Abstract: An approach is provided for correcting a reference clock of a GPS receiver. The approach involves determining one or more frequency offset values. The approach also involves determining one or more codes associated with one or more satellites. The approach further involves determining a second code associated with the one or more satellites. The approach additionally involves determining one or more delay values between the second code and the one or more first codes. The approach also involves determining one or more proportional values based on the one or more delay values and a determined correlation. The approach further involves determining one or more correlation peak values and determining one or more estimated frequency offset error values based on the one or more correlation peak values. The approach additionally involves causing a calibrated reference clock frequency value to change to a recalibrated reference clock frequency value based on the estimated frequency offset error values.

Abstract: An orientation and localization system is provided with spatial filtering capabilities that combines time polarization and space diversity to detect the direct lines of sight (LOS) and to deliver location and orientation estimates of mobile nodes.

Abstract: A base station for use in a mobile telephony network includes an antenna arrangement coupled to a transceiver arrangement for producing a plurality of beams. A method of testing the base station comprises detecting at the transceiver arrangement the signal strengths of a test signal received via the beams; comparing and/or correlating the said signal strengths detected at the transceiver arrangement; and using the results of the comparisons and/or correlations to determine the configuration of the antenna arrangement and transceiver arrangement and/or to detect faults. The comparison of average signal strengths can be used to detect cabling faults, and beam errors. The correlation of un-averaged signal strengths can be used to determine which beams have the same polarization. Beam pointing directions and the allocation of antennas to sectors can be determined by monitoring handovers of mobiles moving between cells. Frequencies may be allocated to sectors according to a frequency re-use scheme.

Abstract: Embodiments of a system and method for determining an angle-of-arrival (AOA) of signals received from a transmitting device are shown. Signals from the transmitting device are received through two or more pairs of spatially-diverse antennas. A non-inverted version of the signals received through a first antenna of a pair is injected into a first input of a surface-acoustic-wave (SAW) device. An inverted version of the signals received through a second antenna of the pair is injected into a second input of the SAW device. Signals present at tap outputs are processed to determine a time-difference-of-arrival (TDOA) between the signals received through each pair of antennas. The AOA may be calculated from the TDOAs determined from two or more pairs of antennas.

Abstract: Systems and methods that may be implemented to determine the location of an emitter of electromagnetic radiation having an unknown location, using a cooperative TDOA-based location methodology. The cooperative TDOA-based location methodology (e.g., such as TDOA/TDOA, TDOA/FDOA, etc.) may be implemented using at least one cooperative transmitter that transmits a cooperative electromagnetic (EM) signal from a known location that is received at multiple different EM sensing platforms that are also each of known location. The known geolocation of the cooperative transmitter may be used to resolve the signal arrival timing relationships between the different sensing platforms that is utilized to determine the location of another EM transmitter of unknown location.

Abstract: An apparatus and a method for controlling power in a wireless communication system are provided. The method includes receiving interference information comprising a resource usage rate, from at least one neighboring BS, calculating a throughput variance amount, which is expected if the serving BS changes power, experienced by the at least one neighboring BS, by using the interference information, calculating a throughput variance amount, which is expected if the serving BS changes power, of at least one Mobile Station (MS) having access to the serving BS, and controlling power for the at least one MS by using the throughput variance amount experienced by the at least one neighboring BS and the throughput variance amount of the at least one MS. The interference information represents a throughput variance amount generated in the at least one neighboring BS when the serving BS changes the power.

Abstract: A system and method for estimating the position of an object, such as a person, animal, or machine. The system includes first and second inertial measurement units, a first and second originator antennas, and a first and second transponder antennas. The system uses data from the inertial measurement units to estimate a position of the object. The system also calculates a range measurement between the first originator antenna and first transponder antenna. The system calculates a first CPD measurement between the second transponder antenna and the first originator antenna, and a second CPD measurement between the second originator antenna and the first transponder antenna. The range measurement and at least one CPD measurement are used to update a Kalman filter for estimating the position of the object. The system determines also updates the Kalman filter when one of the inertial measurement units is in a zero-velocity condition.

