequency mismatch for the analog filter. The method also includes causing an equalizer configuration to be selected for a digital filter based on the determined residual cutoff frequency mismatch.

Abstract: A nonlinear echo compensator comprises a mapping circuit that includes a weighting circuit that generates a weighted signal based on a current symbol and a prior symbol and a function generating circuit that selects one of N functions based on the weighted signal, where N is an integer greater than one. The mapping circuit generates a driving signal based on the selected one of the N functions and the weighted signal. A canceling circuit generates a nonlinear echo compensation signal based on the driving signal.

Abstract: A receiver includes an antenna interface, a frequency translation bandpass filter (FTBPF), a sample and hold module, and a down conversion module. The antenna interface is operable to receive a received wireless signal from an antenna structure and to isolate the received wireless signal from another wireless signal. The FTBPF is operable to filter the received wireless signal to produce an inbound wireless signal. The sample and hold module is operable to sample and hold the inbound wireless signal in accordance with an S&H clock signal to produce a frequency domain sample pulse train. The down conversion module is operable to convert the frequency domain sample pulse train into an inbound baseband signal.

Abstract: A receiver having Inphase-Quadrature (I-Q) imbalance compensation and an I-Q imbalance compensation method are provided. The receiver calculates a cross-ratio parameter according to a first ideal receiving value and a first ideal conjugate receiving mirror of a first receiving signal and a second ideal receiving value and a second ideal conjugate receiving mirror of a second receiving signal. The receiver calculates an I-Q imbalance compensation parameter according to the cross-ratio parameter, the first ideal receiving value, the first ideal conjugate receiving mirror, the second ideal receiving value, the second ideal conjugate receiving mirror, the first receiving signal and the second receiving signal. The receiver compensates a third receiving signal according to the I-Q imbalance compensation parameter.

Abstract: A local carrier wave output from a synthesizer to quadrature demodulators is multiplied by an offset that makes a frequency shift by an integer number of subcarriers in units of sub-carrier bands. The offset is set to a value obtained by multiplying the number sequentially counted up from 0 to the number of unused sub-carriers included in guard tones in a signal band by the bandwidth of a sub-carrier. By shifting the frequency of the local carrier wave at the time of quadrature demodulation with the offset, the SNR of a baseband signal is prevented from being constantly degraded by a frequency characteristic possessed by the circuit of a receiver in a particular sub-carrier signal. Especially, by preventing a pilot signal from being constantly degraded, the signal can be received with higher accuracy.

Abstract: Provided is a method of generating an adaptive codebook and a multiple input multiple output (MIMO) communication system using the adaptive codebook. A transmitter and a receiver may generate, from a base codebook based on a matrix associated with statistics of a channel matrix, the adaptive codebook maintaining a unitary characteristic. The transmitter may perform scheduling, transmit filter design, and precoding using adaptive codebook based feedback information.

Abstract: The quality of a received signal in a non-linear receiver is estimated using a coupling matrix G or Q that describes the interaction of symbols in the received signal with other symbols and/or how the impairment (noise and interference) interacts in the received signal. The coupling matrix is also useful for joint detection. The signal quality estimate may include, e.g., the minimum eigenvalue, and other functions, such as the determinant and trace of the coupling matrix. When G or Q varies with each block, as in CDMA systems employing longcode scrambling, a representative matrix can be used, such as a matrix of RMS values or average magnitudes of real and imaginary components. The signal quality estimate can be expressed as a bit error rate (BER).

Abstract: Provided are a method and apparatus (receiver) of receiving and processing a radio signal in a transmitter-receiver environment. The radio signals are transmitted across a wireless interface using Ultra Wideband (UWB) pulses. A transmitted reference approach is utilized. The radio signal include pairs of UWB pulses with each pair of pulses separated by a fixed time delay. The two pulses are then combined to provide for improved noise immunity.

