Class / Patent application number | Description | Number of patent applications / Date published |
342387000 | Iso-chronic type | 72 |
20080231511 | Beacon-Assisted Precision Location of Untethered Client in Packet Networks - A novel beacon-based position location technique for efficient location discovery of untethered clients in packet networks is disclosed. The position location technique utilizes the time-difference-of-arrival (“TDOA”) of a first signal transmitted by a beacon of known location and a second signal transmitted by an untethered client. The TDOA of these two signals is measured locally by at least three non-collinear signal receivers. For each of the receivers, the TDOA is used to calculate a perceived distance to the client. A circle is then calculated for each receiver, centered on the receiver and having a radius equal to the perceived distance. At least two lines defined by points of intersection of the calculated circles are then calculated. The point of intersection of the lines represents the location of the client. To facilitate operation, the signal receivers may be arranged on vertices which define a convex polygon as viewed from above. The location system requires no time (time-of-day) synchronization of the signal receivers, and only the coarse frequency synchronization, on the order of, tens of parts-per-million (ppm). The technique even works for the case where the signal receivers are run asynchronously, provided the frequency accuracies of the signal receivers are on the order of about 50ppm or better. The technique introduces no communication overhead for the beacon, client and signal receivers. Further, the computation overhead at the signal receivers is relatively low because the location detection algorithm involves only simple algebraic operations over scalar values. | 09-25-2008 |
20080252525 | Determining a Geolocation Solution of an Emitter on Earth Based on Weighted Least-Squares Estimation - Embodiments provide systems and methods for determining the geolocation of an emitter on earth based on weighted least-squares estimation based on two TDOA and two FDOA measurements, none of which need to be acquired at the same time. The four TDOA and FDOA measurements and the errors in each of the measurements are determined. Weights for the errors in the TDOA and FDOA measurements are determined, and the weights are applied in a weighted errors function. The weights account for the errors in the measurements and the errors in the satellite positions and velocities, and are dependent on the localization geometry. The weighted errors function is minimized to determine the location estimate of the unknown emitter. | 10-16-2008 |
20080258973 | RANGING SIGNALS METHODS AND SYSTEMS - A system and method for estimating the range between two devices performs two or more ranging estimates with subsequent estimates performed using a clock that is offset in phase with respect to a prior estimate. The subsequent estimate allows estimate uncertainties due to a finite clock resolution to be reduced and can yield a range estimate with a higher degree of confidence. In one embodiment, these additional ranging estimates are performed at n/N (for n=1, . . . N−1, with N>1 and a positive integer) clock-period offset introduced in the device. The clock-period offset can be implemented using a number of approaches, and the effect of clock drift in the devices due to relative clock-frequency offset can also be determined. To eliminate the bias due to clock-frequency offset, a system and method to estimate the clock-frequency offset is also presented. | 10-23-2008 |
20080291089 | Apparatus and Method for Computing Location of a Moving Beacon Using Time Difference of Arrival and Multi-Frequencies - Provided is an apparatus and method for computing the location of a radio beacon by using Time Difference Of Arrival (TDOA) and multiple frequencies. The apparatus and method of the present invention compute the location of a radio beacon without limitation in distance by using multiple frequencies and time difference of arrival to resolve the problem of phase ambiguity. A radio beacon location computing system includes a plurality of base stations configured to receive signals of multiple frequencies transmitted from the radio beacon, and detect and output phase differences and arrival time; and a location computing server configured to receive the phase differences and the arrival time outputted from the respective base stations, acquire calculation distances based on the phase differences, remove phase ambiguity from the calculation distances based on the arrival time, and compute the location of the radio beacon. | 11-27-2008 |
20080291090 | Method For Estimating Distance Between Transmitter and Receiver, and Transmitter and Receiver Implementing Same - A method for estimating the distance between a transmitter and at least one receiver. The transmitter has radio transmission circuitry, at least part of which is operable in a first operation mode for transmitting a first signal type within a first bandwidth and in a second operation mode for transmitting a second signal type including at least a ranging component which occupies a second bandwidth which encompasses and exceeds the first bandwidth. The method includes the steps of: (i) operating part of the radio transmission circuitry in a second operation mode, (ii) transmitting a signal of a second signal type, (iii) receiving a signal on one receiver and (iv) estimating the distance between the transmitter and a receiver from the ranging component in each received signal. A suitable transmitter and receiver for implementing the method are described. | 11-27-2008 |
20090027270 | Apparatus and Method for Determining Receiver Performance in a Multilateration System - In a multilateration system receivers are grouped into two groups. The first group is used to determine a position of a signal source, for example, an aircraft equipped with a SAR transponder. From the determined position, predicted time of arrival values are produced for the second group receivers. These are compared with the actual time of arrival values for the signals arriving at the second group receivers. A difference is determined and then the variation of that difference is determined as the aircraft travels in its track. The groupings are then varied and further variations determined. When the minimum variation is determined an alert is given that the second group has a receiver which is operating with a larger than desirable group time delay. | 01-29-2009 |
20090027271 | APPARATUS AND METHOD FOR DETERMINING THE POSITION OF AN OBJECT IN 3-DIMENSIONAL SPACE - An apparatus and method is disclosed for determining the position of a user interface mouse using time of arrival measurements. A transmitter transmits a signal to an array of receivers that are spatially separated from one another. The time difference of arrival for is found for each receiver relative to a predetermined reference receiver. Using the time difference of arrival (TDOA) of each receiver, the location in 3-dimensional space of each receiver, and the speed of sound the position of the transmitter in 3-dimensional space relative to the reference receiver may be found. | 01-29-2009 |
