Abstract: A method and apparatus for a base station including an antenna array calculates a direction of a weight vector of a transmission beam to maximize in-phase component power for a common channel signal in a transmission channel signal for transmission to a mobile station and to minimize a sum of quadrature-phase power component and interference power for other mobile stations inside and outside a cell due to a transmission channel signal for the mobile station.

Abstract: There is provided a transmit antenna array device with at least two antennas and a method thereof in which a transmission beam is appropriately formed based on a weight vector to be transmitted to a specific mobile station in a mobile communication system. For this purpose, a base station device has a reverse processor for processing a reverse signal received through the antenna array, a forward fading information extraction unit for extracting forward fading information from the received reverse signal, a beam formation controller for generating a weight vector for formation of a transmission beam using the forward fading information and the received reverse signal, and a forward processor having a transmission beam generator for generating a transmission beam for a transmission message based on the weight vector.

Abstract: A method for obtaining a gain function by using an array of antennae and a weighting of the signals received or to be transmitted by vectors of complex coefficients. The complex coefficients are referred to as weighing vectors, according to which, a reference gain function being given, the reference gain function is projected orthogonally onto the sub-space of a gain function. The sub-space of the gain function is generated by the weighting vectors of the space of the gain functions. The weighting vectors of the space of the gain functions are provided in advance with a norm, and a weighing vector generating the reference gain function thus projected is chosen as the optimum weighting vector.

Abstract: A method is provided for controlling the transmitting power in a mobile radio system a corresponding mobile radio system is also provided. A signal emitted from a transmitter is received by a receiver via a transmission channel of the mobile radio system. The transmitted signal is evaluated and a power control information item is generated based on the result of the evaluation. The power control information item is then transmitted back to the transmitter for adjusting the transmitting power. In order to determine the power control information item, the time response of the transmission channel is estimated and the transmitting power needed in the future is deduced therefrom.

Abstract: A system and method for narrowband pre-detection signal processing in passive coherent location applications is disclosed. A receiving subsystem receives a reference signal and a target signal from an uncontrolled transmitter. The target signal is reflected from a target. The passive coherent location system includes subprocessors that perform pre-detection operations on the reference and target signals. The functions include zero-doppler cancellation, quadrature demodulation, reference beam regeneration, coherent processing interval selection, power spectral density estimation, cross ambiguity function formation, and the like. Within these operations, the reference signal is filtered with respect to the target signal to form a first output reference signal. The first output reference signal is combined with the first target signal to form a first output target signal. The output target signal then is used for subsequent passive coherent location processing operations.

Abstract: A wireless communication device (e.g., a cellular telephone) includes one transceiver for voice or data communication and a global positioning system (GPS) receiver a signal for receiving a GPS signal from the GPS satellites. The GPS receiver does not receive the GPS signal when the transceiver is transmitting, so that the GPS signal receives may consist of multiple signal segments of various duration and various delays. A method is provided which combine correlations of these multiple signal segments cumulatively until a sufficiently signal-to-noise ratio is achieved to allow detection of the transmitted signal of one or more of the GPS satellites.

Abstract: A base station apparatus may include a plurality of antenna element groups that each have a plurality of antenna elements arranged in a vertical direction. A reception weight combining section generates a combined signal for each antenna element group by multiplying a signal received by each antenna element of the group with a weight and combining the weighted signals of the antenna element group. A selection section measures reception power of the combined signal for each antenna element group and selects an antenna element group based on the measured reception powers. A transmission weight combining section multiplies a transmit signal with a weight applied by the reception weight combining section to a signal received by an antenna element of the selected antenna element group, and a diversity transmission section transmits the transmit signal from the selected antenna element group.

Abstract: A process for locating radio sources by a two-channel high resolution radiogoniometer including a network of a specified number N of sensors. The process multiplexes the signals supplied by the N sensors on the inputs of only two receivers. Then, with the aid of a calculation device coupled to the outputs of the two receivers, the angles of arrival of the waves emitted by the sources are estimated on the basis of an estimation of the covariance matrix of the signals supplied by the two receivers.

Abstract: A searcher unit realizes stable operation of the a communication system and improves system capacity by improving path detection characteristics in the baseband processing unit of a receiving apparatus using an array antenna.