Abstract: The present invention discloses a method and apparatus for wide dynamic range phase conversion. In one embodiment, inphase and quadrature signal components of a complex input signal are collapsed into a single quadrant to produce a first signal representation. A scaling operation is subsequently performed on the first signal representation to produce a second signal representation. Lastly, the second signal representation is converted into the phase domain.

Abstract: A method of processing a boot sequence for a processor forming a part of a module apparatus involves interrogating a host television device to determine if the host television device requires use of an application execution engine residing on the module apparatus; receiving a reply to the interrogation; and responsive to the reply, establishing a mode of operation wherein the application execution engine is used to execute application code for the host television device. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.

Abstract: A receiver/transmitter and related receiving/method capable of simultaneously receiving/transmitting discontinuous frequency band signal components of an input/output signal are provided. Phase swapping on in-phase/quadrature-phase local oscillation differential signals is applied to frequency down-conversion of the input signal or frequency up-conversion of a baseband signal to be outputted to radio domain, and thereby achieve simultaneously receiving discontinuous frequency bands of the input signal and simultaneously sending different baseband signal components on discontinuous frequency bands of the output signal.

Abstract: In a synchronization processing circuit in a wireless communication system, a correlation operation unit is designed to have a parallel structure which can be restructured to improve flexibility in order to cope with various synchronization processings in a plurality of radio systems. The synchronization processing circuit in the wireless communication system comprises a plurality of correlation operation modules 31 through 3N that execute correlation operation, each of which correlation operation modules includes a plurality of correlators 60, a plurality of shift registers 50 for shifting a correlation code, an interface which transfers a shifted correlation code to an adjacent correlation operation unit for timing correlation processing, and a correlation code selection unit 40 which selects an externally and individually applied correlation code for code correlation processing and a correlation code transferred from an adjacent correlation operation unit as the correlation code.

Abstract: Improving the reliability of digital radio communication affected by multi-path interference under an environment where there are multiple objects that scatter electromagnetic waves is accomplished. A wireless transmitter transmits a first transmission wave having a first carrier frequency (f0+?f), modulated by a modulator with an information signal having a frequency band f1 which is predetermined, from a transmitting antenna, and transmits a second transmission wave having a second carrier frequency (f0??f), modulated by a modulator with such information signal. An average frequency f0 between the first carrier frequency (f0+?f) and the second carrier frequency (f0??f) is kept constant, whereas the first carrier frequency (f0+?f) and the second carrier frequency (f0??f) are varied by controlling a frequency difference ?f to vary.

Abstract: A high temperature communications circuit includes a power conductor for concurrently conducting electrical energy for powering circuit components and transmitting a modulated data signal, and a demodulator for demodulating the data signal and generating a serial bit stream based on the data signal. The demodulator includes an absolute value amplifier for conditionally inverting or conditionally passing a signal applied to the absolute value amplifier. The absolute value amplifier utilizes no diodes to control the conditional inversion or passing of the signal applied to the absolute value amplifier.

Abstract: In various aspects, the disclosure describes systems and methods for decoding of convolutionally encoded signals representing, for example, telecommunications signals such as command or content signals used in digital telecommunications. In various embodiments such aspects of the disclosure provide systems and methods for improving the efficiency, speed, and power consumption of such processes by providing architectures and methods for processing various parts of the encoded data records in parallel, using multiple and optionally specially-designed, dedicated memory registers and multiplexers.

Abstract: A pipelined decision feedback unit (DFU) is disclosed for use in reduced-state Viterbi detectors with local feedback. The disclosed pipelined decision feedback unit improves the maximum data rate that may be achieved by the reduced state Viterbi detector by the pipelined computation of partial intersymbol interference-based estimates. A pipelined decision feedback unit is thus disclosed that computes a plurality of partial intersymbol interference based estimates, wherein at least one partial intersymbol interference-based estimate is based on a selected partial intersymbol interference-based estimate; and selects the selected partial intersymbol interference-based estimate from among partial intersymbol interference-based estimates for path extensions into a state.

