Abstract: An orthogonal-frequency division multiplexed (OFDM) transmitter is configured to transmit a data unit in accordance with a multiple-input multiple-output (MIMO) technique over a wideband channel comprising a 20 MHz channel and another channel using a plurality of spatially diverse antennas. The transmitter is further configured to include in the data unit, a parameter indicating a modulation and coding scheme and a parameter indicating number of spatial streams. Each of the spatial streams is encoded and beamformed for receipt by one or more different receiving stations.

Abstract: In one embodiment, a method includes receiving a radio frequency (RF) signal; synchronizing the received RF signal with a preamble to determine a time base; determining a first energy value of the received RF signal by averaging received signal strength indication (RSSI) values of the received RF signal over a first period of time; determining a second energy value of the received RF signal over a second period of time; determining a difference value between the first energy value and the second energy value; comparing the difference value with a predetermined energy threshold value; determining a quality value of the received RF signal; comparing the quality value of the received RF signal with a predetermined quality threshold value; and, if the difference value exceeds the predetermined energy threshold value or the quality value is below the predetermined quality threshold value, then erasing the time base.

Abstract: A wireless receiving apparatus includes a spurious component extraction unit, and a spurious cancellation unit. The spurious component extraction unit is configured to cancel a desired wave with a multi-antenna configuration, and extract spurious components. The spurious cancellation unit is configured to cancel spurious in received signals by using the spurious components extracted. A first correlation unit in the spurious component extraction unit finds a correlation between an output of the spurious extraction unit and an output of the spurious cancellation unit.

Abstract: A receiver may process a received signal to generate a processed received signal. The receiver may generate, during a sequence estimation process, an estimate of a phase error of the processed received signal. The receiver may generate an estimate of a value of a transmitted symbol corresponding to the received signal based on the estimated phase error. The generation of the estimate of the phase error may comprise generation of one or more phase candidate vectors. The generation of the estimate may comprise calculation of a metric based on the one or more phase candidate vectors. The calculation of the metric may comprise phase shifting the processed received signal based on the estimated phase error resulting in a phase-corrected received signal. The calculation of the metric may comprise calculating a Euclidean distance based on the phase-corrected received signal and one or more symbol candidate vectors.

Abstract: A method for time delay estimation performed by a physical computing system includes passing a first input signal obtained by a first sensor through a filter bank to form a first set of sub-band output signals, passing a second input signal obtained by a second sensor through the filter bank to form a second set of sub-band output signals, the second sensor placed a distance from the first sensor, computing cross-correlation data between the first set of sub-band output signals and the second set of sub-band output signals, and applying a time delay determination function to the cross-correlation to determine a time delay estimation.

Abstract: A method of WLAN frame detection in a received signal, wherein the frame comprises first and second training sequences and the method comprises auto-correlating the signal with a delayed version of itself to establish a first frame boundary estimate based on behavior of the autocorrelation result due to the inclusion of the first training sequence in the frame, cross-correlating the signal with a copy of the second training sequence at a range of time offsets in order to generate a first cross-correlation profile, classifying the first cross-correlation profile into one of a number of categories, establishing a second frame boundary estimate from the first cross-correlation profile in a manner dependent upon the category assigned to the first cross-correlation profile and determining a refined frame boundary estimate on the basis of a consideration of the first and second frame boundary estimates. Apparatus for performing the method is also described.

Abstract: Techniques are described herein that receive communications transmitted according to different operation modes at a multi-mode, programmable receiver system. The multi-mode, programmable receiver system may receive communication signals from transmit antennas in “cells” (e.g., base station transceivers and/or the like) according to one or more operation modes, using receive antennas. The received signals may be converted and processed by various modules of the multi-mode, programmable receiver system to produce an output signal. The multi-mode, programmable receiver system includes modules that are programmable to be selectively enabled or disabled according to an operation mode in accordance with which the multi-mode, programmable receiver system operates.

Abstract: The present invention discloses a method for implementing automatic frequency control, and an apparatus thereof. The method discloses: calculating a correlation value of common pilot symbols in a reception signal of each path and a frequency offset value, calculating a combined frequency offset value according to the frequency offset value of each path, and determining, according to the combined frequency offset value, a frequency offset adjustment value for a voltage controlled oscillator, a frequency offset adjustment value for overall reception signals and a frequency offset adjustment value for the reception signal of each path. The present invention selects a method of small-scope frequency offset estimation, which makes frequency offset estimation more accurate.