Abstract: A method and implementation of wireless communication are disclosed in which wireless signals are exchanged between at least one remote client and a directional antenna array associated with a wireless network, wherein the directional antenna array includes a plurality of antenna elements. A statistical matrix analysis is performed for each of the at least one client and the antenna array, in order to locate angles associated with directions of each client with respect to the antenna array. Values are determined for weighting factors for RF signals of each of the respective plurality of antenna elements, so as to create predetermined phase differences between the signals of the plurality of antenna elements. The predetermined phase differences are used to direct at least one null toward at least one source of interference, so as to avoid signal interference.

Abstract: The amount of calculations involved in the weight calculation is reduced in an adaptive array antenna CDMA receiver. A common correlation matrix is calculated by using the reception signals. Preferably, the inverse matrix of the common correlation matrix is also calculated. The common correlation matrix or the inverse matrix is used in common to the weight calculations for all the users or mobile stations. An inventive CDMA receiver includes a portion provided for each user. Each of the portions passes the reception signals through the respective matched filters to obtain respective despread signals; calculates a weight vector by using the common correlation matrix or the inverse matrix thereof; weighs the respective despread signals with the weight vector to obtain weighed despread signals; and combines the weighed despread signals into the transmission signal associated with each user.

Abstract: A signal detector is provided in which complex samples of a received signal are multiplied by data representative of a hypothesis, and the resulting product data is coherently integrated over a desired duration to provide correlation data representative of the level of correlation between the hypothesis and the signal. In one embodiment, the signal detector is part of a GPS receiver.

Abstract: A method (500) and a mobile station (160) for determining a code phase are described herein. The mobile station (160) may generate a first auto correlation function (ACF) associated with correlation samples over a range of code phases corresponding to a line-of-sight signal. The mobile station (160) may generate a second ACF within the mobile station based on measured correlation samples over a range of code phases. The mobile station (160) may compare the first ACF to the second ACF to generate a code phase offset between the first and second ACFs. The mobile station (160) may adjust the first ACF to match the second ACF.

Abstract: A method, used in locating a mobile transmitter, includes providing a set of cross-correlation values, wherein each cross-correlation value is associated with a corresponding TDOA and/or FDOA estimate and is produced by cross-correlating a reference signal with a cooperating signal. The reference signal comprises a copy of a signal transmitted by the mobile transmitter as received at a first antenna and the cooperating signal comprises a copy of the same signal as received at a second antenna. The method further includes determining a most likely range of TDOA and/or FDOA estimates, and then identifying an optimal cross-correlation value within a subset of cross-correlation values corresponding to the most likely range of TDOA and/or FDOA estimates. The TDOA and/or FDOA value corresponding to the optimal cross-correlation value is then employed in calculating the location of the mobile transmitter.

Abstract: A signal detector employs a coherent accumulation system that coherently combines the correlation results derived from segments of samples of a received signal. The segments may have non-uniform lengths and may have been obtained over different and non-overlapping time periods. The segments are obtained during sampling windows of arbitrary length and at arbitrary times, and the results of processing the segments are successively combined in a coherent manner (separate magnitude and phase accumulation) until a threshold signal-to-noise ratio (SNR) has been achieved. Coherent integration is enabled by introducing a carrier phase offset as well as a code phase offset, so that different segments are aligned in carrier phase as well as code phase. Although not limited to this application, in one implementation example, the signal detector is used in connection with and as part of a global positioning system (GPS) receiver.

Abstract: The present invention is directed to improving the accuracy with which a stationary array sensor provides cross directional measurements by providing an offset compensation to the stationary array sensor using the output of a scanning sensor associated with the manufacturing process. Exemplary embodiments correlate outputs from the stationary sensor array and the scanning array using a data reconciliation process. For example, a practical, real time data reconciliation of measurements from the scanning sensor and measurements from the stationary array sensor is achieved by computing offsets using a bank of Kalman filters to correlate outputs from the two sensors for each measurement zone, wherein each filter possesses a relatively simple computational structure. The Kalman filters can fuse the outputs from the stationary array sensor and the scanning sensor to track, and compensate, drift of the stationary array sensor.

Abstract: A blind anti-jammer pre-processor for detecting and alleviating the performance degradation due to strong jammers is disclosed. The anti-jammer pre-processor comprises a jammer detector (10) determining strong jammers based on the eigen-value spread associated with the received data correlation matrix, and an optimal combiner (12) producing nulls for suppressing the detected strong jammers and a main-beam for receiving Signals-of-interest (SOI). The present invention also discloses a GPS receiver comprising the anti-jammer pre-processor (32), a correlator (34), a phase compensator (36), and a hard decision detector (38). The outputs of the anti-jammer pre-processor (32) are sent to the correlator (34) to restore the bit stream. The predetermined 8-bit preambles in the first word associated with each subframe of GPS data are used to estimate the phase rotation introduced by the optimal combiner performed on the SOI.