Abstract: A technology for modulating and demodulating a burst signal in a return link of a satellite system, in which the burst signal is modulated and transmitted from a transmission end of the return link and a symbol of the burst signal is identified and demodulated at a receiving end. The method includes estimating symbol timing of a burst received through the return link and synchronizing the estimated symbol timing of the burst to reference symbol timing; synchronizing a location of the timing-synchronized burst having the symbol timing synchronized to a location of a reference burst using a preamble symbol and a post-amble symbol of the timing-synchronized burst; and recovering a carrier of the location-synchronized burst whose location has been synchronized to the location of the reference burst using a pilot symbol of the location-synchronized burst.

Abstract: Systems and techniques relating to wireless communications are described. A described technique includes generating a digital transmit signal; receiving a digital receive signal that is based on an amplified analog version of the digital transmit signal, where the amplified analog version is produced by a power amplifier having a nonlinear characteristic(s); storing signal samples; determining gain coefficients based on the signal samples, the gain coefficients being associated with respective first operational ranges of the power amplifier; determining predistortion values, and using the predistortion values to predistort digital signals to compensate for the nonlinear characteristic(s) of the power amplifier.

Abstract: An integrated circuit comprises channel estimation module for generating at least one channel estimation signal based on at least one of a plurality of pilot signals within concurrent resource elements. The channel estimation module comprising extension module arranged to receive a demodulation reference signal comprises the plurality of pilot signals and to add an extension to the demodulation reference signal, inverse discrete Fourier transform (IDFT) module arranged to perform an inverse discrete Fourier transform function on the extended demodulation reference signal to generate a time domain reference signal, reference signal separation module arranged to separate out at least one pilot signal component from the time domain reference signal. The channel estimation module further comprises and discrete Fourier transform (DFT) module arranged to perform a discrete Fourier transform function on the at least one pilot signal component to generate at least one extended channel estimation signal.

Abstract: A signal demodulation method is disclosed, which includes: obtaining a complete transmission code word; calculating estimated values of three non-differential phases of the transmission code based on a majority logic; identifying a most unreliable phase among three non-differential phases and determining the other two reliable phases to obtain their determination values; calculating determination values of the rest two phases based on the two determined phases; and looking up in tables based on determination values of the four phases to obtain incoming bits. The demodulation method of the present invention is capable of sufficiently reducing the effect of noise on signal and effectively improving the signal demodulation performance.

Abstract: A process receives a composite signal transmitted via a nonlinear data transmission channel, with the composite signal having a first signal UL and a second signal LL. The process includes the following: demodulating and decoding the first signal UL by using a first demodulation and decoding chain in order to regenerate first information of the first signal UL; recoding and shaping to produce a continuous time waveform; applying a nonlinearity function based on a set of coefficients updated according to an adaptive correlation calculation process to the continuous time waveform; subtracting the result of the nonlinearity function from the composite signal in order to generate a result E; and demodulating and decoding the result E by using a second demodulation and decoding chain in order to regenerate second information of the second signal LL.

Abstract: In various embodiments, a first and second complex multiplier may be configured to receive an input signal and provide a baseband I component signal and a baseband Q component signal, respectively. A first and second filter may be configured to filter the baseband I component signal and the baseband Q component signal, respectively. An equalizer may be configured to equalize the filtered baseband I component signal and the filtered baseband Q component signal. A carrier recovery portion may be configured to generate a reference signal based on the equalized filtered baseband I component signal and the equalized filtered baseband Q component signal. A first and second multilevel comparator may be configured to receive the equalized filtered baseband I component signal from the carrier recovery portion and provide an output I and receive the equalized filtered baseband Q component signal and provide an output Q signal for further modulation.

Abstract: Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.