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: This disclosure provides a range side lobe removal device, which includes a pulse compressor for acquiring a reception signal from a radar antenna and generating a pulse-compressed signal by performing a pulse compression of the reception signal, a pseudorange side lobe generator for generating a pseudo signal of range side lobes of the pulse-compressed signal based on the reception signal, and a signal remover for removing a component corresponding to the pseudo signal from the pulse-compressed signal.

Abstract: A device is provided for use with a radio frequency identification (RFID) chip that receives and modulates a radio frequency (RF) signal. A substrate of the device includes a first short dipole antenna structure that backscatters a received RF signal to produce a first radiation pattern having nulls. A set of connection pads couple the RF signal from the antenna to a frontend transmitter circuit of the RFID chip. A second antenna structure backscatters the received RF signal by electromagnetic coupling to the first antenna structure and produces a second radiation pattern that complements the nulls in the first radiation pattern.

Abstract: Provided is an array signal processing device capable of, when a spatial averaging method is applied to array signal processing, reducing the number of antennas constituting an array antenna while making use of the spatial averaging method. In the array signal processing device (300), an array antenna (310) comprises four antennas (311-1 to 311-4) disposed at the four vertices of a parallelogram. Correlation calculation units (341-1, 2) calculate, based on a received signal, spatial correlation matrices for respective sub-array antenna (312-1) and sub-array antenna (312-2), the sub-array antenna (312-1) comprising the antennas (311-1, 3) disposed at the opposing two vertices and the antenna (311-2), the sub-array antenna (312-2) comprising the antennas (311-1, 3) and the antenna (311-4). An array rotation unit (342) converts a first spatial matrix of the calculated two spatial matrices to the complex conjugate thereof.

Abstract: A method for wirelessly transmitting geographic coordinate information and a system and apparatus implementing the method. The method may include obtaining a latitude coordinate and a longitude coordinate, correlating a first radio frequency to the latitude coordinate, correlating a second radio frequency to the longitude coordinate, transmitting a signal at the first radio frequency, and transmitting a signal at the second radio frequency.

Abstract: A method and apparatus for performing blind signal separation in an orthogonal frequency division multiplexing (OFDM) multiple-input multiple-output (MIMO) system are disclosed. A transmitter generates a plurality of spatial streams of data and transmits the spatial streams via a plurality of transmit antennas. A receiver receives the transmitted spatial data streams with a plurality of receive antennas and generates a plurality of receive data streams. The receiver performs a discrete Fourier transform (DFT) on each of the receive data streams to generate a plurality of frequency domain data streams. The receiver then performs a blind signal separation on the frequency domain data streams to recover spatial streams transmitted by the transmitter. The blind signal separation may be performed by using an independent component analysis (ICA) in the complex domain. The blind signal separation may be performed individually for each OFDM subcarrier.

Abstract: A method and apparatus for processing downlink communication and a corresponding assisting method and apparatus are provided. According to an embodiment, a method for assisting a base station in processing downlink communication in a user equipment includes: estimating a downlink channel between the base station and the user equipment; determining a spatial correlation matrix between the base station and the user equipment according to the result of estimating the downlink channel; determining at least one pre-coding vector among a plurality of pre-stored pre-coding vectors based upon the spatial correlation matrix; and notifying the base station about the determined at least one pre-coding vector and spatial correlation matrix. The downlink communication processing disclosed herein improves the performance of a system, improves the average throughput and the throughput of an edge user of the multi-user MIMO system and has a wider applicability scope than the original codebook and feedback mechanism.

Abstract: Systems and methods that may be implemented to determine the location of an emitter of electromagnetic radiation having an unknown location, using a cooperative TDOA-based location methodology. The cooperative TDOA-based location methodology (e.g., such as TDOA/TDOA, TDOA/FDOA, etc.) may be implemented using at least one cooperative transmitter that transmits a cooperative electromagnetic (EM) signal from a known location that is received at multiple different EM sensing platforms that are also each of known location. The known geolocation of the cooperative transmitter may be used to resolve the signal arrival timing relationships between the different sensing platforms that is utilized to determine the location of another EM transmitter of unknown location.

