Abstract: A system for decoding frequency modulated signals includes a glue logic module, a key matrix, and a driver coupled to the key matrix. The glue logic module provides a pre-scaled frequency signal, while the key matrix receives the pre-scaled frequency signal. The driver decodes the pre-scaled frequency signal to generate at least one event update corresponding to a frequency of the pre-scaled frequency signal.

Abstract: A receiving device includes a FFT unit performing FFT on an input signal of a time domain to transform the input signal into a plurality of signals of frequency domains and outputting the plurality of signals of the frequency domains, a signal extracting unit extracting a signal with a power that is greater than a threshold value from among the plurality of signals of the frequency domains output from the first FFT unit and outputting the extracted signal, an IFFT unit performing IFFT on the extracted signal output from the signal extracting unit, a subtracting unit subtracting the extracted signal output from the IFFT unit from the input signal and outputs a subtracted signal, and a second FFT unit transforming the subtracted signal output from the subtracting unit into a signal of the frequency domain by performing the FFT on the subtracted signal output from the subtracting unit.

Abstract: A fractional rate converting filter in a wireless transceiver comprising a delay line, multiplier circuit, adder circuit, and selector. The delay line receives a digital input signal at a first sample rate and has delay blocks each providing an output and receiving samples gated at a plurality of clock cycles of an integer sub-multiple frequency of a clock. The outputs are multiplied by corresponding filter tap coefficients. Each filter tap coefficient is spaced by a first integer Y. The adder circuit receives and sums the tap outputs to provide an output signal. The selector iteratively shifts the coefficients by a second integer Z. The output of each delay block is multiplied by corresponding shifted filter tap coefficients. The delay blocks are inhibited from receiving another input sample during the plurality of clock cycles. The output signal has a second sample rate at the integer sub-multiple frequency of the clock.

Abstract: This disclosure concerns beam-forming vectors and beam-forming matrices for multiple-input, multiple-output (MIMO) communications systems. These systems, from the method perspective, provide, according to one embodiment, a method of feeding back, to a transmitter from a receiver in a MIMO communications system, at least part of a beam-forming vector of a beam-forming matrix, wherein: the vector relates to a spatial stream of the MIMO system; the vector comprises a series of elements; each element specifies a beam-forming weight for a respective transmit antenna of the transmitter; and the method comprises: calculating a scaling factor that would scale a first element of the vector to a value of one; scaling the other element or elements of the vector with the scaling factor; and feeding back the scaled other element or elements to the transmitter to inform a beam-forming process.

Abstract: The teachings herein provide a method and apparatus for partitioning sets of MIMO streams, for joint processing. In particular, there is an optimum or otherwise best partitioning of a set of MIMO streams into a first subset to be jointly processed and a second subset to be suppressed as interference with respect to that joint processing. Of course, more than one partitioning may be used, e.g., across different joint processing stages and/or at different times, such that all streams of interest are processed. Correspondingly, the present invention provides a method and apparatus for selecting an optimum or otherwise relative “best” subset of MIMO streams for processing together in a joint process, from among a larger set of MIMO streams. The method and apparatus may, for example, be employed in a multi-stage joint processing receiver, where subset selections are performed on a per-stage basis.

Abstract: Disclosed herein are methods of processing transmissions in a wireless communication system to detect whether a transmission unit contains transmitted data, systems for processing transmissions in a digital communications system to detect the same, receivers for processing transmissions in a wireless communications system and computer readable media implementing a method for processing the same. In one embodiment, a method of processing transmissions in a wireless communication system to detect whether a transmission unit contains transmitted data includes: generating an averaged function of bit reliability indicators from a plurality of received samples and applying a test to compare an average of ln cosh(·) (natural logarithm of the hyperbolic cosine) values for the reliability indicators, with a factor proportional to an average signal-to-disturbance ratio of the plurality of samples to determine if the transmission unit contains transmitted data.

