Abstract: A system for implementing an orthogonal frequency division multiplexing scheme and providing an improved range extension. The system includes a transmitter for transmitting data to a receiver. The transmitter includes a symbol mapper for generating a symbol for each of a plurality of subcarriers and a spreading module for spreading out the symbol on each of the plurality of subcarriers by using a direct sequence spread spectrum. The symbol on each of the plurality of subcarriers is spread by multiplying the symbol by predefined length sequences. The receiver includes a de-spreader module for de-spreading the symbols on each of the plurality of subcarriers. The de-spreader module includes a simply correlator receiver for obtaining maximum detection. The correlator produces an output sequence of a same length as an input sequence and the de-spreader module uses a point of maximum correlation on the output sequence to obtain a recovered symbol.

Abstract: A low complexity RACH preamble detector is described herein. The RACH preamble detection algorithm uses the peak detection of the time domain correlation function through frequency domain processing. The frequency domain processing considers the reference signals generated directly from frequency domain CAZAC sequence or time domain CAZAC sequence with DFT conversion. A low-complexity poly-phase LPF along with down sampling is implemented before the FFT to reduce the required length of the long FFT operation N-folded.

Abstract: A receiver for receiving a data signal having a channel profile may include an equalizer, to which the data signal is feedable, the equalizer having a plurality of filters and a switching device coupled to the filters, a selection device, which is disposed such that it determines a first number and a second number in dependence on the channel profile, and the switching device is disposed such that it connects a number of linear filters corresponding to the first number to form a first overall filter and connects a number of linear filters corresponding to the second number to form a second overall filter.

Abstract: A method and apparatus for reconfiguring a GPS receiver. A device in accordance with the present invention comprises a Radio Frequency (RF) section, the RF section adaptable to receive at least one GPS signal from at least one GPS satellite; and a baseband section, coupled to the RF section, the baseband section comprising at least one correlator, wherein the at least one correlator is adaptable to reacaquire the at least one GPS signal based on a priori knowledge of the at least one GPS signal.

Abstract: Method and apparatus are provided for estimating noise variance using a long-term data aided algorithm and an interference variance using a short-term data aided algorithm. Using these estimations, an interference hypothesis may be determined. Some embodiments compute the variance for a decision directed noise sample, convert the variance for the decision directed noise to a true noise variance per packet, and convert the variance for the decision directed noise to a true noise variance per symbol. The interference hypothesis may be based on the noise variance estimations per symbol and the noise variance estimation per packet. Some embodiments determine the presence of noise based on a comparison of the noise variance per packet, the noise variance per symbol, and each hypothesis and compute the long-term noise variance. Using the long-term noise variance in place of the variance for a decision directed noise sample for a subsequent determination of interference.

Abstract: An inter-carrier interference ICI cancellation method of a kth sub-carrier of an orthogonal frequency division multiplexing OFDM receiving signal (k is a natural number greater than 1 and less than or equal to n, n is a number of sub-carriers) includes canceling an inter-carrier interference element produced by at least one sub-carrier among inter-carrier interference elements of the kth sub-carrier by a decision feedback equalization DFE method, and canceling another inter-carrier interference element produced by at least another sub-carrier among inter-carrier interference elements of the kth sub-carrier by a linear minimum mean square error equalization LMMSE method.

Abstract: A system including an estimation module, a processing module, and a control module. The estimation module is configured to generate a first set of channel estimates for a plurality of subcarriers of a received signal. The processing module is configured to generate a second set of channel estimates for the plurality of subcarriers, in which the second set of channel estimates are generated based on the first set of channel estimates. The control module is configured to estimate a preamble sequence in the received signal based on each of (i) the first set of channel estimates and (ii) the second set of channel estimates.