Abstract: A method for combining a plurality of individual location measurements, for use in a wireless location system, includes the following steps. A quality metric for a single location estimate is computed along with individual quality metrics and individual weightings for each individual location measurement. In addition, weighting operations incorporating a quality metric for a single location are performed, and the measurement weights are adjusted based on information about co-location groups; and a decision metric and common bias accounting for multiple reference measurements are computed.

Abstract: A receiver having an array antenna estimates arrival directions of multiple paths that arrive with an angular spread. Consequently, arrival direction estimation accuracy can be ensured without increasing throughput even if the power every path is low by estimating an average arrival direction of an entire set of multiple paths having the angular spread from a result of one angular spectrum by multiple correlation operation units that perform mutual correlation operations with pilot signals for baseband signals received by the array antenna, a path detection unit that detects multiple arrival path receiving timings by generating a delay profile based on output of each of the correlation operation units, a path correlation value synthesis unit that synthesizes a correlation operation value calculated in the multiple correlation operation units and an arrival direction estimation unit that collectively estimates multiple path arrival directions using output of the path correlation value synthesis unit.

Abstract: A method of realizing smart antenna based on software radio and system therefore in IMT-2000 CDMA system. Channel conditions are classified according to the features of wireless communication channel conditions, covariance matrix of array receiving signals is step-by-step dimension-reduced and decorrelated using special smoothing differential processing method, obtaining the structure related to the receiving signals by gradually converting correlated signal into independent signal sources and realizing conditions recognition, and respectively calculating receiving weights and transmitting weights using corresponding receiving adaptive beam forming algorithm and transmitting adaptive beam forming algorithm selected according to the result of channel condition classifying.

Abstract: Systems and methods of correlating potential transmitters with received radio signals is provided. Image data is provided including paths traveled by potential transmitter. Potential transmitters are identified within the image data along with path segments traveled by potential transmitters. A first and second transmitter calculate certain parameters of received signals assuming that signals originated along the path segments. The calculated signal parameters are then compared to measured signal parameter to determine whether a transmitter is associated with a particular path.

Abstract: In accordance with an example embodiment of the present invention, an apparatus, comprising a receiver configured to receive a first portion of a radio signal comprising a time redundant portion received at a first antenna and a second portion of the radio signal received at a second antenna, a correlator configured to determine a value of correlation between the first portion and the second portion and a processor configured to estimate direction of arrival of the radio signal based at least in part upon the value of correlation.

Abstract: In a wireless location system configured to use a baseline correlation method, an iterative approach to increasing location accuracy is disclosed. The quality of received signals is ordered from highest to lowest and used to calculate an initial location. The initial location is modified using the lower quality signals as constrained by the time and frequency deviation from the initial location and velocity estimate.

Abstract: A position location system, apparatus and method are disclosed. A coordinating device identifies a group of wireless devices for position location processing. The number of wireless devices in the group may vary according to the number of coordinates used to define a position within the system. The coordinating device obtains range measurements from which a distance between each pair of wireless devices in the group can be determined. In addition, the coordinating device acquires the known position of one wireless device in the group. Using this information, a position is determined for one or more devices in the group for which position data is not available. Optionally, the position data is validated by the coordinating device or another wireless device in the system and a final position is returned to the one or more wireless devices.

Abstract: Control circuitry is configured to control a sampler, in a sampling phase determination process, to sample a signal at a sampling period of T±T/n for outputting a sample set for each one of n phases of the sampled signal. Each one of n correlators has a first input configured to receive one of the sample sets, a second input configured to receive a PN signal, and an output which provides a correlation result from a correlation process between the sample set and the PN signal. The control circuitry is further configured to identify, from the correlation results, one of the phases associated with the optimal correlation result. The control circuitry is then configured to control the sampler, in a communication mode, to sample a received signal at a sampling period of T at the phase associated with the optimal correlation result.

Abstract: A system for estimating parameters of an incoming signal is provided. At least one antenna is coupled to at least one suitable receiver. The antenna(s) are spatially translated in an arbitrary trajectory. As the antenna(s) is being spatially translated, a data processing means samples the incoming signal at set intervals based on a clock signal provided by a system clock. By sampling the incoming signal at different times at different spatial locations on the arbitrary trajectory, the system acts as a synthetic antenna array. The different samplings of the incoming signal at different times and positions provide signal diversity gain as well as different readings which can be used to estimate and/or calculate various parameters of the incoming signal. The different samplings can be used to detect the incoming signal, estimate its angle of arrival, estimate its time of arrival, as well as other parameters.