Abstract: An apparatus for canceling interference includes a plurality of converters, a plurality of interference cancellation units, a plurality of variance detectors, and an output selecting unit. The plurality of converters converts a plurality of received signals to a plurality of frequency domain signals, respectively. The plurality of interference cancellation units cancel interference in the plurality of frequency domain signals using a plurality of interference cancellation schemes to generate a plurality of interference-canceled signals corresponding to the plurality of interference cancellation schemes, respectively. The plurality of variance detectors measure a plurality of amounts of residual interference corresponding to the plurality of interference-canceled signals, respectively.

Abstract: Apparatus and methods are provided for computing soft information at a receiver having a plurality of receive antennas. The receiver may be a mobile station or a base station, and can receive a signal vector that includes an intended signal from a first source as well as interfering signals from one or more other, interfering sources. The receiver can determine modulation information, such as the modulation scheme, used by each of the interfering sources. The mobile station can also estimate channel information, such as channel gain information, associated with each interfering source. Using the modulation and channel information, the receiver can compute soft information, such as a log-likelihood ratio. In some embodiments, the receiver can adaptively determine which interference sources and which receive antennas to use when computing the soft information.

Abstract: A control signal receiver includes a converting circuit and a synchronization detection circuit. The converting circuit generates a complex control symbol stream including transmission configurations by converting an input signal. The synchronization detection circuit generates a first bit stream by applying a first determination criterion to the complex control symbol stream and generates a first synchronization signal by comparing the first bit stream with a reference synchronization word. The synchronization detection circuit generates a second bit stream by applying the first determination criterion and a second determination criterion to the complex control symbol stream in that order and generates a second synchronization signal by comparing the second bit stream with the reference synchronization word. The synchronization detection circuit outputs one of the first synchronization signal and the second synchronization signal as asynchronization enable signal.

Abstract: A communication apparatus and a channel estimating method for performing channel estimations with high precision. The communication apparatus, which receives multicarrier signals comprising a plurality of subcarriers, has a first estimating unit that generates temporary channel estimation values from pilot signals located in any ones of a plurality of received subcarriers; a second estimating unit that generates a virtual channel estimation value sequence related to the frequency bands other than the frequency bands of the plurality of subcarriers and that combines the generated virtual channel estimation value sequence with the plurality of temporary channel estimation values to generate a channel estimation value sequence corresponding to a predetermined frequency bandwidth; and a generating unit that uses this generated channel estimation value sequence to generate channel estimation values related to any ones of the plurality of subcarriers.

Abstract: According to one embodiment, a receiving apparatus includes a variable gain amplifier, comparator, and signal processor. The comparator compares a signal level of the second signal with a first threshold to generate a third signal, a signal level of the third signal being set to a high signal if the signal level of the second signal is greater than the first threshold. The signal processor determines presence of a signal if a rate of high signals in third signals for a period is greater than a second threshold. The second threshold is set to a first value when the control of the gain is performed and set to a second value when the demodulation processing is performed. The first value is greater than the second value.

Abstract: A method of reducing signal correlation in a symmetrical adaptive canceller link comprising spectrally inverting one of a first carrier signal and a second carrier signal by causing a spectral inversion of one of the first and second carrier signals using a modulator, transmitting the first and second carrier signals within a bandwidth to a remote receiver using a transmitting device such that a composite carrier signal results, and cancelling at least one of the first carrier signal from the composite carrier signal using a cancellation technique such that the second carrier signal results on one end of the link and the second carrier signal from the composite carrier signal using a cancellation technique such that the first carrier signal results on the opposite end of the link.

Abstract: The present technique relates to a receiving device that can promptly present receivable one-segment broadcasts, a receiving method, and a program. Station information acquiring units (111 through 113) acquire area broadcast information about stations that transmit broadcast waves of arbitrary one-segment broadcasting through arbitrary segments. Using the area broadcast information, a station selecting unit (117) selects stations of one-segment broadcasts receivable at a predetermined location as selectable stations that can be selected by tuning. A tuning control unit (118) performs tuning control to select a one-segment broadcast of a selectable station. The present invention can be applied to mobile one-segment broadcast receiving terminals, for example.