20090058729 | Measuring Positions - Techniques, systems and computer readable medium are disclosed for measuring a position of an object device. A position measuring apparatus includes a receiving unit designed to receive a signal transmitted from an object device for position measurement. The position measuring apparatus also includes a position computing unit designed to compute a position of the object device by applying Angle Of Arrival (AOA) and Time Of Arrival (TOA) techniques using the received signal. The position measuring apparatus also includes a medium channel estimating unit designed to estimate a channel of a medium, through which the received signal penetrates on a transmission path, using the received signal. The position measuring apparatus also includes a position correcting unit configured to compute a delay time caused by the received signal penetrating the medium using the estimated medium channel and correcting the position of the object device computed by the position computing unit using the delay time. | 03-05-2009 |
20090079633 | CALIBRATION OF A LOCATION SYSTEM - A location system comprising a plurality of base units for enabling the locating of a device by means of one or more location signals communicated between the device and the base units and signal processing equipment for: i. determining the location of the device in dependence on the manner in which the location signal(s) is/are received and ii. deriving calibration data for calibrating the system in dependence on the manner in which the location signal(s) is/are received. | 03-26-2009 |
20090109094 | SYSTEM AND METHOD FOR PERFORMING TIME DIFFERENCE OF ARRIVAL LOCATION WITHOUT REQUIRING A COMMON TIME BASE OR CLOCK CALIBRATION - A method for performing Time Difference Of Arrival (TDOA) that eliminates the need for a common time base or clock calibration and a system for implementing the method. The method relies on a packet transmitted from a reference wireless device (first wireless device) with a known propagation delay between the first wireless device and a second device, which serves as a common reference point for all TDOA estimates. When a packet is received from a wireless device by the first wireless device and the second wireless device, the time difference of arrival is computed based on when the signal was received by the first device and the second device, using the known propagation delay to compensate for differences in clocks and frequencies between the first wireless device and the second wireless device. | 04-30-2009 |
20090115661 | POSITIONAL INFORMATION PROVIDING SYSTEM, POSITIONAL INFORMATION PROVIDING APPARATUS AND TRANSMITTER - Positional information is provided at a place out of reach of radio wave. The process executed by a positional information providing apparatus includes the steps of: obtaining a received positioning signal (S | 05-07-2009 |
20090160710 | Method and apparatus for estimating location to support location based service of terminal in mobile communication system - A method and an apparatus for estimating a location to support a location based service of a terminal in a mobile communication system are provided. The method includes receiving first reference signals from three base stations, calculating TDOAs, and solving a first equation using the TDOAs based on the first reference signals; when a solution of determining a location of a terminal based on the first equation is real or imaginary values, receiving second reference signals from the three base stations, calculating TDOAs, and solving a second equation using the TDOAs based on the second reference signals; and when a solution of determining the location of the terminal based on the second equation is real or imaginary values, determining the location of the terminal based on a relation between the first equation and the second equation. | 06-25-2009 |
20090195456 | Single Input Multiple Output (SIMO) Ranging and Positioning Systems - A method estimates a delay in a time of arrival (TOA) of a transmitted signal by receiving the transmitted signal at multiple antennas via corresponding channels. Each received signal is correlated with the transmitted signal to obtain estimated channel coefficients and an estimated TOA. A variance of noise is also obtained for each received signal. A weight is determined for each received signal by dividing the channel coefficients by the variance of the noise. The weights are summed, and each weight is multiplied by the estimated TOA to produce a weighted estimated TOA, which are also summed. The summed weighted estimated TOA are divided by the summed weights to determine a final TOA estimate with respect to the transmitted signal. | 08-06-2009 |
20090213008 | Multiple RF receiver and locating method using the same - A multiple RF receiver and locating method using the same have developed. The multiple RF receiver includes: a clock generator for generating a clock according to multiple RF receiving modules included in a multiple RF receiving unit; a phase distributor for dividing the clock into clocks having different phases, and providing the clocks to the multiple RF receiving unit as clock sources; the multiple RF receiving unit for generating SFD (Start of Frame Delimiter) signals by using the phases of the clocks provided as the clock sources; and a time measuring unit for measuring the SFD signals for use as data for location measurement. | 08-27-2009 |
20090267837 | Arrival-Time Locked Loop - This patent disclosure presents circuits, systems and methods to produce a stable signal from a reference signal source. These new inventions are far better than the current technologies to provide a stable signal with less phase noises. This new invention also provides a new approach to analyze the feedback control loop without using the traditional feedback control theory. | 10-29-2009 |
20090273518 | Associating a Universal Time with Received Signal - A method of associating a universal time with time of arrival information of an identified component of a signal at a terminal of a radio positioning system is disclosed. In the method a marker signal with an associated universal time tag is obtained from a timing device (or the marker signal is obtained from an independent oscillator and a universal time tag assigned to the marker signal), and the time or phase relationship between the marker signal (or between the time of arrival information of said identified component respectively) and the oscillator is measured. The time of arrival information of said identified component relative to the oscillator is determined and the universal time corresponding to the time of arrival information of said identified component is calculated from said universal time tag and said measured time or phase relationship, before the calculated universal time is associated with said time of arrival information. | 11-05-2009 |
20090273519 | Multilateration Apparatus - In a multilateration apparatus a correlator is provided with a time of arrival correlation window which is set to cater for the path lengths that may be experienced before a signal from an object to be located is received by receivers in the system. This may be on the basis of the largest possible path length in the system or on a receiver by receiver basis. | 11-05-2009 |
