Abstract: An apparatus for localizing a position on a path, radio signals of fixedly positioned radio transmitters being receivable along the path, the apparatus including a determiner for determining properties of the radio signals of the fixedly positioned radio transmitters at the position, and a comparator for comparing the determined electromagnetic properties with previously recorded properties which characterize a reference path, and for determining a relation between the position and the reference path on the basis of a result of the comparison.

Abstract: The present invention provides a method, system, and apparatus for rapidly acquiring and correlating synchronization codes for a mobile receiver used for position determination purposes. The receiver uses a processing unit to perform the correlation functions. The processing unit first computes, for each segment interval of the received signal, the phase offset of that interval. Each interval is appropriately adjusted to account for the computed phase offset. The processing unit then accumulates the phase-adjusted segment intervals, and may down-convert the accumulated signal to a baseband format from an intermediate frequency. The processing unit then correlates the accumulated signal with a reference signal to produce a correlation peak, from which the time delay of a synchronization code within the interval can be calculated. Ultimately, the receiver's position can be determined based on the calculated time delay.

Abstract: Systems, methods, and device are provided for network and network device management. One method embodiment includes receiving information associated with a network device. The method further includes analyzing the network information using a Kalman filter.

Abstract: Techniques for accurate position location and tracking suitable for a wide range of facilities in variable environments are disclosed. In one aspect, a system for position location comprises a plurality of sensors (e.g. a network monitor, an environment sensor) for generating measurements of a plurality of sources, a plurality of objects or tags, each object generating measurements of the plurality of sources, and a processor for receiving the measurements and generating a position location for one or more objects in accordance with the received measurements. In another aspect, a position engine comprises a mapped space of a physical environment, and a processor for updating the mapped space in response to received measurements. The position engine may receive second measurements from an object within the physical environment, and generate a position location estimate for the object from the received second measurements and the mapped space.

Abstract: A space-time calibration system and method implement space-time solutions, in which, in one preferred embodiment, a single node determines its own space-time solutions based on other network nodes with which the single node communicates. In other preferred embodiments, space-time solutions for the node can be generated using other resources in the network. The disclosed system and method enable reliable, precise object positioning particularly for environments where the Global Positioning System (GPS) is blocked or subject to interference such as within the urban core.

Abstract: A positioning system that includes a plurality of chronologically synchronized Time Division Multiple Access (TDMA) Positioning-Unit Devices and a position receiver incorporating a TDMA Adaptive Directional Antenna Array is disclosed. The plurality of chronologically synchronized Positioning-Unit Devices, positioned at known locations, transmit positioning signals in a predetermined Time Division Multiple Access (TDMA) sequence, such that each Positioning-Unit Device has a unique transmission time slot. The TDMA Adaptive Directional Antenna Array is configured to consecutively steer a directional receive antenna in spatial synchronization with the plurality of Time Division Multiple Access (TDMA) Positioning-Unit Device transmissions, such that the directional receive antenna is oriented toward the currently transmitting Positioning-Unit Device, or the directional receive antenna is oriented toward the origin of the currently received positioning signal.

Abstract: Communication between a remote locator and a transponder is used to determine the relative position of the transponder. The transponder and locator each include a transmitter and a receiver. The locator transmits an inquiry in the form of a relatively powerful cyclically encoded signal with repetitive elements, uniquely associated with a target transponder. Periodically, each transponder correlates its coded ID against a possible inquiry signal, determining frequency, phase and framing in the process. Upon a match, the transponder transmits a synthesized response coherent with the received signal. The locator integrates multiple cyclical response elements, allowing low-power transmissions from the transponder. The locator correlates the integrated response, determines round-trip Doppler shift, time-of-flight, and then computes the distance and angle to the transponder. The transponder can be wearable, bionically implanted, or attached to, or embedded in, some object.

Abstract: A system and method for determining the position of people and/or objects, whether mobile or stationary, is presented herein. The system uses fixed and/or portable FM transmitters to transmit synchronized signals. These signals are acquired by a Receiver device which uses the signal timing to perform Time Difference of Arrival calculations to determine the Receiver's location. Then, using some arbitrary communications method, such as wireless communications, the Receiver device can forward its location to some arbitrary type of application system.

Abstract: A positioning receiver is shown having one or more receiving channels for receiving a signal from a positioning station, a controlling element for controlling the reception of the signal from the positioning station, and a clock generator for generating a clock signal for said controlling element. The positioning receiver also has a sampler for taking samples at least first and second sampling rates, and a selector for selecting samples from the samples taken at the at least first and second sampling rates, to be used in the controlling element, for controlling signal reception. Furthermore, the invention relates to a system, a wireless communication device, a module, a method, and a computer software product.

Abstract: In determining a location estimate for a communications device, at least one first location estimate is determined based on information relating to signals transmitted between the communications device and at least one first antenna of a communications system. At least one second antenna of the communications system is determined, the at least second antenna not used for communication by the communications device. Thereafter, a second location estimate for the communications device is determined based at least on the at least one first location estimate and information relating to the at least one second antenna.