Abstract: The invention relates to a device to be used in a wireless communication system with CSMA-based MAC, comprising transmitting circuitry for transmitting at least a first and a second RTS message and at least a first and a second data packet on a transmission medium, and a spatially selective antenna. It is further proposed that the device uses a distributed antenna that combines the antenna elements of several devices and that the device observes the transmissions of other devices, analyzes the observed transmissions for transmission patterns and adapts its own transmissions to the detected transmission patterns. The invention further relates to a system, a method and a computer program to be used in a wireless communication system.

Abstract: Calibration for a transmit chain of a device transmitting information to multiple devices over wireless links and receive chains of the multiple devices receiving information over one of the wireless links utilizing each of the estimates for different antennas of an access terminal as a separate estimate.

Abstract: Systems and methods of correlating potential transmitters with received radio signals is provided. Image data is provided including paths traveled by potential transmitter. Potential transmitters are identified within the image data along with path segments traveled by potential transmitters. A first and second transmitter calculate certain parameters of received signals assuming that signals originated along the path segments. The calculated signal parameters are then compared to measured signal parameter to determine whether a transmitter is associated with a particular path.

Abstract: The present invention relates to methods for adjusting a radiation beam pattern of an antenna arrangement providing coverage in an area. The antenna arrangement comprises an antenna having at least one array of antenna elements connected to a distribution network configured to generate the radiation beam pattern. The method comprises: arranging the antenna elements of said array in at least one column in an antenna plane in relation to a reference plane, each column comprising multiple antenna elements arranged in at least two sub-panels; arranging a motion sensor to the antenna arrangement, said motion sensor is configured to detect deviation of the antenna elements relative the reference plane; and adjusting a beam shape of the radiation beam pattern based on the detected deviation of the antenna to maintain coverage in the area by controlling the distribution network. The invention also relates to an antenna arrangement and base station.

Abstract: A system and method are provided for improving the performance of a beamforming antenna array in a wireless communications system. By observing a predetermined times of channel spatial signatures, one or more test spatial signatures are generated based on statistical analysis of the observed spatial signatures for predicting channel characteristics. A beamforming weight is derived based on the generated test spatial signatures for beamforming by an antenna subsystem of the wireless communication system.

Abstract: A bank of correlator modules is used to concurrently execute a series of sync channel searches in a system in which the available frequency spectrum is larger than a channel bandwidth and in which a sync channel bandwidth is more narrow than the channel bandwidth.

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: An electronic device (200,300) comprising an antenna arrangement with first and second antenna groups with first (122, 142) and a second (124, 144) radiation elements. The first and second radiation elements in each group have first and second respective polarizations and gain, and said groups also comprise a beam forming network (126, 146) connected to the radiation elements of the group and to an output selector (150). The beam forming network (126, 146) of each antenna group uses the radiation elements (122, 124; 142, 144) in the group to create a radiation pattern (127, 147) with a polarization which is a composite of the first and second polarizations of the elements in the group, so that a first (127) and a second (147) radiation pattern of composite polarization is created. The output selector (150) selects or combines signals received by the two antenna groups as its output.

Abstract: This system comprises: clusters of first nodes (CS1, CS2) for which orientation and localization can be required and at least a node (FN1, FN2, . . . ) called measuring node to determine the relative orientation and localization of said first nodes sharing with it direct lines of sight; Each node having radio station (11, 12, 13 . . . ) operating on the base of MIMO process involving various polarizations of the received and transmitted waves at their trans-mission and reception sides.

Abstract: In a wireless location system configured to use a baseline correlation method, an iterative approach to increasing location accuracy is disclosed. The quality of received signals is ordered from highest to lowest and used to calculate an initial location. The initial location is modified using the lower quality signals as constrained by the time and frequency deviation from the initial location and velocity estimate.