Abstract: Embodiments provide a digital RF receiver including a signal converting unit which converts an RF signal received from an external device into a digital signal, a plurality of functional modules which processes the digital signal in accordance with a predetermined algorithm when the digital signal is input, and a signal processing controller which selects at least one of the plurality of functional modules to control the digital signal to be processed in consideration of whether an IF signal component is included in the digital signal or a sampling rate related with sampling information of the digital signal.

Abstract: A system and method for classifying a channel with regard to delay spread in a wireless network applying orthogonal frequency division multiplexing. In one embodiment, a wireless receiver includes a channel classifier. The channel classifier is configured to compute a channel estimate corresponding to a channel traversed by a packet received by the wireless receiver. The channel classifier is also configured to partition the channel estimate into a plurality of windows. Each window corresponds to a range of time of the channel estimate. The channel classifier is further configured to assign a delay spread classification to the channel based on a distribution of energy across the windows.

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 method of receiving a demodulated waveform according to a protocol in which the waveform represents a block of transmitted bits comprising a first group of bits and a second group of bits, the second group of bits being a function of the first group of bits, the method comprising: sampling the demodulated waveform to recover a first group of sample values corresponding to the first group of transmitted bits and a second group of sample values corresponding to the second group of transmitted bits; assigning bit values to reliable sample values of the first group of sample values; generating a set of candidates for a block of bits corresponding to the demodulated waveform, each candidate comprising a first group of candidate bits and a second group of candidate bits, the first group of candidate bits being generated using the assigned bit values and a combination of bit values unique to that candidate in the set of candidates, and the second group of candidate bits being generated by applying the said functio

Abstract: A detector receives detects a first known signal in a packet signal. An LTF correlation unit performs correlation processing on the packet signal received by a receiving unit. Upon detecting the arrival timing, an update correlation unit terminates a first window and performs correlation processing on the packet signal received by the receiving unit, in a second window. When correction timing is detected and when correction timing is more likely to be accurate than the arrival timing, an estimation unit changes the correction timing to the arrival timing; when the arrival timing is more likely to be accurate than the correction timing, the estimation unit maintains the arrival timing.

Abstract: In UWB communication based on an MB-OFDM communication scheme, when a jamming interference is detected within a receiving frequency band, the frequency of a local signal LO is altered to a frequency that will cause the jamming to be converted to a frequency outside the pass band of an LPF.

Abstract: Digital television broadcasting signals employ parallel concatenated convolutional coding, commonly called “turbo coding”, to improve reception by receivers in motor vehicles. Turbo coded Reed-Solomon codewords are transversally disposed in the payload fields of encapsulating MPEG-2-compliant packets to improve the capability of the Reed-Solomon coding to overcome deep fades. Turbo codewords are transmitted more than once in so-called “staggercasting”. Reception of DTV signals is improved by combining soft decisions concerning repeated transmissions of turbo codewords before turbo decoding. Only the data components of turbo codewords are transmitted twice in “punctured” staggercasting of turbo codewords, with parity components being transmitted only once, so code rate is reduced by a smaller factor than two.

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: Provided are a transmitter and a method for transmitting a data block in a wireless communication system. The method comprises the following steps: encoding an information bit and generating a block coded with an NCBPSS bit; generating two sub-blocks by parsing the coded block; and transmitting the two sub-blocks to the transmitter. By preventing the bits that are contiguous to the encoding block from having continuous identical reliabilities on a signal constellation, the deterioration of the decoding performance of the transmitter can be prevented.

Abstract: A specialized preamble is provided to facilitate matrix channel estimation of a MIMO channel. In a particular implementation, a channel training preamble provided by the IEEE 802.11a standard is modified to facilitate MIMO channel estimation.

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: An apparatus for performing sequence detection on a stream of incoming bits comprises a memory and circuitry coupled to the memory. The circuitry is operative, for each bit of the stream of incoming bits, to overwrite a first binary number presently stored in the memory with a second binary number, and to provide an output indicative of when the second binary number is equal to a predetermined value. The output indicative of when the second binary number is equal to the predetermined value is, in turn, indicative of when a binary number constructed by the stream of incoming bits is divisible by a prescribed integer.