20090289851 | REFERENCE BEACON METHODS AND APPARATUS FOR TDOA/FDOA GEOLOCATION - A method and apparatus for estimating bias errors in a time-difference-of-arrival/frequency-difference-of-arrival (TDOA/FDOA) geolocation system using a reference signal transmitter in which position and/or motion information of the reference signal transmitter is encoded into the reference signal. The motion information may include the velocity and/or acceleration of the reference signal transmitter. The reference signal is received by multiple collection platforms operating in conjunction with a geolocation system and a reference correction processing system. The reference correction processing system receives, via the multiple collection platforms, the position and/or motion information, which is immediately and unambiguously associated with specific reference signal transmissions. The geolocation system estimates the position and/or velocity of the reference signal transmitter using conventional TDOA/FDOA techniques. The estimated position and/or velocity of the reference signal transmitter is compared to the information contained in the reference signal to estimate bias errors. | 11-26-2009 |
20090295638 | USE OF A MEASUREMENT SIGNAL EVALUATION MEANS OF A POSITION MEASURING DEVICE TO DETERMINE THE TIME DIFFERENCE BETWEEN A FIRST EVENT AND A SECOND EVENT - A position measurement system is provided to determine a time difference between a first event and a second event. Position values are hereby determined from an individual periodic signal or from a plurality of periodic signals, wherein a first position value is determined using a measurement signal evaluation means when a first event occurs, and a second position value is determined using the measurement signal evaluation means when the second event occurs. The time difference is determined from the first and second position values. As a result, the time difference can be measured between two events with a high temporal resolution, with a reduction of electromagnetic interference caused by the time measurement. | 12-03-2009 |
20090295639 | AUTONOMOUS ULTRASONIC INDOOR LOCATION SYSTEM, APPARATUS AND METHOD - An autonomous ultrasonic indoor location system includes a location beacon transmitting apparatus and a location beacon receiving apparatus. The location beacon transmitting apparatus is configured to sequentially transmit US signals at a predetermined time interval upon transmission of a signal containing synchronization information. The location beacon receiving apparatus is configured to synchronize with the location transmitting apparatus when synchronization information is detected, determine transmission order of the received US signals based on the obtained synchronization timing, infer transmission timings of the respective US signals based on the determined transmission order, calculate TOA information corresponding to each of the received US signal from the transmission timings and reception timings of the respective US signals, and determine location of the location beacon receiving apparatus on basis of the positions of the US transmitters in the transmitting apparatus and the calculated TOA information sequence. | 12-03-2009 |
20090303130 | Mobile system and method for position estimation - The present invention provides a method by which the position of a wireless emitter can be estimated by using a minimum of two wireless transceiver devices. The invention relies on physically moving the wireless transceiver devices to new position locations in order to obtain multiple time difference of arrival measurements. The time difference of arrival measurements can then be combined to derive estimates for the position of the emitter. At least one of the two wireless transceiver devices needs to be mobile with the other one fixed. Using this invention, any proportion of mobile and fixed transceiver devices can be used to derive the position of a wireless emitter. The wireless emitter to be located is not assumed to provide any information about itself to the wireless transceivers used for estimating its position location. The method is referred here as a Mobile-TDOA method or M-TDOA. The method is very general, very flexible and can be very inexpensive due to the minimum amount of hardware resources required. | 12-10-2009 |
20090322615 | METHOD AND DEVICE FOR TRAVEL TIME-BASED LOCATION IDENTIFICATION WITH THE AID OF A TRIGGERED OR SELF-TRIGGERING REFERENCE SIGNAL - A method for the detection of an object by the TDOA principle is provided. The object transmits a signal, which is received by a plurality of stations having known positions. The stations' clocks can have different unknown time delays in relation to each other. An additional stationary reference station having a known position relative to the stations and transmitting a signal that is received by the stations is provided. An unknown transmission delay can be generated between the emission of the signal from the object and the emission of the signal from the reference station. For each station the difference in travel time between receipt of the signal from the object and the signal from the reference station and the difference of the travel time differences between the stations are determined. Mathematical algorithms for determining the location are performed. | 12-31-2009 |
20100026576 | METHOD FOR MEASURING THE TIME OF ARRIVAL OF RADIO SIGNALS - A method for measuring the time of arrival of radio signals within a network comprises receiving the received signals including at least a first pseudorandom code and a second pseudorandom code from at least one other node; identifying a frequency difference between the node and the other node using a phase difference between each of a maximum value of a cross-correlation provided by the first pseudorandom code and the second pseudorandom code; applying the frequency difference to the reception of the received signal; and calculating the time of arrival of the received signal comprising a time, measured with a local clock, when the cross-correlation has achieved the maximum value. | 02-04-2010 |
20100026577 | RADIO-BASED POSITION LOCATION SYSTEMS, ANTENNA CONFIGURATIONS, AND METHODS FOR DETERMINING ANTENNA CONFIGURATIONS - A radio-based position location system for determining a relative position of a first object with respect to a second object may include a first radio operatively associated with the first object. A first directional antenna having at least a high gain region is mounted to the second object so that the high gain region is directed generally outwardly from the second object and defines a first detection zone. A second directional antenna having at least a high gain region is also mounted to the second object and is oriented so that the high gain region is also directed generally outwardly and defines a second detection zone. A second radio connected to the first and second directional antennas exchanges radio signals with at least the first radio to determine the relative position of the first object with respect to the second object at least in part by determining a time-of-flight of a radio signal. The radio signals are primarily exchanged via the first directional antenna when the first object is in the first detection zone, whereas the radio signals are primarily exchanged via the second directional antenna when the first object is in the second detection zone. | 02-04-2010 |
20100033379 | REFERENCE BEACON IDENTIFICATION USING TRANSMISSION SEQUENCE CHARACTERISTICS - A method and apparatus for encoding information in a reference beacon signal for use in a time-difference-of-arrival/frequency-difference-of-arrival (TDOA/FDOA) geolocation system. Information is encoded in the reference beacon signal using variations in the times and frequencies of sequential reference signal transmissions. The encoded information may include an identifier associated with the transmitter of the reference beacon signal. A geolocation system receiving the reference beacon signal can thus differentiate it from non-cooperative target emissions as well as from other reference beacon signals. | 02-11-2010 |