Abstract: Systems and methods which provide for reduced intra communication system information transfer by providing a compressed representation of a portion of intra communication system information are shown. An embodiment operates to provide intra communication system transfer of uncompressed received information while providing intra communication system transfer of a compressed representation of information ancillary to the received information. According to embodiments, ancillary information, such as CSI, associated with other transferred information is transferred with reduced data throughput requirements through application of compression techniques with respect to the transferred ancillary information. Embodiments additionally or alternatively reduce the intra communication system information transferred by reducing the received information transferred.

Abstract: Wireless communication is ubiquitous today and deployments are growing rapidly leading to increased interference, increasing conflicts, etc. As a result monitoring the wireless environment is increasingly important for regulators, service providers, Government agencies, enterprises etc. Such monitoring should be flexible in terms of the networks being monitored within the wireless environment but should also provide real-time monitoring to detect unauthorized transmitters, provide dynamic network management, etc. Accordingly, based upon embodiments of the invention, a broadband, real-time signal analyzer (RTSA) circuit that allows for the deployment of RTSA devices in a distributed environment wherein determination of policy breaches, network performance, regulatory compliance, etc. are locally determined and exploited directly in network management or communicated to the central server and network administrators for subsequent action.

Abstract: A receiver has a bandwidth. The receiver includes paths, a first receiver module, an enable module, and a second receiver module. The paths are configured to be enabled to receive signals. The first receiver module is configured to, prior to the receiver receiving the signals, detect a number of the paths that are enabled to receive a signal. The enable module is configured to, based on the number of the paths detected to have been enabled (i) determine if the signals to be received by the receiver are receivable by a number of the paths less than the number of the paths detected to have been enabled, and (ii) disable, based on a result of the determination, one or more of the paths detected to have been enabled. The second receiver module is configured to, based on the number of the paths enabled, adjust the bandwidth of the receiver.

Abstract: A wireless device includes processing circuitry, a receiver section, a transmitter section, and an antenna. The processing circuitry determines a set of information signals of a RF Multiple Frequency Bands Multiple Standards (MFBMS) signal. The receiver section down-converts a portion of the RF MFBMS signal by one or more respective shift frequencies to produce a corresponding baseband/low Intermediate Frequency (BB/IF) information signal from which the processing circuitry extracts data. The transmitter section converts a respective BB/IF information signal received from the processing circuitry by a respective shift frequency to produce a corresponding RF information signal and a combiner that combines the RF information signals to form a RF MFBMS signal. The receiver section and the transmitter section include ADCs and/or DACs, respectively, that are adjustable based upon characteristics of the RF MFBMS signal, the BB/IF MFBMS signal, and/or based upon signals carried therein, e.g.

Abstract: An I/Q demodulation apparatus and method with phase scanning are provided. The demodulation apparatus includes a ring oscillator, a first latch unit, a decoding unit, a counter unit, a second latch unit, a first arithmetical unit and a second arithmetical unit. The first latch unit samples phase signals outputted from the ring oscillator. The decoding unit decodes the output of the first latch unit to correspondingly generate fine code of a first, a second, a third and a fourth codes. The counter unit counts the phase signals. The second latch unit samples the output of the counter unit to correspondingly generate coarse code of the first, the second, the third and the fourth codes. The first arithmetical unit performs an addition/subtraction operation by using the first code and the second code. The second arithmetical unit performs the addition/subtraction operation by using the third code and the fourth code.

Abstract: The invention relates to a detection method using a receiver of a digital communication system for the detection of a symbol from a received signal, which signal is transmitted by a transmitter of the digital communication system, wherein the symbol is a selected symbol out of a predetermined set of symbols and wherein each symbol of the predetermined set comprises a sequence of chips wherein each of the chips is PSK-modulated according to a selected modulation code.