Abstract: To provide a method of measuring a position of a node by using a radio communication system which comprises the node to send a position measuring signal, and a plurality of base stations to receive radio signals from the node, the method including: the base stations watching signals from the node through a predetermined channel; at least one of the base stations sending a reference signal after receiving of the position measuring signal; at least two of the base stations measuring the reception timing of the position measuring signal and the reception timing of the reference signal; and calculating the position of the node by using the reception timing of the position measuring signal and the reference signal measured by the base stations which have received the reference signal, and position information of the base station which has received the position measuring signal.

Abstract: A system and method for effectively performing enhanced device location procedures to determine the current physical location of a mobile device includes a plurality of satellites that wirelessly transmit satellite beacon signals, a plurality of base stations that wirelessly transmit pilot signals, and a plurality of access points that wirelessly transmit access-point beacon signals. A location detector of the mobile device coordinates a device location procedure by measuring the satellite beacon signals, the pilot signals, and the access-point beacon signals to generate corresponding satellite information, base station information, and access point information. The location detector analyzes the satellite information, the base station information, and the access point information to select an optimal system configuration from the most effective satellites, base stations, and access points.

Abstract: A secure localization method for wireless networks utilizes access point variable transmission power capability to transmit encoded localization signals at different power levels to a wireless device in the network. Based on the particular combination of encoded signals collected by the wireless device and reported back to a network controller, the location of the wireless device may be determined in conjunction with information contained in a location database.

Abstract: Apparatus and method for tracing a geographical journey taken by an entity, for example an article (shipment), asset or person, on a worldwide map uses a miniature, passive, low power, radio receiver tag that is attached to the entity and collects multiple FM spectra during the travels of the entity. When the tag is retrieved at the end of the journey, the FM spectra are downloaded and compared against a collection of constructed spectra constructed from antenna transmission and location data derived. Correlating each of the spectra collected by the receiver tag with the corresponding spectra in the database allows the regions traversed by the receiver tag, and hence the entity, during its travels to be plotted.

Abstract: In a local positioning system, a receiver is adapted for receiving signals from a land-based transmitter. The receiver includes an analog decorrelator for decorrelating the transmitted spread spectrum signals. A down converter connected with an antenna may be spaced away from other portions of the receiver. The down converter down converts received ranging signals and provides them to the remotely spaced receiver portions. A signal line connecting the down converter to the receiver may be operable to transmit any two or more of a reference signal provided to the down converter, the down converted intermediate frequency signals provided to the receiver, and power provided to the down converter. The receiver may be positioned adjacent to or as part of a land-based transmitter. By determining positions of two or more antennas, the location of the associated transmitter is determined.

Abstract: The location of a medical device is determined by receiving one or more signals at the medical device transmitted by one or more beacons, respectively, at known locations. The one or more signals received at the medical device are sent from the medical device to a processor, which determines the location of the medical device based on the received one or more signals. One of the beacons may be a portable patient beacon, the location of which is determined when its signal is received by a medical device, the location of which was previously determined.

Abstract: A method for determining the positions of targets by bistatic measurements using signals scattered by the targets is provided in which the velocities of the targets can also be determined. The range of the transmitters is selected so that a target at an arbitrary point can be measured, by scattering in the target, by at least four cooperating measuring facilities. First the targets are associated by calculating, in two independent ways, two sets of sums of distances between transmission points and targets and, respectively, targets and reception points. Subsequently, the two sums are sorted with respect to distance, compared with each other, and the sums that correspond with each other within a predetermined margin of error are stated to correspond to conceivable targets. The association of targets is improved and completed by corresponding calculations being carried out for Doppler velocities.

Abstract: Methods and systems for providing an improved geolocation of a plurality of transmitters are disclosed. In one embodiment, a method for providing a geolocation of a plurality of transmitters includes determining a relative location of each transmitter in the plurality of transmitters with respect to at least one other transmitter in the plurality of transmitters; determining an initial geolocation of the plurality of transmitters; computing a calibration factor by comparing the initial geolocation of the plurality of transmitters to the relative locations of the plurality of transmitters; and determining a calibrated geolocation of the plurality transmitters by adjusting at least one final geolocation of the plurality of transmitters by the calibration factor.

Abstract: A precise positioning method and system is disclosed wherein at least one ground transmitter is used for transmitting a ranging signal with code modulation. The at least one ground transmitter is configured to receive a signal from at least one satellite and a second ground transmitter. The at least one ground transmitter measures a code phase of the received signals. The measured code phase information is communicated to a rover that is associated with a user. The rover can determine the user's precise position based on the measured code and/or carrier phase information and a clock correction model.

Abstract: A system and method for monitoring topological changes in a defined area. A grid of sensors is arranged in the area, with known distances between them. The sensors communicate wirelessly with a host computer, which individually addresses each sensor to instruct that sensor to be in an interrogate mode or responder mode. When a sensor is in interrogate mode, it measures distance from a neighboring sensor using radar (continuous wave phase difference) measurements. When a sensor is in responder mode, it receives, delays, and returns a signal received from a neighboring sensor.