Abstract: In a method and a device for decoding a signal, the signal is transmitted via at least one connecting line of a data transmission system, in a user of the data transmission system receiving the signal. It is provided to measure the interval of a change—provided compulsorily in a transmission protocol used in the data transmission system—of the signal from rising to falling or from falling to rising edge. A tendency for an asymmetrical delay of the signal can be ascertained from the measured interval. The sampling of the bits of the received signal can be improved as a function of the interval or of the asymmetrical delay, for example, by setting the sampling instant in variable fashion. Alternatively, the interval or the asymmetrical delay can be utilized for diagnostic purposes.

Abstract: Embodiments provide techniques for high peak to average power ratio (PAPR) event mitigation in high speed data networks, such as cable networks, for example. Embodiments are applicable to multi-carrier and single-carrier modulation systems. Embodiments operate by predicting or detecting the occurrence of a peaking event at the transmitter, and then mitigating potential effects of the peaking event at the transmitter, including application of alternative constellation symbol mappings.

Abstract: A computationally-simplified approach to expected symbol value determination is based on classifying soft bit information corresponding to symbols in a received communication signal as being reliable or unreliable, and computing expected symbol values for the symbols based on the classified soft bit information. Classification can be carried out by “quantizing” the soft bit information to coarsely indicate whether individual symbol bits are known with high or low probability. Using quantized soft bit information greatly simplifies expected symbol value calculation, yet the calculated values still reflect a scaling corresponding to the underlying reliability of the soft bit information.

Abstract: In accordance with some embodiments, receivers for receiving a wireless data transmission are provided, the receivers comprising at least one amplifier that receives an RF input signal and produces at least one amplified signal; a mixer that mixes the at least one signal to produce a mixed signal; a filter that filters the mixed signal to produce a filtered signal, a comparator that compares the filtered signal to a threshold voltage and produces a digital signal, a first pulse generate i that generates a first pulse in response to a transition in the digital signal, a second pulse generator that generates a second pulse that is longer than the first pulse in response to a transition in the digital signal; and digital logic that generates a clock output and that generates a data output based on a state of the first pulse when the second pulse expires.

Abstract: A signature sequence is employed in a wireless transmission over a channel and is detected by a receiving station. The signature sequence is selected from a subset of sequences chosen from a set of sequences formed by delay-Doppler shifts of a base sequence. Use of the subset of sequences simplifies detection of the signature sequence by, e.g., facilitating use of a simpler detector structure. A subset of N2 sequences of the specially-constructed delay-Doppler shifted sequence set is selected to facilitate more efficient computation of the detection metric. A simplified detector employs algebraic techniques (such as Discrete Fourier 'Transform (DFT)) that exploit prudent sequence assignment strategy. As an advantageous variation, for a particular class of base sequences that can be represented by segments of equal-length sinusoids, even greater complexity reduction can be achieved by segmenting the delay-Doppler correlation accordingly and reusing past outcome in subsequent overlapping segments.

Abstract: A symbol clock recovery circuit is provided for a data communication system using coherent demodulation. The symbol clock recovery circuit comprises an analog-to-digital converter comprising a first input for receiving a coherent-detected baseband analog signal derived from a carrier signal, a second input for receiving an adapted symbol clock signal, and an output for outputting a digital signal comprising a frame having a preamble with at least two symbols. The symbol clock recovery circuit comprises further a phase shifting unit comprising a first input for receiving a symbol clock signal derived from the carrier signal, and a timing detector, comprising a first input for receiving the digital signal from the analog-to-digital converter and an output for providing a signal comprising information about an optimum sample phase to the phase shifting unit.

Abstract: Embodiments of the present technology recite a method and system for maintaining integrity of a binary offset carrier (BOC) signal. In one embodiment, a first correlator is configured for multiplying a timing signal with an internally generated pseudo-random noise (PRN) signal to create a reference signal. The first correlator is further configured for combining the reference signal with a received PRN signal and outputting a first correlation function based upon the combining. A second correlator is configured for multiplying the internally generated PRN signal with the received PRN signal and for outputting an integrity correlation function. A comparison component is configured for determining the offset of the reference signal relative to the received PRN signal based upon a comparison of the integrity correlation function with the first correlation function.