20100052990 | Portable, Iterative Geolocation of RF Emitters - Iterative geolocation of a stationary RF emitter through the use of TDOA may include the use of a single portable geolocation (e.g., TDOA) sensor, a pair of portable geolocation sensors and three of more portable geolocation sensors. Adding portable geolocation sensors to the iterative process reduces the constraints on the signals to be located as well as providing a reduction in the number of iterations required to obtain improved location accuracy. | 03-04-2010 |
20100090899 | METHOD AND SYSTEM FOR POSITIONING OBJECT WITH ADAPTIVE RESOLUTION - The present invention provides a method and system for positioning an object with adaptive resolution. The method comprises: dividing a space to be detected into Hot Area and General Area; arranging, according to the positions of Hot Area and General Area, high-resolution positioning signal (US) transceivers and low-resolution positioning signal (RF) transceivers, wherein the detection scope of the low-resolution positioning signal transceivers covers the space and the detection scope of the high-resolution positioning signal transceivers covers the Hot Area; and when the object moving in the space, fusing the detection results from the high-resolution positioning signal transceivers and the low-resolution positioning signal transceivers to determine the position of the object with adaptive resolution. With the system of the present invention, for different areas, the object can be positioned with different positioning resolutions (precisions or granularities). Also, since it is not necessary to use a great deal of high-precision positioning devices, the system cost can be reduced considerably. | 04-15-2010 |
20100103047 | METHOD FOR MEASURING DISTANCE AND POSITION USING SPREAD SPECTRUM SIGNAL, AND AN EQUIPMENT USING THE METHOD - By using the delay profile created by delay profile creating section | 04-29-2010 |
20100117906 | Systems, Apparatus, and Methods for Providing and Detecting Information Regarding a Person, Location, or Object - An apparatus for providing and detecting information regarding a person, location, or object includes a power supply, a helicoil dipole antenna, a transmitter, a receiver configured to receive signals from remote transmitters at a designated frequency, a computer processor, and a memory device configured to store an identifier associated with the apparatus. Logic instructions embedded on the memory device are configured to compare an identifier decoded from received signals to the identifier associated with the apparatus. When the identifier decoded matches the identifier associated with the apparatus, the instructions decode a return frequency from the signal, and generate return signals. The return signals include the identifier associated with the apparatus, the transmitter is activated only when the transmitter transmits the return signals at the return frequency. | 05-13-2010 |
20100141529 | SET MODE PASSIVE LOCATION IN TOA/TDOA MODES - The present invention addresses the resolving of the problems associated with the passive location of targets in TOA (Time of Arrival) or TDOA (Time Difference of Arrivals) mode. The method of passively locating a target in TOA or TDOA mode implements a meshing (subdivision) into blocks of the space in which the location area is situated. The set of the blocks that form this mesh is analyzed iteratively. On each iteration, each block of interest is subdivided into smaller identical subblocks. A block of interest is, according to the invention, a block including at least one point belonging to the location area being sought for which the shape is to be determined. The iterative process is stopped when the size of the subblocks obtained on the current iteration corresponds to the desired resolution. The invention applies in particular to the 2D or 3D location systems that include TOA and TDOA modes or mixed modes. | 06-10-2010 |
20100220012 | System and method to range using multi-carrier phasing synchronization - A system and method establishes the time of flight and thereby distance between two transceivers on various media, including but not limited to vacuum, air, electrical wire, optical fiber; using carrier waves sent from one or more transmitters or transceivers to one or more receivers or transceivers. Carriers are arranged to allow the extraction of channel information and maintain acceptable peak to average ratios in an OFDM system. | 09-02-2010 |
20100225541 | Ultra-wideband radios for time-of-flight-ranging and network position estimation - This invention provides a novel high-accuracy indoor ranging device that uses ultra-wideband (UWB) RF pulsing with low-power and low-cost electronics. A unique of the present invention is that it exploits multiple measurements in time and space for very accurate ranging. The wideband radio signals utilized herein are particularly suited to ranging in harsh RF environments because they allow signal reconstruction in spite of multipath propagation distortion. Furthermore, the ranging and positioning techniques discussed herein directly address many of the known technical challenges encountered in UWB localization regarding synchronization and sampling. In the method developed, noisy, corrupted signals can be recovered by repeating range measurements across a channel, and the distance measurements are combined from many locations surrounding the target in a way that minimizes the range biases associated to indirect flight paths and through-wall propagation delays. | 09-09-2010 |
20100259448 | METHOD AND SYSTEM FOR HEALTH MONITORING OF AN OVER THE AIR GEO-LOCATION SYSTEM - A method for testing each one of a plurality of receiving sites operative in a time difference of arrival geo-location system. The method comprises determining a theoretical time of arrival of a test message at each receiving site assuming the test message was transmitted from a test message transmitting antenna at a known location; determining a measured time of arrival of the test message at each receiving site, the test message transmitted from the test message transmitting antenna; determining a true time of arrival of the test message at each receiving site, the true time of arrival comprising the measured time of arrival less a start time of the test message; determining a difference between the theoretical and the true times of arrival for each receiving site, wherein the difference for each receiving site is indicative of a health of the receiving site. | 10-14-2010 |
20100283682 | CLOCK PHASE RANGING METHODS AND SYSTEMS - A system and method for estimating the range between two devices performs two or more ranging estimates with subsequent estimates performed using a clock that is offset in phase with respect to a prior estimate. The subsequent estimate allows estimate uncertainties due to a finite clock resolution to be reduced and can yield a range estimate with a higher degree of confidence. In one embodiment, these additional ranging estimates are performed at n/N (for n=1, . . . N−1, with N>1 and a positive integer) clock-period offset introduced in the device. The clock-period offset can be implemented using a number of approaches, and the effect of clock drift in the devices due to relative clock-frequency offset can also be determined. To eliminate the bias due to clock-frequency offset, a system and method to estimate the clock-frequency offset is also presented. | 11-11-2010 |