Abstract: A transmitter module for unidirectional communication with a receiver module and a method using the aforementioned. The transmitter module includes a carrier detection portion, a source processing portion coupled to the carrier detection portion and a source transmission portion coupled to the source processing portion. The source processing portion can receive and process an information signal to produce a processed information signal in a manner such that an appropriate carrier signal is modulated with the information signal. The appropriate carrier signal can be based on the detection signals communicated from the carrier detection portion. The source processing portion can further process the information signal in a manner such that the processed information signal is associable with at least one of a unique code and an indication signal. The indication signal is associable with absence of communication of the at least one communication signal in a communication medium.

Abstract: An antenna beam scan unit includes: a Rotman lens that performs power division and synthesis between plural antenna ports and three or more beam ports; plural antenna elements which are connected to the respective antenna ports and to or from which radio waves are inputted or outputted; plural amplifiers that are connected to the respective beam ports of the Rotman lens and perform amplitude modulation on a signal; input paths for a transmission signal disposed in association with the amplifiers; switches for switching the input paths; and a beam control unit. The input paths include first paths and second paths on which a signal that is out of phase with a signal on the first paths is produced. The beam control unit selects two adjoining beam ports, and can switch the first paths and second paths as the input paths for the two beam ports.

Abstract: In a wireless communication system including a transmitter device and a receiver device used for transmission of wireless signals having a plurality of sub-carriers, the transmitter device performs error correction coding on transmitting data and selects at least one of the plurality of sub-carriers used for transmission of error-correction coded data as a null sub-carrier having zero amplitude, thus transmitting the error-correction coded data, while the receiver device receives signals having the plurality of sub-carriers from the transmitter device so as to retrieve original transmitted data by implementing error correction decoding on received signals, thus determining whether an interference wave occurs in the sub-carrier upon detecting reception power exceeding a predetermined threshold in the sub-carrier serving as the null sub-carrier.

Abstract: Systems and methodologies are described herein that facilitate improved modulation and coding techniques for a multiple-in multiple-out (MIMO) communication system. As described herein, data to be transmitted over a set of physical layers (e.g., corresponding to antennas, beams, etc.) can be processed such that encoding is performed on a per-codeword basis and modulation is performed on a per-layer basis, thereby mitigating performance degradation experienced by traditional systems due to layer imbalance. As further described herein, per-codeword code rate parameters and per-layer modulation parameters can be signaled to a device in various manners, such as through modulation and coding scheme (MCS) signaling, explicit code rate and/or modulation scheme signaling, relative code rate and/or modulation scheme signaling, or the like.

Abstract: A method of encoding an audio signal, where signals including two or more channel signals are downmixed to a mono signal, the mono signal is divided into a low-frequency signal and a high-frequency signal, the low-frequency signal is encoded through algebraic code excited linear prediction (ACELP) or transform coded excitation (TCX), and the high-frequency signal is encoded using the low-frequency signal. A method of decoding of an audio signal, a low-frequency signal encoded through ACELP or TCX is decoded, a high-frequency signal is decoded using the low-frequency signal, the low-frequency signal and the high-frequency signal are combined to generate a mono signal, and the mono signal is upmixed by decoding spatial parameters regarding signals including two or more channel signals.

Abstract: A method for digital compensation of a nonlinear system comprises identifying a plurality of circuit parameters of a nonlinear system. Each circuit parameter determines a nonlinear response of the nonlinear system. A first circuit parameter is chosen from the plurality of circuit parameters. The first circuit parameter determines a first effect on the nonlinear response. The first effect is at least as large a second effect from a second circuit parameter from the plurality of circuit parameters. At least one stimulus is applied to the nonlinear system. The nonlinear response of the nonlinear system is measured in response to the at least one stimulus. A compensation architecture is synthesized to substantially linearize the nonlinear response. The compensation architecture receives the nonlinear response of the nonlinear system and provides a substantially linear response.