Abstract: A multi-sensor signal fusion apparatus is provided for automatic modulation classification of weak unknown signals in non-cooperative communication environment with a more accurate description of the signal. The multi-sensor non-cooperative demodulation device combines a group of sensors, a signal fusion sensor, a means for signal demodulation, and a means for automatic modulation classification. An output of the signal fusion sensor is sent to a means for modulation scheme classification to select the appropriate demodulation technique for demodulating the unknown signal and provide the necessary intelligence about the monitored signals to the user and allow the user to simulate the unknown non-cooperative signal.

Abstract: The invention relates to a method of estimating symbols carried by a digital signal that is received by a receiver over a communication channel (5), said symbols being multiplexed or orthogonal frequency sub-carriers. The inventive method comprises the following steps in relation to each symbol carried by the digital signal, consisting in: performing at least two transforms towards the frequency domain (8,9) on a portion of the received signal essentially corresponding to the symbol, said transforms being performed with a determined time lag (10) therebetween: estimating the parameters (r0, r1, . . . , rn, r?0, r?1, . . . , r?n) of the communication channel from pre-determined binary information contained in the digital signal; and estimating the symbol from a combination of the result of each of the transforms performed and the estimated communication channel parameters.

Abstract: A wireless receiver including receiving antennas, frequency-space transformers, noise wave removers, a back-end signal processor, a pattern detector, a broadcast interruption detector, and a back-end controller. The frequency-space transformers convert signals received by the antennas into frequency-space signals. The noise wave removers each at least perform the calculation of a transmission line coefficient matrix and the calculation of an inter-antenna covariance matrix on the frequency-space signals. A controller controls the back-end signal processor to operate when the multicarrier transmission waves have been detected to be interrupted. The noise wave removers each perform the calculation of the inter-antenna covariance matrix when a broadcast interruption detector has detected the interruption of the multicarrier airwaves. Thus, the wireless receiver removes noise generated within it, thereby having high reception sensitivity.

Abstract: A method for transmitting information using a sequence is disclosed. According to an embodiment, the method includes the steps of generating a sequence for transmitting data or control signals, performing phase modulation for indicating additional information on partial elements among a plurality of elements configuring the sequence, and transmitting the phase modulated sequence.

Abstract: There is provided an information processing apparatus includes, an encoding section for encoding a bit string to generate a data signal having an amplitude of a1 and a transmission speed of b; a signal generation section for synchronously adding a clock having a frequency of b/K (K is a predetermined natural number), an amplitude of a2 (>a1), and a small duty ratio to the data signal generated by the encoding section to generate a transmission signal; and a signal transmission section for transmitting the transmission signal generated by the signal generation section.

Abstract: A system for synchronizing a receiver of a bit stream to the bit stream include a correlator to remove the PN code modulation and to generate a stream of time sequence values (samples) from the received bits. Multiple accumulators are included, each accumulator corresponding to a different offset from a first time period. The accumulators add a number of values equal to a number of samples in a bit period. Multiple magnitude calculators receive sums from the corresponding accumulators and calculates respective magnitudes. Multiple non-coherent summers are then used to add the magnitudes for each offset in each bit period for all of the received bits. The outputs of the non-coherent summers are analyzed to find the highest value, to identify the location of the bit transition in the bit period.

Abstract: A CDMA receiving apparatus includes a path searcher which outputs path timing that corresponds to sample timing where a correlation value between a received data sequence and a reference code sequence reaches a peak, and outputs the correlation value calculated at a sample timing adjacent to the path timing as an adjacent timing correlation value; an interpolation adjuster; and a despreader which despreads an output of the interpolation adjuster at the path timing, wherein the interpolation adjuster includes an interpolator for generating an interpolating data sequence which is a data sequence displaced in time by a specified fraction of one sample period with respect to the received data sequence, and outputs the received data sequence or the interpolating data sequence by switching therebetween based on a result of a comparison between the correlation value calculated at the path timing and the adjacent timing correlation value.