Abstract: The invention relates to a method and to devices for determining in a positioning system the time of reception of a beacon signal which was received and tracked by a receiver. In order to enable a re-acquisition of the system time based on a noisy received signal, it is proposed that the method comprises as a first step reconstructing a beacon signal for an interval based on available information. Then, a cross-correlation is performed between the reconstructed signal and the received signal at different relative positions to each other. Next, the time of transmission of the received signal is determined based on information for the reconstructed signal and on the relative position resulting in the maximum correlation value. Finally, a time of reception of said received signal is determined as the sum of the determined time of transmission of the received signal and of a calculated time of flight of the received signal.

Abstract: A method for eliminating or reducing interference in a receiver, for example, interference in a satellite positioning system receiver caused by a co-located TDMA transmitter, including detecting (210) the presence of a jamming signal, generating a synchronous blanking signal (220), and reducing the jamming signal by blanking (230) the receiver with a blanking signal. In one embodiment, the jamming signal is detected in the receiver, for example, at a correlator output of a satellite positioning system receiver.

Abstract: In an adaptive array antenna receiving apparatus, signal to interference ratio (SIR) measuring units are provided in signal processing units, respectively. The SIR measuring units measure signal to interference ratios of existing fingers to supply the measured results for an antenna weight succession processing unit. The antenna weight succession processing unit selects one of the existing fingers on the basis of the measured results. The antenna weight succession processing unit extracts antenna weights from one of the signal processing units that corresponds to the selected finger. The antenna weight succession processing unit supplies the extracted antenna weights to a newly assigned finger or one of the existing fingers that path timing is greatly changed.

Abstract: A system and method for narrowband pre-detection signal processing in passive coherent location applications is disclosed. A receiving subsystem receives a reference signal and a target signal from an uncontrolled transmitter. The target signal is reflected from a target. The passive coherent location system includes subprocessors that perform pre-detection operations on the reference and target signals. The functions include zero-doppler cancellation, quadrature demodulation, reference beam regeneration, coherent processing interval selection, power spectral density estimation, cross ambiguity function formation, and the like. Within these operations, the reference signal is filtered with respect to the target signal to form a first output reference signal. The first output reference signal is combined with the first target signal to form a first output target signal. The output target signal then is used for subsequent passive coherent location processing operations.

Abstract: Methods and systems consistent with this invention receive a plurality of transmitted signals in a receiver having a plurality of receive elements, wherein each transmitted signal has a different spatial location. Such methods and systems receive the plurality of transmitted signals at the plurality of receive elements to form a plurality of receive element signals, form a combined signal derived from the plurality of receive element signals, and detect each of the plurality of transmitted signals from the combined signal by its different spatial location. To achieve this, methods and systems consistent with this invention generate a plurality of arbitrary phase modulation signals, and phase modulate each of the plurality of receive element signals with a different one of the phase modulation signals to form a plurality of phase modulated signals.

Abstract: When directional transmission using user multiplexing is performed in CDMA communication, the phase offset for setting antenna balance adaptively is determined. By this means, the antenna elements giving the maximum or minimum amplitude are dispersed reliably among individual users. As a result, the amplitude bias toward a specific antenna element can be decreased and the load on the transmission amplifier is further alleviated.

Abstract: An improved OFDM receiver is realized by employing a simplified delay function for the transmissions channel. The simplified delay function yields a simplified frequency-domain correlation that is applied to develop an Eigen matrix U that is used in developing estimates of the channels. Those channel estimates are used in the receiver to develop the output signals.

Abstract: A steerable antenna array (10) includes a plurality of antenna elements (12a-12f) which receive broad band signals and narrow band interfering signals which together form antenna signals. The antenna signals are combined with weighting signals by combining functions (16a-16f) to form a combined signal, which is filtered by a filter function (30) to filter the narrow band signals. The filtered signals are sent to a weight processor (50) which also receives the antenna signals as an input. The processor (50) generates the weighting signals so that interference from the narrow band signals is reduced.

Abstract: A system and method for detecting the presence of a transmitted waveform in a high noise environment. The system and method can detect and classify a modulated waveform without first demodulating the signal, and can detect and classify a waveform having a frequency offset without compensating for the frequency offset.