Abstract: An apparatus and method for compressive sensing tap identification for channel estimation comprising identifying a set of significant taps in the time domain; representing a time-flat channel response using a Taylor series expansion with the set of significant taps; converting the time-flat channel response to a vectorized channel response; transforming the vectorized channel response to a compressive sensing (CS) polynomial frequency response; aggregating the CS polynomial frequency response into a stacked frequency response; converting the stacked frequency response into a measured pilot frequency response; estimating a channel parameter vector based on the measured pilot frequency response; and generating a reconstructed channel response from the channel parameter vector.

Abstract: A system and a method for applying a blind tuning process to M antennas coupled via N beamformers to a multiple input multiple output (MIMO) receiving system having N channels, wherein M>N, are provided herein. The method includes the following steps: Periodically measuring channel fading rate at a baseband level to determine the number of antennas L out of K antennas connected to each one of the beamformers, to be combined at each one of the N beamformers; assigning the antennas to the subset L according to some criteria such as best quality indicator; repeatedly applying a tuning process to L antennas in each one of the N beamformers.

Abstract: A digital broadcast transmitter comprising: a randomizer to receive a data stream of which stuff bytes are inserted into a specified position and to randomize the received data stream; a stuff-byte exchange unit to generate known data having a predefined pattern and to insert the known data into the specified position of the data stream into which the stuff bytes are inserted; an encoder to encode the data stream output from the stuff-byte exchange unit for an error correction; and a modulator and RF converter to modulate the encoded data stream, RF-convert the modulated data stream and transmit the RF-converted data.

Abstract: A digital broadcast transmitter comprising: a randomizer to receive a data stream of which stuff bytes are inserted into a specified position and to randomize the received data stream; a stuff-byte exchange unit to generate known data having a predefined pattern and to insert the known data into the specified position of the data stream into which the stuff bytes are inserted; an encoder to encode the data stream output from the stuff-byte exchange unit for an error correction; and a modulator and RF converter to modulate the encoded data stream, RF-convert the modulated data stream and transmit the RF-converted data.

Abstract: A receiver system and method for recovering information from a symbol data sequence Y. The symbol data sequence Y corresponds to a symbol data sequence X that is transmitted onto the channel by a transmitter. The symbol data sequence X is generated by the transmitter based on associated information bits. At the receiver, a set of two or more processors operate in parallel on two or more overlapping subsequences of the symbol data sequence Y, where each of the two or more overlapping subsequences of the symbol data sequence Y corresponds to a respective portion of a trellis. The trellis describes redundancy in the symbol data sequence Y. The action of operating in parallel generates soft estimates for the associated information bits. The soft estimates are useable to form a receive message corresponding to the associated information bits.

Abstract: A method is provided for searching for a pairing PMI including estimating a MIMO wireless propagation channel from an access point transmitter to a receiver at a UE; quantizing the estimated channel with a codebook consisting of a plurality of codewords, the result being an actual SU-MIMO PMI currently applicable to the UE; estimating the channel quality corresponding to the actual SU-MIMO PMI, resulting in at least one CQI for the UE; constructing a plurality of subsets from a codebook of codewords, wherein each subset comprises potential MU-MIMO PMIs that represent channels that have reduced interference with a channel represented by one of the potential SU-MIMO PMIs; associating each potential SU-MIMO PMI with the subset that comprises the potential MU-MIMO PMIs that represent channels that have reduced interference with the channel represented by that potential SU-MIMO PMI; searching for an appropriate pairing PMI and the associated CQI for the UE.

Abstract: A method for beamforming in a multiple input, multiple output (MIMO) communication system includes receiving a non-sounding data unit, where the non-sounding data unit does not include an indication that the data unit is for estimating a MIMO communication channel, developing an estimate of a reverse channel in which the non-sounding data unit travels based on the non-sounding data unit, developing an estimate of a forward channel based on the estimate of the reverse channel, and developing a steering matrix to perform beamforming in the forward channel based on the estimate of the forward channel.

Abstract: In one embodiment, a method can provide for dynamic updating of slope values used in determining a soft decision for a demodulated signal obtained in a receiver from a broadcast signal received by the receiver. The method includes generating a channel estimate for a channel traversed by the signal, computing channel state information from the channel estimate, computing statistical information from the channel state information, determining a slope value based at least in part on the statistical information, calculating a log-likelihood ratio (LLR) value for the signal, and applying the slope value to the LLR value to obtain a weighted LLR value.