Abstract: A received signal determination method includes: receiving a positioning signal; performing correlation calculations on the received positioning signal using a code replica of one spreading code among the plurality of spreading codes; selecting a total peak value and a remote peak value, the total peak value being a first maximum correlation value among correlation values obtained by the correlation calculations, and the remote peak value being a second maximum correlation value among correlation values apart from a phase of the total peak value by a phase equal to or greater than a given phase; changing a threshold value condition for the total peak value based on the remote peak value; and determining whether or not the received positioning signal is spread-modulated with the one spreading code by determining whether or not the total peak value satisfies the threshold value condition.

Abstract: A code phase error estimating method includes calculating correlation for I and Q components of a reception signal, judging code phase based on the result of the correlation calculation; calculating a ratio of first difference to a second difference, where the first difference is a first correlation value minus a third correlation value and the second difference is a second correlation value minus the third correlation value, the first correlation value being a correlation value at the code phase, the second correlation value being a correlation value at a phase shifted from the code phase by X chip (0<X<1), and the third correlation value being a correlation value at a phase shifted from the code phase by Y chip (1<Y); and estimating the code phase error when the reception signal is a multipath signal.

Abstract: A first programmable frequency oscillator, which includes a first ramp comparator and programmable signal generation circuitry is disclosed. The programmable signal generation circuitry provides a ramping signal, which has a first frequency, based on a desired first frequency. The first ramp comparator receives the ramping signal and provides a first ramp comparator output signal based on the ramping signal. The first ramp comparator output signal is fed back to the programmable signal generation circuitry, such that the ramping signal is based on the desired first frequency and the first ramp comparator output signal. However, the first ramp comparator has a first propagation delay, which introduces a frequency error into the programmable frequency oscillator. Therefore, the first frequency is not proportional to one or more slopes of the ramping signal. As a result, the programmable signal generation circuitry compensates for the frequency error based on the desired first frequency.

Abstract: An analog type electronic timepiece including a plurality of hands for displaying a time; a driving unit for electrically driving the hands; a receiver for receiving and demodulating a radio wave containing a time code signal; and a second synchronization determination unit for determining a second synchronous point of the time code signal demodulated by the receiver through identifying a driving noise mixed in the time code signal by action of the driving unit.

Abstract: A method for determining a Doppler shift of a first signal is provided. First, a plurality of Doppler frequency hypotheses is combined to obtain a joint Doppler signal. The first signal is the correlated according to the joint Doppler signal and a plurality of code signals with phases corresponding to a series of code phase hypotheses to obtain a series of correlation results which are then examined to determine whether the Doppler shift does lie in the Doppler hypotheses. A fine Doppler search is then performed to determine the Doppler shift when the Doppler shift lies in the Doppler hypotheses.

Abstract: The invention relates to the acquisition of a code modulated signal, wherein a first set of correlation results for correlations between the code modulated signal and a first replica code with different code phases and a second set of correlation results for correlations between the code modulated signal and a second replica code with different code phases are available. In order to achieve a high sensitivity, results from both sets of correlation results are combined, wherein correlation results used in the combination are selected based on information on a relative difference between a correct code phase for both replica codes. Then, it is determined based on the combination whether at least one of the sets of correlation results comprises a correlation result representing the correct code phase for the first replica code or the second replica code, respectively.

Abstract: In a pulse-based communication system a transmitting device may generate a series of pulses to convey information via a communication medium to a receiving device. In some situations, interference from one or more interfering devices may alter the pulse energy as it is transmitted through the communication medium. To mitigate the effect of such interference, a receiving device may mark certain received pulses as erasures. In this way, such pulses may be ignored during the decoding operation of the receiver.

Abstract: A method and apparatus is provided for performing initial ranging at a receiver for establishing a time reference for a predefined received signature signal (30) for establishing a time reference overcoming round trip time between a receiver and a transmitter. There is performed (316, 3161) matched filtering in at least two matched sub-filters (M1, M2, M3, M4), each sub-filter having a matched filter sub-sequence (43—1, 2; 3, 4; 5,6; 7,8) corresponding to a fragment (39) of the basic sequence (33) of the predefined signature signal (30), wherein the fragments do not overlap one another with respect to the basic sequence, the matched filtering by each respective sub-filter providing peaks in dependence of the respective sub-sequence (43) correlating with a respective fragment of the received signature signal.