Abstract: An adaptive beamforming method for an antenna array is provided in which an array output is calculated based on a weight vector w, which is determined from an eigenvector corresponding to a maximum eigenvalue&lgr; of a generalized eigenvalue problem consisting of autocovariance matrixes Rxx and Ryy of received signal vectors y and x, respectively. The present invention dramatically decreases the total computation requirements by omitting complex matrix operations from the weight vector calculation, thereby making it possible to reduce the weight vector calculation time so as to form the beam pattern for the array antenna system in real time.

Abstract: The invention relates to a method of interference suppression in a radar system (10) and also to a system (10) operating according to the method. The system (10) incorporates a first antenna (40) and associated electronic circuits for emitting interrogating radar radiation towards a remote scene (S). Moreover, the system (10) also incorporates a second antenna (45) and associated electronic circuits for receiving interrogating radiation reflected from the scene (S) and generating correponding first and second processed signals. The first and second processed signals correspond to a broader main beam response of the antenna (45) and to a narrower main beam response thereof respectively. By mutually comparing the first and second processed signals, the system (10) is operable to identify those second processed signals affected by interference from the scene (S).

Abstract: The invention relates to a method for determining the correlation between a signal transmitted by a beacon and tracked by a receiver and a reconstructed signal expected to be received at the receiver, wherein the received signal and the reconstructed signal are shifted against each other. In order to provide a possibility of compensating residual sinusoidal modulations in the tracked signal, it is proposed that at each shifting position, the samples of the received and the reconstructed signal are multiplied and integrated separately in a plurality of sections. The results are multiplied with a shifted and complex conjugated version of itself. The products resulting in this second multiplication are integrated to receive a single final value for each shifting position. Finally, the maximum final value resulting for the different shifting positions is determined, the shifting position with the maximum value being considered as the shifting position with the maximum correlation.

Abstract: In a Wireless Location System, reception and demodulation of signals is often performed at many sites. A collision may occur, e.g., in a TDMA, AMPS, GSM, GPRS, EDGE, CDMA, CDMA 2000, or WCDMA system, when a signal of interest (a transmission from a mobile transmitter to be located) and an interfering signal are received at the same time and at the same site. In the event such a collision occurs, the interfering signal may have been demodulated by a receiver system, or SCS, at another site, and the demodulated data be known by the TLP. This interferer can be reconstructed and subtracted from the raw data representing the combined signal of interest and interferer at the site where the collision occurred. This technique can provide significant (e.g., approximately 10-15 dB) interference rejection, with little degradation to the signal of interest.

Abstract: A method for determining weight factors of antenna beams, the method comprising using at least one directional antenna beam implemented with an antenna array to establish a radio link, forming a radio cell with the antenna beam, dividing the radio cell into at least two different cells by dividing the antenna beam, selecting weight factors of antenna elements of the antenna array such that the antenna element specific sums of weight factors of a radio cell formed with the antenna array and corresponding weight factors of at least one, second radio cell formed with the same antenna array are at least substantially equal within predetermined limits in order to achieve a predetermined power balance between different antenna elements.

Abstract: A method and apparatus are provided that allows system calibration to be incorporated into a single function that also derives transmit parameters from receive parameters in a spatial diversity system. In one embodiment, the invention includes receiving signals at an antenna array from a plurality of different locations, deriving characterizations of the spatial parameters of the received signals, receiving measurements of a plurality of different signals transmitted from the antenna array to a plurality of different locations, deriving characterizations of the spatial parameters of the transmitted signals from the received measurements, and generating a transformation function for producing transmit spatial parameters based on measurements of received signals using the receive spatial parameter characterizations and the transmit spatial parameter characterizations.

Abstract: A system and method for detection and feature extraction in a passive coherent location system is disclosed. During a coherent processing interval, detection and feature extraction operations are performed to determine peak detections and target parameters for targets. The system forms an ambiguity surface that has ambiguity surface data or the coherent processing interval. Bins from a previous ambiguity surface are associated with the ambiguity surface data. New bins are identified for new target echoes within the ambiguity surface. Peak detections are formed from the bins. The peak detections correlate to the target echoes of the coherent processing interval. Target parameters for the targets are estimated from the peak detections.

Abstract: The invention concerns a passive radar receiver for a received orthogonal frequency division multiplex-type signal consisting of symbol frames each emitted on coded orthogonal carriers. After formatting the received signals into digital symbols (S1 S1), a filtering circuit (2) eliminates by subtraction or using a covariance matrix, in the symbol signal at least unwanted signals with null Doppler effect so as to apply a filtered signal (X′) including essentially signals backscattered by mobile targets to a Doppler-distance correlator (4).