20100295731 | METHOD FOR OPTIMUM BANDWIDTH SELECTION OF TIME-OF-ARRIVAL ESTIMATORS - A method determines an optimum bandwidth that minimizes ranging error in a geolocation application. The method ensures that an optimum bandwidth is selected under all channel conditions (i.e., both line-of-sight (LOS) and non-LOS (NLOS) conditions). Additionally, the method is generic and system-independent, such that it is applicable to both coherent receivers (e.g., match filter (MF) based receivers), non-coherent receivers (e.g., energy detector (ED) based receivers) and any types of time-of-arrival (TOA) estimators (e.g., whether peak-detection or threshold-based TOA estimator), regardless of the signal-to-noise ratios (SNRs) under consideration. | 11-25-2010 |
20100309053 | RADIO POSITIONING AND RANGING SYSTEM AND POSITIONING AND RANGING PROGRAM - A positioning and ranging system includes a transmitter transmits a plurality of impulses; and a receiver receives the impulses; the receiver includes an initial detection unit records a sensing time of a first impulse among a plurality of impulses transmitted by the transmitter; a sensing margin detection unit for detecting a sensing margin being a difference between a field intensity of the first impulse and a reception limit field intensity of the receiver; a correction unit identifies a sensing error differential time based on a given relationship between the sensing margin and the sensing error differential time, and corrects the sensing time detected by the initial detection unit using the identified sensing error differential time; the system measures a distance between the transmitter and the receiver and a position of the transmitter based on a time the transmitter transmits the first impulse and a time the receiver receives the impulse. | 12-09-2010 |
20100315291 | METHOD AND APPARATUS FOR BOUNDED TIME DELAY ESTIMATION - A method and apparatus for estimating the position of a mobile device in a multi-path environment. In one example, the method includes receiving a plurality of reference signals from a corresponding plurality of reference devices, for each reference signal, calculating expected time delay boundaries, for each reference signal, estimating a range between the device and the corresponding reference device based on a measured time delay of the reference signal falling within calculated time delay boundaries to produce a plurality of range estimates, and filtering the plurality of range estimates to generate a composite estimate of the position of the device. | 12-16-2010 |
20100321239 | METHOD AND APPARATUS FOR THE PASSIVE LOCATION OF RADIO SIGNAL TRANSMITTERS - A method for locating sources emitting radio signals comprises arranging at least one first pair and one second pair of receiving antennae; arranging at least one additional receiving antenna; synchronizing all the antennae; acquiring with at least three antennae and/or at least two pairs of antennae, radio signals emitted by the source; digitally processing with each antenna, the signal received and generating a short report; sending with each antenna, the track report to a central processing unit; processing the track reports to form a global track file; sending to the antennae with the central processing unit, a suitable command for collecting data; digitally processing with each antenna, the signal received from the specific source and generating and storing a pulse report; sending the pulse reports to the central processing unit; calculating the TDOA for each signal; selecting and applying the procedure for identifying the coordinates of the transmitting antenna. | 12-23-2010 |
20110025562 | Tightly Coupled UWB/IMU Pose Estimation System and Method - A six-degree-of-freedom (6DOF) tracking system adapts aspects of Ultra-Wideband (UWB) measurement and microelectromechanical systems (MEMS) inertial measurements within a unique tightly coupled fusion algorithm to accurately and efficiently measure an object's position as well as orientation. The principle of operation of the system protects against the negative effects of multipath phenomenon and non-line-of-sight (NLOS) conditions, allowing a more robust position and orientation tracking system. | 02-03-2011 |
20110043406 | FINDING THE POSITION OF A MOBILE TERMINAL - A method and apparatus are disclosed for determining the position, or change in the position, of a mobile terminal. The terminal has a receiver for receiving the signals from one or more transmission sources at unknown positions and an independent positioning device able to find, when operative, the position of the mobile terminal. The method uses the independent positioning device to measure the position of the mobile terminal at one or more first locations. A respective first set of time or phase offset values of signals received from the transmission sources relative to each other or to a reference in the mobile terminal is measured in the mobile terminal, at each first location. A second set of time or phase offset values are measured in the mobile terminal at a second terminal location where the independent positioning device is not operative and a second set of time or phase offset values of the signals received from the transmission sources, relative to each other or to a reference in the mobile terminal is measured. The values and said first measured terminal position or positions are combined, to thereby calculate the position of the mobile terminal at the second location, or the change in position of the mobile terminal between a first location and the second location. | 02-24-2011 |
20110050501 | LOCATION SYSTEM AND METHOD WITH A FIBER OPTIC LINK - A TDOA (time difference of arrival) location system, in which mobile wireless devices broadcast wireless signals which are received by two or more transceivers deployed in the vicinity of the mobile wireless device. Each transceiver measures the TOA (time of arrival) of the received broadcasted signal and reports the TOA to a central server. The central server then calculates the mobile device position using multi-lateration of TDOA values. The system uses fiber optic links between the antennas and the transceivers deployed in the location area to provide unique advantages that couldn't be achieved using RF coaxial cables. | 03-03-2011 |
20110074632 | WIRELESS POSITIONING METHOD AND APPARATUS - A wireless positioning method of a receiver is provided. Signals are received from a plurality of transmitters, propagation taps of the plurality of transmitters received from the plurality of transmitters are determined, respectively, the distance between the receiver and each of the transmitters is calculated, respectively, the weight of each of the transmitters is calculated by using each of the propagation delay tap, the distance is adjusted by using the weight of each of the transmitters, and an area, in which circles away by the adjusted distances between the receiver and each of the transmitters on the basis of each of the transmitters overlap with each other, is estimated as the location of the receiver. Thus, an error of wireless positioning according to a propagation environment can be reduced. | 03-31-2011 |