Abstract: Provided are an apparatus and method for measuring a carrier-to-interference and noise ratio (CINR) using a pilot symbol in a digital communication system, and more particularly, to an apparatus and method for measuring a CINR by estimating a data signal, noise, and an interference signal from a pilot symbol in a digital communication system using orthogonal frequency division multiplexing (OFDM)/orthogonal frequency division multiplexing access (OFDMA). The apparatus includes: a pilot symbol acquisition unit for acquiring the pilot symbol from a baseband frequency signal; a signal estimation unit for estimating a pilot signal and a data signal from the pilot symbol; a power calculation unit for calculating a power value of the estimated data signal and calculating a power value of a noise signal from a difference between the pilot symbol and an estimated pilot signal; and a CINR calculation unit for calculating a CINR on the basis of the power values of the data and noise signals.

Abstract: A method for blindly detecting a precoding matrix index used to transmit a data or control signal is provided. The method includes receiving at a mobile station (102) a common reference signal and user specific data and control signal weighted by precoding matrix. An objective function is applied to the received reference signal and user specific data and control signal that minimizes the objective function for each of at least one rank used to transmit the received user specific data and control signal and each of known possible modulation constellations used to transmit the received data/control signal to determine the precoding matrix index (PMI).

Abstract: A communication receiver and a receiving method are disclosed. An analog front-end device samples a receiving signal and generates a sampled signal. A signal detector detects presence of the receiving signal according to the sampled signal. A symbol timing recovery (STR) unit determines an optimal symbol sampling point according to a zero-crossing point of the sampled signal when the receiving signal is present, and then generates a recovered symbol based on an optimally chosen sampled value according to the optimal symbol sampling point.

Abstract: Methods and systems are provided for aging EV-DO pages in a queue based on latency-sensitivity. An access node receives data for access terminals, and responsively generates pages and adds them to the back of a queue. The access node associates a respective aging value with any latency-tolerant pages. The access node transmits the pages in the queue, which involves: (a) assessing the pages on a first-in, first-out basis; (b) transmitting latency-sensitive pages when those pages reach the front of the queue; (c) sending latency-tolerant pages to the back of the queue (and incrementing their aging values) when those pages reach the front of the queue with an aging value that is less than a maximum-delay parameter; and (d) transmitting latency-tolerant pages when those pages reach the front of the queue with an aging value that is greater than or equal to the maximum-delay parameter.

Abstract: A filtering apparatus including: first and second filters used to filter inputted packets; a connection information register disposed in correspondence with the first filter; a condition storage portion configured to store a filter condition for identifying a packet associated to the second filter; a reference number register configured to allocate any one of the numbers of the second filters as a reference number for each number of the first filter and to store the reference numbers; and a determination portion configured to determine the number of the second filter to be used to filter packets filtered using the first filter based on the reference number and on a value of the connection information register corresponding to the first filter.

Abstract: A receiver device for receiving a signal that comprises one or more periodic features, the receiver device comprising: a detector configured to listen to the signal during at least a first reception phase, and to be triggered when a feature of the signal is received so as to determine the time of reception of that feature; and a receiver configured to process time-limited segments of the signal so as to derive information from features of the signal received during those segments, the receiver being configured to be dependent on the detector such that after the first reception phase the timings of the time-limited segments processed by the receiver are dependent on the time of reception determined by the detector.