Abstract: A method and apparatus for building a long range RFID system is disclosed. A new signaling structure called Block Pseudo Noise is described that allows for more computationally efficient decoding. A novel approach to synchronize the RFID reader local oscillator with the RFID tag oscillator using an on board GPS receiver on the RFID tags and RFID reader is also disclosed. A novel positioning technique called Asynchronous Time Difference of Arrival used to located RFID tags is also disclosed.

Abstract: A method and apparatus to align data blocks in a data signal and a reference signal to increase cross-correlation between the data signal and the reference signal as compared to the unaligned data and reference signals and cancel interference in the data signal in the frequency-domain under changing conditions and in the presence of the data signal.

Abstract: A method of correlating a digital communications signal is described. In an example, a window is defined equal to a portion of an epoch of the digital communication signal. The digital communication signal is then correlated across the window. A determination is made as to whether a correlation peak results from the correlating. Timing parameters are then established for receiving additional digital communication signals in response to presence of the correlation peak.

Abstract: A method for transmitting a random access preamble to a base station includes generating the random access preamble from a Zadoff-Chu (ZC) sequence, wherein the random access preamble is defined by cyclic shift (Cv) of the ZC sequence; and transmitting the random access preamble to the base station.

Abstract: A synchronization method for impulse system ultra-wideband takes frame as basic unit for data transmission, each frame is divided into a preamble symbol part and a data part, wherein the preamble symbol part sends a known impulse sequence for channel estimation and synchronization; the data part takes the information to be transmitted; the preamble symbol part is divided into two parts of a positive and negative impulse sequence, which includes odd impulses with alternant positive and negative polarities, and a same direction impulse sequence, which is composed of impulses with same polarity and is the same as the polarity of the last impulse in the positive and negative impulse sequence. The method provides such advantages as high synchronization precision, small storage space, and capability of immediately finding out the synchronization position etc., and provides an important value for the development of the impulse system ultra-wideband wireless communication technique.

Abstract: Method and system for separating a plurality of users in a communication system including two transmitter antennas and N receiver antennas, said signals transmitted by said users containing symbols an, x( ) corresponding to the vector of the envelopes of the output signals of the 1 to N receiver antennas after a shaping filtering operation, characterized in that it uses a linear mean square filter extended over an observation vector {tilde over (x)}=[x(2n?1)T x(2n)T x(2n?1)H x(2n)H]T where x(2n?1) and x(2n) correspond to the (N×1) (N?1) observations at the symbol times 2n?1 and 2n.

Abstract: A method and a system for communication are presented. In one example embodiment, the method includes the step of receiving a first frame of a communication signal. The first frame includes a first plurality of constituents. One or more constituents of the first plurality of constituents of the first frame form a symbol of the first frame. The method includes the step obtaining a second frame. The second frame includes the first plurality of constituents. One or more constituents of the first plurality of constituents of the second frame form a symbol of the second frame. The symbols of the second frame are obtained by creating redundancies of the constituents of the first plurality of one or more symbols of the first frame. The first frame includes a second plurality of constituents. One or more constituents of the second plurality of the first frame form a preamble field of the first frame.

Abstract: Methods and apparatus for dynamically compensating for the effects of interference between multiple wireless communications apparatus. In one embodiment, the method comprises providing a first wireless communication apparatus operating in a first band and a second wireless communication apparatus operating in the same first band (or proximate to the first band and with a comparatively high transmitter power), where the second wireless communication apparatus operates according to a different communication protocol than the first wireless communication apparatus and further change in physical configuration with respect to one another. Based on the physical configuration, interference is compensated for between the first wireless communication apparatus and the second wireless communication apparatus “on the fly” by selecting and operating according to one of a plurality of operational protocols.

Abstract: To detect a special burst sequence, a cross correlation (C) is compared to a square root of an estimated noise variance (?) in conjunction with a threshold value (Th). In one aspect of the disclosure, the threshold value may include multiple threshold values. The multiple threshold values may be compared to an intensity or level of a special burst metric (C/?) to facilitate determination of the special burst sequence. For example, when a special burst metric C/? is greater than a second threshold value (Th2) it may be determined that a special burst sequence exists. However, when the special burst metric C/? is greater than a first threshold value (Th1), but less than the second threshold metric (Th2), it may be determined that detection of a special burst is unclear. In this case, a TFCI value may be used to confirm whether a special burst is detected.