Abstract: A method includes receiving a signal including first data precoded on the basis of a first codebook entry of a codebook, wherein the codebook includes at least one further codebook entry, averaging a set of matrices to obtain a mean matrix wherein each matrix of the set of matrices is determined on the basis of a respective other codebook entry of the at least one further codebook entry and determining a covariance matrix on the basis of the mean matrix.

Abstract: The present invention discloses a reception circuit capable of enhancing accuracy of signal reception. The reception circuit includes a variable termination resistance unit, coupled to at least one channel, for utilizing at least one termination resistance corresponding to the at least one channel to perform impedance matching, a receiver, coupled to the at least one channel, for receiving a calibration signal to generate a digital calibration signal, and a data determination control unit, for comparing the digital calibration signal with a predefined data, to adjust the at least one termination resistance.

Abstract: In one embodiment, receiving an Ethernet signal over a channel, the Ethernet signal comprising a preamble frame, an idle frame, and a data frame, the preamble frame comprising one or more preamble codes; synchronizing to the Ethernet signal based on the preamble frame; replicating the one or more preamble codes; and training a decision feedback equalizer (DFE) based on the one or more replicated codes, the training enabling the DFE to use decision values at the DFE output to track channel variations.

Abstract: An apparatus for communicating data.

Abstract: A digital broadcast transmitter comprising: a randomizer to receive a data stream of which stuff bytes are inserted into a specified position and to randomize the received data stream; a stuff-byte exchange unit to generate known data having a predefined pattern and to insert the known data into the specified position of the data stream into which the stuff bytes are inserted; an encoder to encode the data stream output from the stuff-byte exchange unit for an error correction; and a modulator and RF converter to modulate the encoded data stream, RF-convert the modulated data stream and transmit the RF-converted data.

Abstract: One embodiment of the present invention relates to an analog correlation unit comprising a plurality of parallel correlation components configured to operating according to an advanced switched-capacitor low pass filter principle that increases coding gain of the unit. Each correlation component comprises a sampling stage and a correlation stage. The sampling stage may comprise a switched capacitor configured to sample a received baseband signal to determine a value (e.g., polarity) of the baseband signal. The sampled baseband signal is provided to the correlation stages, which may respectively comprise a plurality of switched integrators configured to selectively receive and integrate the sampled baseband signal over time depending upon values (e.g., polarity) of the correlation code to generate voltage potential values. The analog correlation result is evaluated by a comparison of an adjustable threshold voltage with the difference between the output voltage potential values.

Abstract: In accordance with an embodiment, a method includes determining an amplitude of an input signal provided by a capacitive signal source, compressing the input signal in an analog domain to form a compressed analog signal based on the determined amplitude, converting the compressed analog signal to a compressed digital signal, and decompressing the digital signal in a digital domain to form a decompressed digital signal. In an embodiment, compressing the analog signal includes adjusting a first gain of an amplifier coupled to the capacitive signal source, and decompressing the digital signal comprises adjusting a second gain of a digital processing block.

Abstract: An object of the present invention is to provide a data communication technique which can reduce a size of a system by enabling bidirectional data communication, and enables a cheap system configuration.

Abstract: A method and an apparatus for estimating an offset are provided. The method includes determining one of a frequency offset and a timing offset to be estimated first for pilot symbols detected from a received signal, estimating one of the frequency offset and the timing offset for the pilot symbols according to the determination, compensating for an offset of the pilot symbols based on the estimated offset, and estimating remaining one of the frequency offset and the timing offset which is not estimated for the offset compensated pilot symbols.

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 channel state information compressing apparatus includes a time-to-frequency region converter that converts a region for channel state information which indicates a state of each communication channel from a time region to a frequency region; and an adaptive selector that selects each frequency component to be included in compressed data based on electric power of the frequency component from among frequency region data obtained by the time-to-frequency region converter. The channel state information compressing apparatus outputs the compressed data consisting of each selected frequency component, and information for identifying each frequency component which forms the compressed data.