Abstract: A configurable all-digital coherent demodulator system for spread spectrum digital communications is disclosed herein. The demodulator system includes an extended and long code demodulator (ELCD) coupled to a traffic channel demodulator (TCD) and a parameter estimator (PE). The demodulator also includes a pilot assisted correction device (PACD) that is coupled to the PE and the TCD. The ELCD provides a code-demodulated signal to the TCD and the PE. In turn, the TCD provides a demodulated output data signal to the PE. The PACD corrects the phase error of the demodulated output data based on an error estimate that is fed forward from the PE. Accumulation operations in the ELCD, TCD, and PE are all programmable. Similarly, a phase delay in the PACD is also programmable to provide synchronization with the error estimate from the PE.

Abstract: Method and receiver synchronizing receiver with received ambiguous signal having at least two peaks. Method includes providing information about known transmitted signal having a number of at least two peaks, the information including number of peaks and distances between at least two peaks, determining ratios between peaks of known transmitted signal and assigning determined ratio value to each peak, and deducing theoretical auto-correlation function from known transmitted signal. Auto-correlation function has number of correlations corresponding to number of peaks in known transmitted signal and correlators of the auto-correlation function are provided in same distance and have the same relative ratio as peaks in known transmitted signal.

Abstract: A method and apparatus for matching compressed video data under a wireless fading environment are disclosed. The apparatus includes an encoder for encoding and outputting the video data as a compressed bit stream, a channel error measurement unit for measuring Signal-to-Noise Ratio (SNR) or Carrier-to-Noise Ratio (CNR) of a wireless channel, and an encoder optimization module for determining if the current fading is slow fading or fast fading. A control signal is output to reduce a frame transmission ratio or to change the quality of the vide data if it is determined that the current fading is slow fading. Another control signal is output to adjust the size of a data output buffer of the wireless channel if it is determined that the current fading is fast fading.

Abstract: A single chip radio transceiver includes circuitry that enables detection of radar signals to enable the radio transceiver to halt communications in overlapping communication bands to avoid interference with the radar transmitting the radar pulses. The radio transceiver is operable to evaluate a number of most and second most common pulse interval values to determine whether a traditional radar signal is present. The radio transceiver also is operable to FM demodulate and incoming signal to determine whether a non-traditional radar signal such as a bin-5 radar signal is present. After FM demodulation, the signal is averaged wherein a substantially large value is produced for non-traditional radar signals and a value approximately equal to zero is produced for a communication signal that is not FM modulated with a continuously increasing frequency signal. Gain control is used to limit incoming signal magnitude to a specified range of magnitudes.

Abstract: A receiver receives a received signal from a communication link, the received signal comprising a stream of symbols modulated onto a carrier, each of the stream symbols selected from a constellation of symbols to represent a plurality of encoded data bits. The receiver comprises a demodulator to produce a stream of received symbols derived from the received signal; a channel decoder to produce a received stream of data bits derived from the stream of received symbols; and a memory device to store information related to the plurality of symbols in the constellation.

Abstract: An RF receiver comprises a signal processor arranged to perform a method of decoding data contained within a signal that comprises a set of slots, at least one said slot comprising a preamble portion and a payload portion and being transmitted at a predetermined transmission frequency. The signal processor is arranged to perform a first process to derive timing data from the preamble portion and perform a second process to extract information from the payload portion, the second process being triggered from said timing data derived from the first process. The preamble portion comprises at least a first sequence of data and a second sequence of data, and the second sequence is the inverse of the first sequence. In preferred embodiments the first process comprises identifying a transition between said first and second sequences of data and deriving said timing data from the identified transition.

Abstract: The invention relates to method and device for detecting propagation paths in pulse transmission, wherein a received signal comprises pulses on each time symbol. After synchronizing a pulse-based reception, the inventive method consists (A) in determining the arrival times of pulses of the same current time symbol, (B) in generating a path hypotheses by assigning an initial score to each dated pulse, (C) in determining the arrival times of pulses of the time symbol following the current symbol, (D) in relatively comparing the arrival times of pulses of the following time symbol with the arrival times of the path hypotheses and (E) in updating scores according to the relative comparison results. Said path detecting method is suitable for pulse information transmission, in particular in UWB.