Abstract: A wireless communication device according to the present invention includes a standard signal holding unit for holding a plurality of standard signals, a correlation value calculation unit for performing a correlation operation between a received signal and the plurality of standard signals, and a reference signal selection unit for determining a reference signal from among the plurality of standard signals on the basis of a correlation operation result obtained by the correlation value calculation unit. When a correlation value peak which provides a maximum value is not detected among a plurality of correlation values obtained by the correlation operation between the received signal and the plurality of standard signals, the reference signal selection unit repeats a predetermined number of times, a process of performing a correlation operation between a new standard signal which is generated so that a head of a data part is located at some midpoint in a predetermined symbol interval and the received signal.

Abstract: A receiver for receiving an RF signal transmitting a bit sequence representing a symbol is provided. The receiver includes an oscillator, a counter, at least one state machine and at least one correlator. The oscillator is configured to oscillate dependent on the received RF signal, wherein the oscillator signal is controlled to provide an oscillation signal based on the oscillation during a plurality of subsequent active periods. The counter is configured to provide a counter value describing threshold crossings of the oscillator signal for each of the active periods. The at least one state machine is connected to the counter and configured to output state values, each state value dependent on two subsequent counter values. The at least one correlator is configured to correlate the output state values with a predefined bit sequence and to output a value representing the symbol dependent on the correlation.

Abstract: A frequency offset estimation method for a multi-carrier communication system is provided. The method includes: transforming a representation of a reception signal from a time domain to a frequency domain, and generating a plurality of symbols; calculating a correlation of two symbols among the symbols, and obtaining a plurality of correlating complex numbers corresponding to a plurality of subcarriers; generating M number of candidate subcarrier position sets according to a subcarrier position set of a specific signal and M number of candidate frequency offsets; calculating M number of calculated values according to the correlating complex numbers corresponding to the M number of candidate subcarrier position sets; and determining a frequency offset according to the maximum calculated value among the M number of calculated values.

Abstract: Methods and apparatus are provided for detecting and decoding adaptive equalization training frames (having a frame marker comprised of a string of binary ones and binary zeroes). Training frames are detected by shifting the received data; inserting at least one binary value at one end of the shifted received data to generate a modified version of the received data; applying a logic function to the received data and the modified version of the received data that identifies when corresponding bit positions have different values; and detecting the frame marker when an output of the logic function has a first binary value in an approximate middle of a string of a second binary value. The training frames are decoded using a distance between the approximate center of the frame marker and a predefined binary value in an output of the logic function.

Abstract: A correlation magnitude signal is divided into a plurality of samples at a sequence of intervals over a symbol time, where the correlation signal corresponds to a magnitude of a correlation of a signal received at a receiver device with a known sequence. A sample with a highest magnitude value for the symbol time is selected from the plurality of samples. A symbol-synchronization signal that corresponds to an interval of the sequence of intervals containing the sample with the highest magnitude value is provided to a rake receiver system.

Abstract: Methods and apparatus for symbol timing recovery are provided. Both a coarse symbol timing recovery method and apparatus, and a fine symbol timing recovery method and apparatus are described which can be used jointly for symbol recovery, for example in phase shift keying receivers. The coarse method involves the use of differential correlations and finding the time difference in peak values of the correlation results. The fine method involves interpolation of a received digital signal, followed by filtering and timing error detection. The error detection signal is further filtered and used to control the interpolator. The methods provide for robust symbol timing synchronization.

Abstract: A receiver for receiving a layer-modulated signal includes: a base layer decoding unit configured to calculate a bit metric including code bit information of a base layer based on the reception signal and decode an information bit of the base layer; and at least one enhancement layer decoding unit configured to decode an information bit of an upper layer of a lower layer based on the decoding results of the lower layer, wherein the base layer decoding unit and the at least one enhancement layer decoding unit are sequentially connected according to the order of the corresponding layers.

Abstract: Aspects of a method and system for an improved cellular diversity receiver are described. Aspects of the system may include circuitry that enables generation of an initially decoded output bit sequence by a first frame process for a received bit sequence for a plurality of received multipath signals. The first frame process may utilize redundancy based decoding, which imposes at least one physical constraint during the decoding, which may be performed by a decoding algorithm.

Abstract: Systems, apparatus and methods for determining a cyclic shift diversity (CSD) mode are presented. Examples use two different autocorrelations to determine a current CSD mode. Specifically, a delay-based autocorrelation and a cyclic shift-based autocorrelation are each computed then compared to each other, for example, by taking a difference of the two autocorrelations. A multipath signal leads to similar autocorrelations, where as a signal with a CSD mode enabled leads to dissimilar autocorrelations. By examining the number of peaks in the delay-based autocorrelation or the autocorrelation difference, a current CSD mode may be determined.