20110140966 | METHOD OF MULTI-TRANSMITTER AND MULTI-PATH AOA-TDOA LOCATION COMPRISING A SUB-METHOD FOR SYNCHRONIZING AND EQUALIZING THE RECEIVING STATIONS - Method and system for locating one or more transmitters in the potential presence of obstacles in a network comprising a first receiving station A and a second receiving station B that is asynchronous with A. The method includes the identification of a reference transmitter through an estimation of its direction of arrival AOA-TDOA pair (θ | 06-16-2011 |
20110148709 | SIGNAL PATH DELAY DETERMINATION - Propagation time for a target signal path is determined by detecting and processing a plurality of unknown signals received at two locations. A third location is established, such that the propagation time between the third location and one of the two locations is known, and the signal path between the third location and the other of the two locations is the target signal path. The two locations are monitored for any signals that may be detected. Signals received at the two locations are processed to determine which signals have a common source, and of the signals having a common source, the signal having the greatest delay between times of reception at the two locations is selected. The selected signal is used to determine the propagation time between the two locations. | 06-23-2011 |
20110181469 | METHOD AND APPARATUS FOR DETERMINING THE CHANGING POSITION OF A MOBILE TRANSMITTER - A method and a device for determining the changing position of a mobile transmitter in a three-dimensional space is proposed in which transmitted signals are issued at a pre-determined frequency from a mobile transmitter, wherein a plurality of receivers receive said transmitted signals. An evaluation device evaluates the received signals for generating correlation curves between the transmitted and the received signals. From the curves of magnitude versus time, TOA values are determined, and from curves in the complex plane, phase values are determined using the time information from the TOA values. The position of the mobile transmitter is calculated as a function of TOA values and of phase or phase difference values. | 07-28-2011 |
20110205122 | Method and Arrangement of Determining Timing Uncertainty - A network node such as a positioning node, and a related method of determining an uncertainty of a timing measurement used for positioning of a wireless device are disclosed. The method includes estimating a timing measurement uncertainty, and determining if an uncertainty reducing measurement is available. If an uncertainty reducing measurement is available, the method also comprises determining a timing measurement uncertainty based on the estimated timing measurement uncertainty and the uncertainty reducing measurement. | 08-25-2011 |
20110221632 | High-precision radio frequency ranging system - 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 full-duplex configuration. The method produces accurate estimates of the distance between two radios. | 09-15-2011 |
20110254735 | SIGNAL PATH DELAY DETERMINATION - Propagation time for a target signal path is determined by detecting and processing a plurality of unknown signals received at two locations. A third location is established, such that the propagation time between the third location and one of the two locations is known, and the signal path between the third location and the other of the two locations is the target signal path. The two locations are monitored for any signals that may be detected. Signals received at the two locations are processed to determine which signals have a common source, and of the signals having a common source, the signal having the greatest delay between times of reception at the two locations is selected. The selected signal is used to determine the propagation time between the two locations. | 10-20-2011 |
20110267234 | RANGING DIVERSITY-RECEPTION METHOD AND RECEIVER - Method for determining an arrival time of a RF ranging signal at a ranging receiver, comprising receiving at least one RF ranging signal via a plurality of antennas comprised by the ranging receiver, providing a plurality of antenna signals, each comprising at least a section of the ranging signal as received either by a respective one of the antennas or by a linear combination of at least two of the antennas, determining respective candidate arrival times of the at least one ranging signal from at least two of the antenna signals and determining the arrival time of the at least one ranging signal as the earliest candidate arrival time. | 11-03-2011 |
20110285589 | Network Location and Synchronization of Peer Sensor Stations in a Wireless Geolocation Network - Transmitters are located with a network of sensors by measuring signal characteristics at multiple known locations and processing these measurements at a central node. The sensors communicate their location to the central node along with measured characteristics of the transmitter's signal, and may be required to synchronize with other sensors. Often, GNSS receivers are utilized to locate and synchronize the sensors. However, the GNSS signals may be attenuated by obstructions. In this case, the sensors determine their location by making ranging measurements with sensors that can receive the GNSS signals. The waveform for the wireless backhaul permits this ranging. Additionally, many sensors can determine their location and time synchronize with the geolocation network through reception of signals from other sensors even if they do not have a direct connection to sensors that know their location and are time synchronized. | 11-24-2011 |
20110304506 | Method For Measuring Location of Mobile Terminal - A method for measuring a location of a mobile terminal includes calculating first location information by using a ToA (Time of Arrival) scheme, calibrating the first location information by using angle information between two base stations and the terminal; calculating second location information by using an AoA (Angle of Arrival) scheme, and calculating a location value of the terminal by using the calibrated first location information and the second location information. | 12-15-2011 |
20110316747 | LEADING EDGE DETECTION - A leading edge associated with a received signal is detected to provide, for example, time of arrival information for a ranging algorithm. In some aspects, a method of leading edge detection involves sampling a received signal, generating a drift compensated signal based on the samples, reconstructing the received signal based on the drift compensated signal, and identifying a leading edge associated with the received signal based on the reconstructed signal. | 12-29-2011 |
20120019413 | System and method for real-time locating - A locating system, includes at least one initiator configured to operate at a first clock frequency, and to transmit a measurement signal including a first preamble; and at least one transponder configured to operate at a second clock frequency, to receive the measurement signal, and to transmit a response signal to the initiator, the response signal including a second preamble. The initiator is further configured to calculate, based on the response signal, a distance between the initiator and the transponder for determining a location of the transponder. | 01-26-2012 |