Abstract: A method for conserving bandwidth in a communication system includes spreading a data frame using a first pseudo-noise (PN) spreader. A broadcast frame is spread using a second PN spreader. A complex data stream having a first component and a second component is generated. The data frame is assigned to the first component and the broadcast frame is assigned to the second component. The complex data stream is transmitted to a tag.

Abstract: A method for extracting time information from a received, amplitude-modulated time signal is provided. The method provides that the time signal is demodulated, the analog signal thus obtained is digitized by a comparator, and the digital signal thus obtained is analyzed to extract the time information. In addition, a characteristic value of the time duration of at least one signal phase of a specific signal level of the digital signal is compared to a target value, and a comparator threshold of the comparator is altered as a function of a result of the comparison such that the time duration of at least the applicable signal phase of the digital signal approaches the target value. In this way, an improved system sensitivity is achieved according to the invention in a receiver for receiving time signals.

Abstract: By assigning a plurality of subcarriers 31 to a data channel 33 and assigning fewer subcarriers 32 than the plurality of subcarriers 31 to a control channel 34 and, in addition, locating the control channel 34 at the center frequency fc of a frequency band used to transmit the data channel 33, on the radio receiving apparatus side, the frequencies of a local signal by which the received signal is multiplied share the same value, thereby speeding up the switching between the control channel and the data channel.

Abstract: A method for determining transfer rate comprising selecting a first transfer rate of a plurality of transfer rates, transmitting a message at the first transfer rate over a Consumer Electronics Control (CEC) line of a High Definition Multimedia Interface (HDMI) network, determining whether an acknowledgment to the message having been transmitted at the first transfer rate is received, storing, in the event the acknowledgment to the message having been transmitted at the first transfer rate is received, the first transfer rate and storing, in the event no acknowledgment is received, a default transfer rate of the plurality of transfer rates.

Abstract: A modulation scheme estimation apparatus includes a receiving unit receiving a first signal, a generation unit generating a plurality of first phase amounts, an acquisition unit acquiring a plurality of multiplication signals by multiplying the first signal by each of the first phase amounts, an extraction unit extracting a plurality of second signals corresponding to respective direct-current components of third signals obtained by subjecting the multiplication signals to Fourier transform, a first computation unit computing a plurality of sums, each of which is a sum of each of the multiplication signals and a corresponding one of the second signals, a second computation unit computing a plurality of absolute values of the sums, and a first identifying unit identifying a modulation scheme corresponding to one of the absolute values which has a highest similarity with respect to reference values associated with modulation schemes.

Abstract: Apparatus and methods for use in a wireless communication system are disclosed for determining a timing position for channel activity in order to resolve timing ambiguity. A disclosed apparatus includes a processor that determines when channel activity occurs in at least one of an early or a late arrival position in a communication channel estimate and unwraps the channel activity in either the early arrival position or the late arrival position to a corresponding late or early arrival unwrapped channel activity position in the wireless channel estimate. The processor correlates symbol data in the communication signal corresponding to both the channel activity and the unwrapped channel activity to symbol data of the main channel activity. The processor determines whether a correct timing position of the channel activity is one of the early or late arrival positions based on the correlations, thus resolving timing ambiguity. Complementary methods are also disclosed.

Abstract: The invention provides a method and an apparatus for determining a skew of each data bit of an encoded data word received by a receiver via an interface from a transmitter comprising the steps of performing an error check and correction of the received and sampled encoded data word to calculate an error corrected encoded data word corresponding to the encoded data word transmitted by the transmitter, and correlating a sequence of error corrected encoded data words with the sampled encoded data words to determine a skew of each data bit of said received encoded data words.

Abstract: In a high-precision signal detection apparatus and method for a high-speed receiver, signal detection occurs asynchronously of the incoming data. A comparison clock is generated by an oscillator whose effective capacitance is varied by a second, lower speed oscillator connected to the capacitance. This prevents the asynchronous sampling that occurs in a zero-crossing position in the incoming data from remaining in that position in subsequent sampling cycles, so that a valid signal is not missed by the detector.