Abstract: A configurable decoder within a receiver (for example, within a wireless communication device) includes numerous decoders. In one mode, the multiple decoders are used to decode different sub-packets of a packet. When one decoder completes decoding the last sub-packet assigned to it of the packet, then that decoder generates a packet done indication. A control circuit receives the packet done indications, and when all the decoders have generated packet done indications then the control circuit initiates an action. In one example, the action is the interrupting of a processor. The processor responds by reading status information from the control circuit, thereby resetting the interrupt. End-of-packet markers are usable to generate packet done indications and to generate EOP interrupts. Similarly, end-of-group markers are usable to generate group done indications and to generate EOG interrupts. The decoder block is configurable to process sub-packets of a packet using either one or multiple decoders.

Abstract: A quadrature bandpass-sampling receiver for an orthogonal frequency division multiplexing (OFDM) receiver is provided. A transmitted OFDM signal is received by a low-noise amplifier, has its image frequency removed by a subsequent image reject filter, and is frequency-translated to an intermediate frequency by a mixer. A quadrature bandpass-sampling delta-sigma analog-to-digital demodulator (QBS-ADD) down-converts the frequency-translated OFDM signal to baseband based on a high-frequency sampling clock equal to the intermediate frequency, and generates in-phase and quadrature outputs in the form of high-frequency bit streams. The bit streams are fed to a Discrete Fourier Transform (DFT) engine, which generates in-phase and quadrature Fourier components.

Abstract: Certain aspects of the present disclosure propose methods and apparatus for low complexity soft-in soft-out detection that divide a plurality of received symbols into a plurality of groups of symbols and performs preprocessing on the symbols in each group to suppress interference from other groups. The preprocessing may utilize a priori information for one or more symbols in one or more groups that are not yet detected, and/or a posteriori information for one or more symbols in one or more groups that are already detected and/or decoded. The preprocessed symbols may then be detected using a soft-in soft-out detection algorithm.

Abstract: A calibration technique to compensate for the quadrature phase error between the in-phase and quadrature sampling clocks controlling the quadrature bandpass sampling delta-sigma analog-to-digital demodulator (QBS-ADD) is provided. A low-frequency test tone is injected in the feedback path, up-converted to the radio frequency (RF) frequency, and added to the input of the QBS-ADD. The test tone is demodulated by the QBS-ADD into an in-phase signal and a quadrature signal. The in-phase and quadrature signals are converted into the frequency domain by the discrete Fourier transform. The quadrature phase error is quantified based on the complex Fourier complex coefficients; and the phase difference between the in-phase and quadrature sampling clocks is corrected.

Abstract: A method and circuit for performing channel equalization in a high speed transmission system comprising a transmitter and receiver. An application specific digital signal processor, ASDSP, performs channel equalization and compensation on digital data received from an analogue-to digital converter of the receiver. The ASDSP is operable to execute an application specific set of op-codes needed for performing channel equalization and compensation. An ASDSP register is coupled between the ASDSP and a system CPU in a feedback loop for performing channel equalization at the receiver. The ASDSP stores equalizer parameters and bit error rate measurements used by the ASDSP for performing channel equalization and compensation. An ASDSP program storage memory, coupled to and accessible by the ASDSP, stores an ASDSP micro-sequence program for controlling the processing steps for channel equalization and dataflow through the ASDSP.

Abstract: A receiving circuit, a transmitting circuit, a micro-controller, and a method for power line carrier communication. The receiving circuit includes: an analog amplifier, a receiving filter, an analog-to-digital converter, a digital mixer, a digital filter, and a digital demodulator connected successively. The transmitting circuit includes: a digital modulator, a gain controller, a digital-to-analog converter, a transmitting filter, and a transmitting amplifier connected successively. The micro-controller includes a central processor and the receiving circuit or the transmitting circuit. The method for power line carrier communication can be implemented based on the receiving circuit or the micro-controller.