20120026041 | SYSTEMS AND METHODS FOR LOCATING A TARGET IN A GPS-DENIED ENVIRONMENT - A system for locating an object in a GPS-denied environment includes first and second stationary nodes of a network and an object out of synchronization with a common time base of the network. The system includes one or more processors that are configured to estimate distances between the first stationary node and the object and a distance between the second stationary node and the object by comparing time-stamps of messages relayed between the object and the nodes. A position of the object can then be trilaterated using a location of each of the first and second stationary nodes and the measured distances between the object and each of the first and second stationary nodes. | 02-02-2012 |
20120162014 | SYSTEM AND METHOD FOR AIRCRAFT NAVIGATION USING SIGNALS TRANSMITTED IN THE DME TRANSPONDER FREQUENCY RANGE - The present invention provides a system and method for aircraft to determine own position and navigate using a navigation heartbeat signal broadcast on a DME uplink and/or a Mode-S uplink frequency. The present invention enables deep integration between the existing navigation systems (DME interrogation-reply ranges and GPS/WAAS raw TDOA or pseudo range measurements) and the DME heartbeat TDOAs or Mode-S heartbeat TDOAs to provide a highly accurate navigation positioning capability and provide necessary backup capability in lieu of GPS to maintain the necessary RNP/RNAV capability and avoid degrading aircraft operational safety. | 06-28-2012 |
20120194387 | TRACKING RADIO SIGNAL SOURCES - A method and system of determining the position of a radio signal transmitter are described. The method includes determining the type of radio signal being transmitted from the radio signal transmitter by analysing radio signal characteristics and correlating different sets of information to determine the position of the radio signal transmitter. Each set of information corresponds to a different relative position of at least one receiver to the transmitter and includes radio signal data derived from radio signals received by the at least one receiver from the transmitter at each respective relative position and positioning data containing information about the position of the at least one receiver at each respective relative position. | 08-02-2012 |
20120262339 | Determination of State Vector, Timing, and Navigation Quality Metrics from Reception of ADS-B Transmissions - A technique for determining the position of a mobile device includes receiving messages from respective mobile reference devices. Each of the messages is broadcast beginning at one of several predetermined message start opportunity (MSO) times that have known timings relative to a reference time. Each of the messages contains a MSO value identifying the MSO time at which transmission of the message started. The MSO value is used to determine the time of transmission of each of the messages received at the mobile device, and the position of the mobile device is determined via multi-lateration. According to another approach, the mobile device receives a set of ADS-B messages from a respective set of mobile reference devices. The time of transmission of each of the ADS-B messages is supplied in the ADS-B message itself or in a subsequent message and used to determine the position of the mobile device. | 10-18-2012 |
20120293371 | System and Method for Geolocation of Multiple Unknown Radio Frequency Signal Sources - According to an embodiment of the present invention, geolocations of multiple unknown radio frequency (RF) signal sources are determined using three-dimensional (3-D) geolocation techniques. The three-dimensional (3-D) geolocation techniques obtain reliable geolocation estimates of radio frequency (RF) emitters based on energy or received signal strength (RSS) of emitter transmitted signals and based on their time differences of arrival (TDOAs) at various sensor locations. The energy based geolocations and the time difference of arrival (TDOA) geolocations are combined to determine an overall set of geolocations for multiple unknown radio frequency (RF) signal sources. The geolocation information is used to track and monitor the locations of the multiple emitters. | 11-22-2012 |
20130057434 | Cell Organization and Transmission Schemes in a Wide Area Positioning System (WAPS) - A position location system comprises transmitters that broadcast positioning signals. Each broadcasted positioning signal comprises a pseudorandom ranging signal. The position location system includes a remote receiver that acquires and measures the time of arrival of the positioning signals received at the remote receiver. During an interval of time, at least two positioning signals are transmitted concurrently by the transmitters and received concurrently at the remote receiver. The two positioning signals have carrier frequencies offset from one another by an offset that is less than approximately twenty-five percent of the bandwidth of each positioning signal of the two positioning signals. Cross-interference between the positioning signals is reduced by tuning the remote receiver to a frequency of a selected signal of the two positioning signals and correlating the selected signal with a reference pseudorandom ranging signal matched to a transmitted pseudorandom ranging signal of the selected signal. | 03-07-2013 |
20130063307 | Cell Organization and Transmission Schemes in a Wide Area Positioning System (WAPS) - A position location system comprises transmitters that broadcast positioning signals. Each broadcasted positioning signal comprises a pseudorandom ranging signal. The position location system includes a remote receiver that acquires and measures the time of arrival of the positioning signals received at the remote receiver. During an interval of time, at least two positioning signals are transmitted concurrently by the transmitters and received concurrently at the remote receiver. The two positioning signals have carrier frequencies offset from one another by an offset that is less than approximately twenty-five percent of the bandwidth of each positioning signal of the two positioning signals. Cross-interference between the positioning signals is reduced by tuning the remote receiver to a frequency of a selected signal of the two positioning signals and correlating the selected signal with a reference pseudorandom ranging signal matched to a transmitted pseudorandom ranging signal of the selected signal. | 03-14-2013 |
20130093625 | Deployable intelligence and tracking system for homeland security and search and rescue - This invention builds on previous industry techniques to correlate data from a variety of sources for the purposes of tracking and identifying aircraft, vehicles, and marine vessels in real time over a variety of different areas including oceans and mountainous terrain. Passive broadband tracking of aircraft emitters, and electronic fingerprinting of emitters, correlated with audio, video, infrared, primary radar and other information is employed to provide a comprehensive assessment of an aircraft's position, track and identification for a variety of applications including homeland security and search and rescue. | 04-18-2013 |
20130106657 | METHOD AND SYSTEM FOR DETERMINING A TIME DIFFERENCE, METHOD AND SYSTEM FOR FINDING A POSITION OF A TRANSMITTER | 05-02-2013 |