Abstract: A system and method for reducing interference in a wireless communication system may include sending by a transmitter to a receiver a signal sequence s=(s1, s2, . . . , sL) of length L and information bit m, the signal sequence s having an interference signal sequence j=(j1, j2, . . . , jL). The system and method may also include identifying by the receiver an optimal lag ?° of the signal sequence s in relation to the interference signal sequence j, determining an estimate of the information bit m from the optimal lag ?° by the transmitter and calculating the signal to interference plus noise ratio by the receiver.

Abstract: A method for transmitting a random access preamble to a base station includes generating the random access preamble from a Zadoff-Chu (ZC) sequence having a length N, wherein the random access preamble is generated by considering a cyclic shift of the ZC sequence; and transmitting the random access preamble to the base station, wherein the cyclic shift is given by using a variable M corresponding to a Doppler shift of one subcarrier spacing, and wherein parameters associated with defining the cyclic shift are differently defined based on whether the variable M is less than ? of the length N.

Abstract: Provided is an identification signal analyzing apparatus and method for compensating power of a channel profile occurring at a conventional identification signal analyzing apparatus by using a power compensation. The identification signal analyzing apparatus includes: an identification signal generator for generating an identification signal identical to a known identification signal inserted by a transmission device; a partial correlator for calculating a correlation value between a received signal including the known identification signal inserted by the transmission device and the identification signal generated by the identification signal generator through a partial correlation; a power compensator for compensating power of the correlation value calculated by the partial correlator; and a channel profile extractor for extracting a channel profile from the correlation value compensated by the power compensator.

Abstract: Method of estimating a channel in a wireless communication system by obtaining a channel impulse response from a pilot signal included in a received signal; estimating a timing offset with a maximum peak power value for the channel impulse response; and performing a phase compensation using the estimated timing offset and estimating a channel which is applied with the compensated phase.

Abstract: A reception circuit is provided which can detect the beginning of data regardless of a preamble or a unique word contained or not in a received signal and regardless of coding systems for received signals. The reception circuit includes a correlation operation portion that performs a correlation operation to generate a correlation signal while sliding one symbol of reference signal in relation to a received signal. The reference signal goes to a high level during a first half symbol period and goes to a low level during a second half symbol period. The reception circuit further includes: a delay portion that outputs a delay signal by delaying the received signal for a half symbol period in relation to the received signal; and a data beginning timing detection portion that detects a beginning peak timing for the correlation signal as a beginning timing of data contained in the delay signal.

Abstract: When a changer changes a communication parameter based on a channel characteristic, a selector selects a switch data sequence corresponding to the changed communication parameter. A serial-parallel converter performs a serial-parallel conversion on a switch data sequence. An IFFT unit performs an IFFT. A transmitter synthesizes a calculation result from the IFFT unit to generate data symbol, and generates a transmission frame based on the data symbol. The transmitter then transmits the transmission frame to a second apparatus. A receiver receives a transmission frame from the second apparatus to generate data symbol. An FFT unit performs an FFT on the data symbol to generate a parallel signal. If a correlator determines that a notification of the change in the communication parameter has been correctly transmitted based on an autocorrelation analysis of the parallel signal, a communication apparatus starts communication using the changed communication parameter.

Abstract: A method includes receiving a signal, which carries data in a sequence of symbols that are modulated in accordance with a pulse shape and transmitted in accordance with a timing clock. The received signal is filtered with a matched filter whose response is matched to the pulse shape of the symbols, to produce a filtered signal. The timing clock is initially recovered from the received signal prior to filtering with the matched filter. Upon meeting a predefined condition, a switch is made to recover the timing clock from the filtered signal after filtering with the matched filter. The symbols are demodulated using the recovered timing clock, so as to reconstruct the data.

Abstract: A training symbol with two identical halves as well as a pilot-tone at a center frequency is used for both timing synchronization and carrier frequency offset estimation. A timing synchronization is achieved by finding a peak of a cross-correlation function of the two halves in the first symbol. A fraction part of the frequency offset FO is then calculated from a phase difference between the two halves of the first training symbol. Then, the received signal is compensated for the fraction part of FO, and, an integer part of the FO is obtained by counting the shifted positions of the pilot-tone peak in the frequency domain.