Abstract: A serving mobile location center (SMLC) receives a position request concerning a mobile-of-interest (MOI) operating in a discontinuous transmission (DTX) mode, and in response a wireless location system (WLS) is tasked to locate the MOI. A plurality of location measurement units (LMUs) are instructed to receive and digitize radio frequency (RF) energy. At the LMUs, a signal of interest is received and cross-correlated with a known training sequence to produce a received detection metric. The detection metric is weighted to favor the MOI even in the presence of interference from other mobile devices. The SMLC selects the LMU with the best weighted detection metric as a reference site and selects two or more LMUs with lesser weighted detection metrics above a threshold as co-operating sites. The received signal of interest is demodulated and demodulated data are distributed to the co-operating sites.

Abstract: Methods for estimating a distance between an originator and a transponder, methods for calculating a fine time adjustment in a radio, computer-readable storage media containing instructions to configure a processor to perform such methods, originators used in a system for estimating a distance to a transponder, and transponders used in a system for estimating a distance to an originator. The methods utilize fine time adjustments to achieve sub-clock cycle time resolution. The methods may utilize offset master clocks. The methods may utilize a round-trip full-duplex configuration or a round-trip half-duplex configuration. The method produces accurate estimates of the distance between two radios.

Abstract: Systems and methods of correlating potential transmitters with received radio signals is provided. Image data is provided including paths traveled by potential transmitter. Potential transmitters are identified within the image data along with path segments traveled by potential transmitters. A first and second transmitter calculate certain parameters of received signals assuming that signals originated along the path segments. The calculated signal parameters are then compared to measured signal parameter to determine whether a transmitter is associated with a particular path.

Abstract: A positioning method includes: executing a first correlation accumulation process on a received signal, a positioning signal spread-modulated with a spread code, and a replica code of the spread code while shifting a phase of the replica code in a first phase search range, setting a second phase search range narrower than the first range based on an accumulated correlation value at a first timing in the first correlation accumulation process, executing a second correlation accumulation process on the received signal and the replica code while shifting the phase of the replica code in the second phase search range, determining appropriateness of the second phase search range based on the accumulated correlation value at the first timing and an accumulated correlation value at a second timing in the first correlation accumulation process, and positioning using a result of the second correlation accumulation process, if the second phase search range is determined appropriate.

Abstract: A motion compensation method and system is included in a radar antenna system mounted on a moving platform which is subject to pitch, yaw and roll. The radar antenna system includes a main array antenna, and an auxiliary antenna. The auxiliary channel associated with the auxiliary antenna utilizes roll, pitch and yaw angle motion compensations as its auxiliary antenna always steers a horizontal fan shape beam at the horizon to blank any surface (land or sea) based EM interferences. Such motion compensations are provided by a ship motion compensator component and process included within the antenna system. The ship motion compensator component in response to platform motion signals indicative of changes in platform motion angles generates new sets of values using an initial set of weighting coefficient values as a function of such angle motion changes.

Abstract: An active antenna array is arranged to activate subsets of switchable elements causing the antenna to form a first beam having a first beam pattern, and later to form a second beam having a second beam pattern of substantially identical far field radiation pattern to the first beam pattern but with different origins. A receiver receives radiation reflected from a target back to the antenna when the antenna is configured with the first beam pattern and then when configured with the second beam pattern, and compares the phase of the radiation received at the receiver when the antenna is configured with the first beam pattern with the phase of the radiation received at the receiver when the antenna is configured with the second beam pattern to provide a phase difference signal. A target locating means determines the angular location of the target from the phase difference signal.

Abstract: The location of a receiver is determined by receiving respective ranging signals from each of a plurality of transmitters at known locations. The ranging signals are cross-correlated with respective model signals to provide respective cross-correlation functions. For cross correlation functions that are determined to include multipath noise, the multipath noise is estimated and removed. Respective delays of the cross-correlation functions are estimated and the location of the receiver is inferred from the delays.

Abstract: A method of providing signal coverage in a wireless network includes establishing communications between a first wireless access unit and a second wireless access unit. In response to a communications device, the first wireless access unit weighting factor is modified to provide the communications device with optimal signal coverage. The first radiation weighting factor is transmitted to the second wireless access unit, which modifies its own weighting factor to provide the communications device with sufficient signal coverage.