Abstract: A quadrature demodulator receiver unit (100) comprises a first filter unit (360) that may delay an intermediate signal x(t) whose real part is based on a sampled in-phase IF signal (xi(t)) and whose imaginary part is based on a sampled quadrature IF signal (xq(t)). A second filter unit (366) filters a conjugate complex version of the intermediate signal x(t). The filter coefficients of the filter units (360, 366) are determined using a calibration signal, for example on the basis of ratios of complex-valued spectral components of intermediate signals xcal(t) obtained from the calibration signal cal(t). The filtered signal and the delayed signal are recombined to obtain a compensated output signal y(t). The calibration signal may be supplied from an oscillator circuit supplying a signal for processing a receive signal of the receiver unit (100).

Abstract: A plurality of sub-channel response estimates corresponding to a plurality of contiguous sub-channels in a communication channel are determined, and a plurality of weight coefficients are determined. The plurality of sub-channel response estimates are multiplied with the plurality of weight coefficients to generate a plurality of weighted sub-channel response estimates. A filtered sub-channel response estimate for one of the plurality of contiguous sub channels is generated using the plurality of weighted sub-channel response estimates.

Abstract: A device for detecting a cyclic prefix length according to the present invention includes: a plurality of cyclic prefix length searchers that receive a received signal from a transmitting apparatus to search different cyclic prefix lengths for the received signal; a normalizer that receives and normalizes a plurality of search results received from each of the plurality of cyclic prefix length searchers and outputs a plurality of normalization values; and a determining unit that determines any of the normalization values as the cyclic prefix length of the received signal.

Abstract: A method for remotely detecting electromagnetic interference on a data transmission line of a communication network includes measuring at a client site a noise power spectrum on the data transmission line as a function of frequency, for a frequency range. The noise is present when the data transmission line is not carrying a data signal. The method further includes forwarding the measured noise power spectrum to a remote computer at a network operator's site, determining periodicities in the measured power spectrum by the remote computer, and determining the switching frequency of a power supply unit at the client site by the remote computer based on periodicities in the power spectrum.

Abstract: A system (55-1) for correcting gain imbalance and phase imbalance between first (IOUT) and second (QOUT) signals which are 90° out of phase, including circuitry (32) for estimating the phase mismatch (?) and gain mismatch (?) between the first signal and the second signal signals in a plurality of frequency bands. An inverse fast Fourier transform is performed on each of a number of arrays of the phase mismatch estimates and the gain mismatch estimates to generate correction filter coefficients (h[N]) for a N tap correction filter (61). The N tap correction filter filters an uncorrected value of the second signal to generate a corrected value of the second signal.

Abstract: The data processing unit (15) for a receiver of signals carrying information (1) includes a clock and data recovery circuit (16) on the basis of a data signal (DOUT), and a processor circuit (17) connected to the clock and data recovery circuit. The clock and data recovery circuit is clocked by a local clock signal (CLK) and includes a numerical phase lock loop, in which a numerically controlled oscillator (25) is arranged. This numerically controlled oscillator generates an in-phase pulse signal (IP) and a quadrature pulse signal (QP) at output. The frequency and phase of the pulse signals IP and QP are adapted on the basis of the received data signal (DOUT). The processor circuit is arranged to calculate over time the mean and variance of the numerical input signal (NCOIN) of the numerically controlled oscillator (25), so as to determine the coherence of the data signal if the calculated mean and variance are below a predefined coherence threshold.

Abstract: A receiver circuit includes an asynchronous demodulator having a demodulator input to receive a first signal and a demodulator output configured to provide a demodulated signal. The receiver circuit further includes a circuit, a multiplexer, and a synchronous demodulator. The modulator circuit includes a modulator input coupled to the demodulator output and includes a modulator output. The modulator re-modulates the demodulated signal to produce a second signal and provides the second signal to the modulator output. The multiplexer includes a first input to receive the first signal, a second input coupled to the modulator output to receive the second signal, a control input to a receive a select signal, and a multiplexer output. The synchronous demodulator includes an input coupled to the multiplexer output and an output to provide a demodulated output signal corresponding to a selected one of the first signal and the second signal.