Abstract: A method for processing signals from multiple receiving/transmitting elements that define an array antenna is disclosed. The method includes measuring uplink signals from the elements of the array antenna to form a directional downlink antenna response. A first covariance matrix between pairs of uplink signals is determined for desired signal components of the measured uplink signals. A second covariance matrix is determined for noise and interference components of the measured uplink signals. An antenna processing system computes adaptive weights based on the first covariance matrix, the second covariance matrix and a loading term to in effect form a directional downlink radiation pattern. The loading term represents a balance adjustment between a first performance rating of a particular coverage area versus second performance rating of the wireless communication system.

Abstract: A method of operating a radio-based communications system is described. Signals from a plurality of mobile stations can be received by a plurality of antennae (11) of a base station (10). Profiles of the received signals can be calculated by a plurality of path-profiler-units (12). Specified individual values can be selected from the calculated profiles by a path-selector-unit (14). A plurality of rake-finger-units (16) can be assigned to the arrival times of the selected individual values. A predetermined number of path-profiler-units (12) are provided which can be distributed with the aid of a path-profiler-manager (13) between the plurality of antennae (11) and the plurality of mobile stations.

Abstract: The invention relates to a beam forming network of an active antenna with deployable sub-arrays. According to the invention, the network receives information on deformation of the relative position of two panels. Establishing the coherence of the signals takes account of this information to restore the received signals. The invention also provides a spacecraft including the above kind of network and further provides a beam forming method. The invention also provides a system including a craft of the above kind and at least one beacon transmitter station.

Abstract: A device and method for determining the bearing of an incoming RF signal. The signal is received using a plurality of primary antenna element (5). Each antenna element feeds into a respective receiving channel (6) that downconverts the received RF signal to IF, preferably by mixing with a local oscillator signal. The local oscillator signal may be produced by diverting and combining portions of the received RF signals, by receiving the incoming RF signal using one or more auxiliary antennas (11), or by a tunable oscillator. Preferably, the local oscillator signal is conditioned and filtered before mixing. The IF signals are processed, either by analog or digital means, to infer the bearing of the incoming RF signal.

Abstract: The invention relates to a method for determining the correlation between a signal transmitted by a beacon and tracked by a receiver and a reconstructed signal expected to be received at the receiver, wherein the received signal and the reconstructed signal are shifted against each other. In order to provide a possibility of compensating residual sinusoidal modulations in the tracked signal, it is proposed that at each shifting position, the samples of the received and the reconstructed signal are multiplied and integrated separately in a plurality of sections. The results are multiplied with a shifted and complex conjugated version of itself. The products resulting in this second multiplication are integrated to receive a single final value for each shifting position. Finally, the maximum final value resulting for the different shifting positions is determined, the shifting position with the maximum value being considered as the shifting position with the maximum correlation.

Abstract: The invention concerns a method and a device for receiving a signal transmitted by a source with a plurality of antennas, in which a plurality of beam signals are obtained by weighting the signals received by the different antennas. The beam signals are correlated with the replica of a reference signal transmitted by the source and then combined by means of coefficients obtained from correlation results.

Abstract: Method and system for synthetic aperture radiometry not limited by the Van Cittert-Zernike theorem and the quasi-monochromatic assumption. A radiometer system (300) for imaging the emissions from a distribution of incoherent emission sources located within a target area comprising a first antenna (322) configured to receive a first signal (326) emitted primarily from a target area, and a second antenna (324) configured to receive a second signal (327) emitted primarily from the target area. The first and second antennas may be located at approximately the same distance from the target area (310) or at substantially different distances from the target area (310). The radiometer system (300) is configured to allow the second antenna (324) to move faster than the first antenna (322) with respect to the target area (310), with the second antenna (324) moving along a pre-determined trajectory corresponding to a synthetic aperture (430).