Abstract: A detection system includes a receiver configured to generate a receiver signal representative of detected electromagnetic energy, and an analog-to-digital converter (ADC) configured to generate a plurality of signal samples based on the receiver signal. The detection system also includes a detection module configured to identify a plurality of sample offsets for the signal samples, and execute a plurality of autocorrelation functions on the signal samples to provide an output of each of the autocorrelation functions, wherein each autocorrelation function is executed on at least a portion of the signal samples identified by a sample offset of the plurality of sample offsets. The detection module is also configured to compute a sum of the autocorrelation function outputs, normalize the sum of the autocorrelation function outputs, and determine whether a signal of interest is present within the electromagnetic energy based on the normalized sum.

Abstract: A circuit for detecting a predetermined symbol of a digital data stream includes a frequency shifter, a correlator, a filter and a decision unit. The frequency shifter performs inverse-frequency shifting upon a first data to generate a first frequency-shifted data. The correlator calculates correlation upon the first frequency-shifted data and a second data to generate a correlated data. The filter, coupled to the correlator, filters and the correlated data to generate a filtered correlated data according to a time-domain windowing length. The decision unit, coupled to the filter, determines the predetermined symbol from the digital data stream according to the filtered correlated data.

Abstract: In general, the subject matter described in this disclosure can be embodied in methods, systems, and program products for adapting data rate. The method includes receiving a data transmission at a data rate, identifying a first quantity of packets that were not adequately received, and using the first quantity to increase a packet loss level. A second quantity of improper bits in those packets that were adequately received at the data rate are identified, and the second quantity is used to increase a bit error level. As a result of having determined that the first value does not satisfy a first criterion for reducing the rate of the data transmission and that the second value does satisfy a second criterion for increasing the rate of the data transmission, an instruction is sent for causing the sending device to increase the rate of the data transmission.

Abstract: A method includes receiving a signal comprising a symbol-carrier matrix, the symbol-carrier matrix including a predetermined pattern of reference symbols, and determining at least one channel estimate ?i,k at at least one of the reference symbol positions of the reference symbols in the symbol-carrier matrix, wherein i=0,1,2, . . . is the carrier index and k=0,1,2, . . . is the symbol index of the symbol-carrier matrix. The method further includes determining a Doppler spread {circumflex over (?)}D on the basis of the at least one channel estimate ?i,k.

Abstract: A method and apparatus for providing uplink signal-to-noise ratio (SNR) estimation in a wireless communication system. A first signal is received over a first channel and a second signal is received over a second channel, where the second signal is received at a higher signal power level than said first signal. A signal-to-noise ratio (SNR) of the second signal is measured, and the SNR of the first signal is determined based at least in part upon the measured SNR of the second signal.

Abstract: A method for identifying a corrupted received signal that includes symbols is described. Each symbol may have a value of a Galois field associated therewith. The receiver may be configured to store a logarithm of normalized probability mass functions and corresponding Galois field values for each of the symbols. The normalized probability mass functions may be normalized with respect to a greatest probability mass function of a given symbol. The method may include comparing, for each symbol, a logarithm of normalized probability of an n-th best probability value with a respective threshold, counting a number of the logarithms that exceed the respective threshold and generating, for each symbol, a score corresponding to the number. The method may also include calculating a moving average of the scores, and comparing the moving average with an output threshold and flagging a just received symbol as corrupted based upon the comparison.

Abstract: A method of estimating frequency offset of a received signal in a terminal apparatus comprises a) determining a phase change between a first and a second reference symbol of the received signal, wherein the time distance t between the first and the second reference symbols is associated with an observation frequency f such that f=1/t. The method further comprises: b) determining a preliminary frequency offset ?f based on the determined phase change, wherein ?f forms a frequency offset hypothesis ?fh; and c) decoding at least a part of the received signal, with application of the frequency offset hypothesis ?fh, to a decoded signal. The method further comprises: d) determining whether the decoded signal is a successful decoding.

Abstract: The present invention relates to a method and apparatus for deconvolving a noisy measured signal obtained from a sensor device (100), said noisy measured signal (y(t)) being the sum of the convolution product (x(t)N(t)) of an input signal (x(t)) of the sensor device, representative of a feature of physical quantity, by a convolution kernel (N(t)) defined by the response function of the sensor device (100) and a noise which interfere with the measure. The method is characterized in that said method comprises an estimate computation step (400) in the course of which a minimal estimate (xmin(t)N(t)) of the convolution product of the input signal by the convolution kernel of the sensor device is computed in order that said minimal estimate stays below the noisy measured signal (y(t)) and has at least one point in common with the noisy measured signal (y(t)).