20130135148 | FEMTOCELL CALIBRATION FOR TIMING BASED LOCATING SYSTEMS - Systems and methods disclosed herein can implement a femtocell calibration solution that uses the known location of the femtocell to calibrate timing based locating systems. The calculated time differences of different signals sent between macrocells and a mobile device can be used to solve for a reference time difference that accounts for the timing differences of the unsynchronized macrocells. The reference time difference can then be used to solve for the location of another mobile device if the calculated time differences between that mobile device and the macrocells are known. The solution can include taking many measurements of the calculated time difference at the first mobile device in order to average them to get a more accurate reference time difference. The solution can further include ceasing measurements at the first mobile device when the mobile device is no longer within range of the femtocell. | 05-30-2013 |
20130162480 | Optimization of Variable Coherence Integration for the Location of Weak Signals - In a network-based Wireless Location System (WLS), geographically distributed Location Measurement Units (LMUs) must be able to detect and use reverse channel (mobile to network) signals across multiple BTS coverage areas. By using Matched Replica correlation processing with the local and reference signals subdivided into discrete segments prior to correlation, the effects of mobile clock drift and Doppler shifts can be mitigated allowing for increased processing gain. By using historical network and real-time data about the radio signal and/or radio channel, the segmentation and computation scheme may be optimized to reduce latency and enhance capacity while maximizing location accuracy. | 06-27-2013 |
20130176174 | Method and System for Estimating Time of Arrival of Signals Using Maximum Eigenvalue Detection - A method estimates the time-of-arrival (ToA) of signals received via multipath channels. The received signal of a number of trials is first passed through a band-pass filter and then sampled. The presence of a channel tap within a time window is estimated by comparing a threshold to a largest eigenvalue of the covariance matrix of a time window. The signal samples are used to calculated a band region of a complete covariance matrix. After the band region has been updated for all signal samples, the covariance matrices for a moving window can be extracted from the band region. The ToA is estimated as the ending time of the leading window, which is the earliest window, such that the largest eigenvalue is larger than a given threshold. | 07-11-2013 |
20130222185 | Method and System for Using Indirect Paths of Ultra Wideband Signals to Localize a Wireless Communication Node on a Body. - A method and a system are provided which are able to utilize indirect paths of signals of UWB type to locate a wireless communication node possessed by a body. The present method and system can notably apply to cooperative body networks implementing several wireless nodes able to communicate with one another. | 08-29-2013 |
20130241774 | WIRELESS POSITIONING SERVER USING CLOCK OFFSET CALIBRATION AND WIRELESS POSITIONING METHOD USING THE SAME - A wireless positioning server using clock offset compensation and a wireless positioning method using the same. The wireless positioning server using clock offset compensation estimates a precise position of a tag requiring position information by effectively predicting information regarding a distance between a beacon for performing positioning and the tag requiring position information. An error in the positioning estimation result due to a clock offset is minimized by measuring a relative clock frequency ratio between beacons and by compensating for clock frequencies of the beacons when a distance between a beacon and a tag is estimated. | 09-19-2013 |
20140062791 | LOCALIZATION METHOD OF SOURCE OF UNKNOWN SIGNAL BASED ON TDOA METHOD - Disclosed is a localization method of a source of unknown signal based on a TDOA method, comprising a data obtaining step S | 03-06-2014 |
20140104109 | GNSS Reception Using Distributed Time Synchronization - A GNSS receiver communicates with any connectivity device, such as a WiFi device that is, in turn, in communication with a wired network having access to the DTI timing. Such connectivity devices may set their timing and frame synchronization to the DTI and thus serve as Geopositioning beacons, thereby enabling the GNSS receiver to accurately determine its position. The GNSS receiver may also use the DTI timing supplied by such a network to perform relatively long integration time so as to achieve substantially improved sensitivity that is necessary for indoor Geopositioning applications. Furthermore, the GNSS data, such as satellite orbital information, may also be propagated by such devices at high speed. By providing this data to the GNSS receivers via such connectivity devices in a rapid fashion, the GNSS receivers are enabled to receive the transmitted data associated with the satellite without waiting for the GNSS transmission from the satellites. | 04-17-2014 |
20140253385 | COMMUNICATION STATION AND METHOD FOR TIME-OF-FLIGHT POSITIONING USING COOPERATING STATIONS - Embodiments of a communication station and method for time-of-flight (ToF) positioning in a wireless network are generally described herein. In some embodiments, a ToF cooperation table may be received by a positioning station from an access point. The ToF cooperation table may identify one or more cooperating stations and may include information about each cooperating station for ToF positioning. A ToF positioning protocol may be performed with at least some of the cooperating stations identified in the ToF cooperation table using the information in the ToF cooperation table. During the ToF positioning protocol, a current position and a station positional accuracy may be received from each cooperating station. The current position may be a position when ToF is measured. A location of the positioning station may be determined based on the current positions and the ranges to each of the cooperating stations determined from the ToF positioning protocol. | 09-11-2014 |
20140253386 | DEVICES, METHODS, AND APPARATUSES FOR COMPUTING ROUND-TRIP TIME OF A MESSAGE - Methods, apparatuses, and/or articles of manufacture are disclosed, which may be employed in a mobile device communicating with a transponder via a near field communications channel. In one example, round trip time of a message may be computed to estimate processing latency contributed by processes occurring within the mobile device and/or the transponder. | 09-11-2014 |
20140266907 | Geolocation with Radio-Frequency Ranging - A geolocation system includes an originator device configured to transmit a first wireless signal to a transponder device. The transponder device is configured to transmit a second wireless signal to the originator device. The system includes at least one observer device configured to receive the first wireless signal from the originator device and receive the second wireless signal from the transponder device. The system also includes a first processor configured to calculate a transactional difference range at the at least one observer device based on the first wireless signal received at the observer device and the second wireless signal received at the observer device. A corrected transactional difference range value may be calculated by subtracting a time-of-flight of the first wireless signal from the originator device to the transponder device from the transactional difference range. A method of performing geolocation using a transactional difference range is also disclosed. | 09-18-2014 |