Abstract: In an adaptive antenna receiving apparatus, a plurality of correlations between adjacent antennas are detected for each path, a fixed beam unique to each path arrival direction of the desired wave is formed on the basis of a vector generated by averaging the detected correlations, and each path is received and combined, or a plurality of correlations between adjacent antennas are detected for each signal sequence despread with a plurality of chip timings, a fixed beam unique to the arrival direction of each signal sequence is formed on the basis of a vector generated by averaging the detected correlations, and a path timing is detected on the basis of a delay profile generated from an output of each signal sequence, or a plurality of correlations between adjacent antennas are detected for each signal sequence despread with a plurality of chip timings, a fixed beam unique to the arrival direction of each signal sequence is formed on the basis of a vector generated by averaging the detected correlations, a path

Abstract: The determination of the geographical location of a signal emitter by the coherent, time integrated measurement of received signal wavefront phase differences through a synthetic aperture and the reconstruction of the wavefront of the received signal. The location of an emitter is determined by coherently measuring the phase gradient of an emitted signal at measurement points across a measurement aperture. Each measured phase gradient is integrated to determine a vector having a direction from the measurement point to the signal emitter and an amplitude proportional to the received signal. A figure of merit is determined for each possible location of the signal emitter by integrating each vector with respect to a propagation path between the measurement point of the vector and the possible location of the signal emitter, and the location of the signal emitter is determined as the possible location of the signal emitter having the highest figure of merit.

Abstract: A method and apparatus for processing cochannel signals received at a sensor array in a cumulant-based signal processing and separation engine to obtain a desired set of output signals or parameters. For use in a signal recovery system, the output signals are recovered and separated versions of the originally transmitted cochannel signals. An important feature that distinguishes the cumulant-based system from other signal separation and recovery systems is that it generates an estimated generalized steering vector associated with each signal source, and representative of all received coherent signal components attributable to the source. This feature enables the invention to perform well in multipath conditions, by combining all coherent multipath components from the same source. In a receiver/transmitter system, the estimated generalized steering vectors associated with each source are used to generate transmit beamformer weight vectors that permit cochannel transmission to multiple user stations.

Abstract: A signal detector is provided in which complex samples of a received signal are multiplied by data representative of a hypothesis, and the resulting product data is coherently integrated over a desired duration to provide correlation data representative of the level of correlation between the hypothesis and the signal. In one embodiment, the signal detector is part of a GPS receiver.

Abstract: A complex signal correlator such as can be implemented in a correlation detector system affords a unique algorithm which estimates the codifference correlation between two complex signals based on the sum and difference of codifference estimates, each codifference estimate having equivalently associated therewith a dispersion estimate. Typical embodiments provide a receiving antenna and a receiver inclusive of the codifference correlator, wherein radio frequency waves are down converted and sampled, the sampled signals are correlated with a reference signal contained in a memory, and the resultant correlation signal is detected and transduced. The inventive correlator is based on an alpha-stable distribution and, in comparison with conventional alpha-stable distribution-based correlators, can more effectively operate in a realm wherein alpha is less than one.

Abstract: An adaptive antenna beamformer is presented, said beamformer including a first signal source 100 and a second signal source 102 and an ambient noise or other interfering signals source 106, which are exposed to an antenna array 104. The mixed signals 108 are provided to a blind source separation processor 110. The blind separation processor 110, in this case an Independent Component Analysis element, is comprised of a group of processes that are configured to separate mixtures of signals blindly. The blind separation processor 110, provides three outputs, a first signal output 112, a second signal output 114, and a third signal output 116. The signal outputs each correspond to their respective signal input.

Abstract: This invention discloses an interference cancellation method based on smart antenna, which can solve various interference in mobile communication systems such as multipath propagation, etc., while using smart antenna. The invention includes the steps of: with a beam forming matrix, beam forming the output signal of a receiver based on smart antenna, then getting a set of digital signals NRk(m); canceling other users main path signal included in NRk(m), then getting another set of digital signals NSk(m), which only includes needed signals and all interference signals; searching in digital signal NSk(m) and getting all multipath interference signals coming from other users; canceling other multipath interference signal in NSk(m); and superposing the user main path and each multipath signal in phase coincidence, then getting a digital signal with interference canceled.

Abstract: A signal detector is provided in which correlation analyses of multiple segments of a received signal from separate and distinct periods of time are combined to improve the detection capability of the signal detector. In one embodiment, the signal detector is part of a GPS receiver.

Abstract: An adaptive array antenna having a plurality of array antennas including a plurality of antenna elements which are spaced at first intervals at which a large first correlation is exhibited, the array antennas being spaced at second intervals at which a second correlation is negligible, where a diversity of effects are produced, such as fading compensation, eliminating by interference waves coming from the same direction, and augmenting the gain by main beam tracking, providing one or more calibration signal coupling parts and multi-beam synthesizing circuit are so as to remove individual variations in calibration signals and to perform highly reliable calibration.