Abstract: A receiver of a multiple-input multiple-output (MIMO) system performs QR decomposition of the channel matrix to enable detection of a transmitted vector in a layered manner. In each layer, a sub-vector of the transmitted vector is estimated. A reactive tabu search is performed if an estimated symbol differs from a nearest symbol in the alphabet by a predetermined value. The receiver may order the entries of the channel matrix prior to QR decomposition to enable estimation in an optimum order. In another embodiment, a receiver performs multiple reactive tabu searches to estimate a transmitted vector. The receiver employs a fixed threshold or a variable threshold for a cost function used in the multiple reactive tabu searches depending on whether the MIMO system is under-determined or not. The techniques enable low bit-error rate (BER) performance in MIMO systems with large number of antennas and when higher-order modulation techniques are used.

Abstract: A method and an apparatus for achieving fast resynchronization of received signals in a time slice in DVB-T/H systems. When the clock drift is low, the location of the symbol window can be decided based on a previous time slice. When the clock drift is high and when there are large delay spreads, the location of the symbol window can be decided based on the detected scattered pilot positions. The placement of the symbol window can further be enhanced through processing of the received TPS bits.

Abstract: An LTE baseband receiver and a method for operating the receiver are provided. The receiver comprises a frequency selective interference estimator, an interference level averager and an interference assessor operative to control which output of the frequency selective interference estimator or the interference level averager is to be supplied to a soft-metric calculator. Frequency selectivity of the interference is assessed, and the best mode of interference estimation is selected to increase LTE receiver performance in loaded networks without impacting receiver performance in unloaded networks.

Abstract: A method for estimating transceiver non-idealities is disclosed. In one aspect, the method comprises generating a preamble comprising multiple sets of known training sequences with a synchronization part preceding an estimation part. The training sequences in the estimation part comprises at least two sequences which are (i) complementary Golay sequence pairs and (ii) selected to satisfy a predetermined correlation relationship chosen for estimation of a first non-ideality characteristic. A first estimate of a non-ideality characteristic is determined on the basis of the known training sequences of the synchronization part of the received preamble. The estimation part of the received preamble is compensated by this estimate. Another non-ideality characteristic is determined by the compensated estimation part, exploiting the predetermined correlation relationship.

Abstract: Systems and methods are provided for channel estimation using linear phase estimation. These systems and methods enable improved channel estimation by estimating a linear channel phase between received pilot subcarrier signals. The estimated linear phase can then be removed from the received pilot subcarrier signals. After the estimated linear phase is removed from the received pilot subcarrier signals, a channel response can be estimated. A final estimated channel response can be generated by multiplying the results of the linear channel estimation by the estimated linear phase.

Abstract: A method for demodulating a modulated signal, by: receiving a signal modulated in n-PSK or n-APSK comprising a succession of symbols organized in frames, each frame comprising a header followed by blocks of data symbols separated by blocks of pilot symbols, determining the phase of the headers and pilot blocks to predict the evolution of the signal phase, correcting the phase of the data symbols according to the evolution of the signal phase, and equalizing the data symbols corrected in phase using equalization coefficients evaluated thanks to estimated or known symbols of the signal, and pre-equalizing the header, pilot and data symbols, which is performed before determining the phase of the headers and pilot blocks, and using the estimated equalization coefficients to equalize the data symbols.

Abstract: Teachings presented herein offer a technique for using a demodulator to improve a demodulation process. For example, a demodulation unit according to an embodiment of the present invention may be a multi-stage demodulator and may include: a demodulator configured to receive a baseband signal and configured to produce modem bit likelihood values based on the received baseband signal; a decoder configured to receive and process the modem bit likelihood values to produce improved modem bit likelihood values; a candidate value generator configured to produce, based on the improved modem bit likelihood values, candidate symbol values for a group of one or more symbols; and a detector configured to receive the baseband signal and the candidate symbol values and configured to produce one of (a) final modem bit estimates and (b) candidate symbol values for a group of symbols.