Abstract: The present invention relates to method of transmitting and receiving signals and a corresponding apparatus. One aspect of the present invention relates to an efficient layer 1 (L1) processing method for a transmitter and a receiver using data slices.

Abstract: A multimode communication device with a shared signal path programmable filter and a method for utilizing a shared signal path programmable filter in a multimode communication device. Various aspects of the present invention comprise a first module adapted to receive a first communication signal (e.g., corresponding to a first communication protocol) and a second module adapted to receive a second communication signal (e.g., corresponding to a second communication protocol). A shared filter, communicatively coupled to the first and second modules, may be adapted to filter the first and/or second communication signals in accordance with a plurality of selectable sets of filter response characteristics (e.g., associated with the first and second communication protocols). A filter control module may be adapted to select a set of filter response characteristics from a plurality of such sets and program the shared filter to filter a communication signal in accordance with the selected set.

Abstract: A radio receiver (100) includes a symbol recovery unit (108) the produces a raw symbol stream (112) and a recovered symbol stream (116). The recovered symbol stream is produced by applying symbol recovery parameters to the raw symbols. The symbol recovery parameters are updated (218) when the symbol recovery parameters used by the symbol recovery unit lack a requisite level of validity and there is a sufficient indication, based on successive instance of sync information using instance-specific recovery parameters, updated recovery parameters are valid.

Abstract: A method and apparatus for transmitting Channel State Information Reference Symbol (CSI-RS) and data with partial muting of the CSI-RS are proposed. The method includes determining a CSI-RS pattern to be used among CSI-RS pattern candidates, determining a muting pattern for muting some resource elements constituting CSI-RS pattern candidates except for the determined CSI-RS pattern, mapping data symbols and CSI-RS to resource elements in a resource grid with rate patching in consideration of the CSI-RS pattern and muting pattern, and transmitting the data symbols and CSI-RS to a terminal.

Abstract: The invention relates to a method for acquisition of a signal (2) emitted by a satellite, by a receiver in a satellite Positioning System using a multi-code correlation and a multi-frequency correlation, also comprising the step in which if the error induced at the output from a first frequency-augmented correlator (14) at each instant in an integration period is greater than the code space between code correlators (12), the summated results of the first frequency-augmented correlator (14) are transferred to the summated results of a second frequency-augmented correlator (14), the second frequency-augmented correlator (14) using the same frequency-shift as the first frequency-augmented correlator (14) and being associated with a second code correlator (12) that is shifted by the code space from the first code correlator (12) with which said first frequency-augmented correlator (14) is associated.

Abstract: A method for noise rise estimation in a wireless communication system comprises receiving (210) of radio signals. An interference whitening (212) is performed. A useful signal power for a first user after the interference whitening is determined (214) for a plurality of time instances. Furthermore, a first user noise floor compensation factor is derived (216) based on combining weights for the first user used in the interference whitening. A probability distribution for a compensated useful signal power for the first user is estimated (218). A conditional probability distribution of a noise floor measure is computed (220). A noise rise measure for the first user is then calculated (222) based at least on the compensated useful signal power for the first user and the conditional probability distribution of a noise floor measure.

Abstract: A method and system provide frequency offset compensation in a wireless communication device. A frequency offset compensation module (FOCM) correlates a received reference signal with sub-replica reference sequences to obtain a vector of matched filter output values associated with a time offset identified by a correlation time index value. The FOCM determines a correlation score vector using a combined energy associated with matched filter output values. The FOCM then determines a first phase difference based on matched filter output values corresponding to adjacent sub-replica sequences. The FOCM computes a second phase difference by linearly combining a selected first phase difference and at least one neighbor first phase difference having a second correlation time index value that differs from a first correlation time index value of the selected first phase difference. The FOCM uses the second phase difference to provide compensation for a frequency offset associated with received signals.

Abstract: In a signal detection apparatus, power detection section 101 detects power of an inputted received signal, and upon detection of power exceeding a power detection threshold, outputs a trigger to storage section 102. Storage section 102 stores a first received signal upon reception of the trigger and outputs the stored first received signal to multiplier 103 and newly stores a second received signal upon receipt of the next trigger. Multiplier 103 multiplies the second received signal by the first received signal, integrator 104 integrates the multiplication result from multiplier 103 during a predetermined duration to obtain a correlation value of the second and first received signals, and absolute value calculation section 105 calculates an absolute value of the correlation value from integrator 104. Determination section 106 determines the presence/absence of a detection-target signal based on the absolute value of the correlation value from absolute value calculation section 105.