Abstract: The angle of arrival is estimated for a received signal received by an array of commutated antenna elements, wherein there is a temporal boundary at the instant of commutation between antenna elements. Samples of the signal received by the elements of the array are preprocessed to construct maximum-likelihood-estimates of the received signal for points in time that are immediately adjacent the temporal boundaries and thereby provide a preprocessed signal. A maximum-likelihood-estimation of the angle of arrival of the received signal is made for the array of commutated antenna elements by processing the preprocessed signal.

Abstract: A system and method are provided for improving the performance of a beamforming antenna array in a wireless communications system. A predetermined number of spatial signatures are observed for a communications channel between a base station and a mobile terminal during a predetermined time period. One or more test spatial signatures are generated based on statistical analysis of the observed predetermined number of spatial signatures. A beamforming weight is derived based on the generated test spatial signatures for beamforming by an antenna subsystem of the base station.

Abstract: Provided is an array signal processing device capable of, when a spatial averaging method is applied to array signal processing, reducing the number of antennas constituting an array antenna while making use of the spatial averaging method. In the array signal processing device (300), an array antenna (310) comprises four antennas (311-1 to 311-4) disposed at the four vertices of a parallelogram. Correlation calculation units (341-1, 2) calculate, based on a received signal, spatial correlation matrices for respective sub-array antenna (312-1) and sub-array antenna (312-2), the sub-array antenna (312-1) comprising the antennas (311-1, 3) disposed at the opposing two vertices and the antenna (311-2), the sub-array antenna (312-2) comprising the antennas (311-1, 3) and the antenna (311-4). An array rotation unit (342) converts a first spatial matrix of the calculated two spatial matrices to the complex conjugate thereof.

Abstract: An adaptive array control device is described. The adaptive array control device includes a first array processing section and a second array processing section in which phase responses are almost opposite with respect to a target signal and a signal incoming from another direction. The adaptive array control device further includes a control signal generation section, and a control section. The control signal generation section calculates a control signal using output signals of the first array processing section and the second array processing section. The control section controls speed and accuracy of parameter adjustment in adaptive array processing using the control signal. An adaptive array controlling method, and a computer readable recording medium storing an adaptive array controlling program are also described.

Abstract: Embodiments of a system and method for determining an angle-of-arrival (AOA) of signals received from a transmitting device are shown. Signals from the transmitting device are received through two or more pairs of spatially-diverse antennas. A non-inverted version of the signals received through a first antenna of a pair is injected into a first input of a surface-acoustic-wave (SAW) device. An inverted version of the signals received through a second antenna of the pair is injected into a second input of the SAW device. Signals present at tap outputs are processed to determine a time-difference-of-arrival (TDOA) between the signals received through each pair of antennas. The AOA may be calculated from the TDOAs determined from two or more pairs of antennas.

Abstract: A coherent integration section synthesizes an IF signal stored in a memory and a C/A code replica generated by a code generation section using a mixer to calculate a correlation value, and integrates the correlation value using an integration section. An integration count monitoring section counts the integration count of the integration section. When a saturation control section has detected saturation of integration of the correlation values, the integration count monitoring section causes the integration section to suspend integration when the integration count is equal to or less than a reference count, and allows the integration section to continue integration when the integration count has exceeded the reference count.

Abstract: A secure communication topology can be used for communications between a locator and one or more transponders to determine the location of the transponders. An example system may include a locator that is configured to transmit an interrogation signal that is encoded for receipt by one or more of the transponders. When a transponder receives and correlates the interrogation signal with an internally stored reference sequence, the transponder can transmit one or more reply transmissions at precisely determined time delay intervals. The time delay intervals are secretly known by both the locator and the transponder. The reply transmissions can each correspond to previously sampled noise signals that are also secretly known by both the transponder and the locator.

Abstract: A technique for determination of the signal subspace dimension by using the ratios between the squared singular values of the processed data matrix and of its sum with an auxiliary matrix composed of random entries from a normal distribution. The disclosed noise addition technique (NAT) is computationally effective and thoroughly tuned for use in direction of arrival estimation and in exponentially damped sinusoids modeling, causes very few false alarms, operates accurately within or below the SNR limits attained by others techniques and downwards determines a steadily decreasing to zero dimension of the signal subspace.