Abstract: A diversity system for positioning systems is disclosed, whereby a plurality of positioning signals, which are transmitted and/or are received from substantially the same location, are received and interpreted by an observing receiver. The observing receiver is configured to compare and then select substantially coherent positioning signals, and/or create a best-fit estimate of the measured positioning signals, such that accurate position measurements can be determined in multipath-affected environments.

Abstract: The present invention discloses a system and method for allowing a position receiver to determine position solutions from positioning signals from a plurality of autonomous positioning networks, each of which is synchronized to a different timebase. Each of the plurality of autonomous networks comprises one or more positioning-unit device, which is a specialized transceiver capable of receiving and interpreting reference positioning signals from a reference transmitter, a position receiver, another positioning-unit device or all. At least one positioning-unit device within a first autonomous positioning network receives positioning signals from at least one positioning-unit device from a second adjacent autonomous positioning network and measures the timebase difference between the second network and the first network and subsequently calculates a timebase clock correction.

Abstract: The present invention discloses a system and method for allowing a position receiver to determine position solutions from positioning signals from a plurality of autonomous positioning networks, each of which is synchronized to a different timebase. Each of the plurality of autonomous networks comprises one or more positioning-unit device, which is a specialized transceiver capable of receiving and interpreting reference positioning signals from a reference transmitter, a position receiver, another positioning-unit device or all. At least one positioning-unit device within a first autonomous positioning network receives positioning signals from at least one positioning-unit device from a second adjacent autonomous positioning network and measures the timebase difference between the second network and the first network and subsequently calculates a timebase clock correction.

Abstract: A method and apparatus for determining the geographic location of a user incorporates the sensing of a plurality of physical environmental parameters at the user's location. The parameter values are compared to corresponding parameter values associated with known locations, and a best-fit correlation is established. The identity of the determined location may be displayed to the user, or may be used to control a location-based operation, such as the unlocking of a safe, the transmission of an entry password, or the disabling of a piece of equipment. Persistence weighting values for different environmental parameters may be applied to improve the reliability of the correlation.

Abstract: Reliable and efficient search windows are provided by allowing the adaptation of the code search window to be dependent on inaccuracy measures of relations between a cellular frame time and a satellite reference time. This inaccuracy is calculated in a positioning node (21) of the cellular communications system (1), preferably by filtering of measurements received from user equipments. Linear trend Kalman filtering followed by post processing of estimation errors is presently preferred. In order to ensure non-ambiguous interpretation of the received time stamps of received satellite signals (55) provided by user equipments (10), a pseudo propagation delay is computed in both the user equipment (10) and the positioning node (21) based on GPS acquisition assistance data. The GPS time stamp is then defined referring to the determined pseudo propagation delay. In a preferred embodiment, the pseudo propagation delay is assured to be situated within a pre-determined time interval.

Abstract: A precise positioning method and system is disclosed for allowing an array of ground transmitters to self-survey their relative location at centimeter-level accuracy by transmitting, amongst the ground transmitters in the array, bi-directional ranging signals associated with a wideband code modulation with a chipping rate faster than 30 MHz.

Abstract: A method, apparatus, and computer-readable media for determining the position of a user terminal comprises receiving at the user terminal a broadcast television signal from a television signal transmitter; determining a first pseudo-range between the user terminal and the television signal transmitter based on a known component of the broadcast television signal; receiving at the user terminal a global positioning signal from a global positioning satellite; determining a second pseudo-range between the user terminal and the global positioning satellite based on the global positioning signal; and determining a position of the user terminal based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

Abstract: An architecture for minimizing calibration effort in an IEEE 802.11 device location measurement system. The calibration technique is based upon a regression function that produces adequately accurate location information as a function of signal strength regardless of gaps in the calibration data or minimally available data. The algorithm takes a set of signal strengths from known room locations in a building and generates a function giving (x,y) as a function of signal strength, which function may then be used for the estimation of new locations. Radial basis functions, which are simple to express and compute, are used for regression. The fact that the algorithm maps signal strength to continuous location makes it possible to skip rooms during calibration, yet still evaluate the location in those rooms.

Abstract: A method and apparatus for locating position of a GPS device is described. In one example, a method for provisioning a mobile device with a model for determining a position of the mobile device in at least one geographic area is provided. The method includes obtaining an estimate of the position of the mobile device, forming one or more satellite orbit models from the estimate and a wide area model, and sending the at least one satellite orbit model to the mobile device. The wide area model is formed from measurements from a plurality of satellites of a Global Positioning System, and the measurements are obtained by a plurality of reference stations.

Abstract: A method for determination of a repeater time delay in a mobile communication network, without affecting a correct positioning of a mobile terminal, is disclosed.

Abstract: 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.

Abstract: A method for trilateration may include receiving a signal via each of a plurality of LOS paths and predicting performance of each LOS path. The method may also include filtering out signals received via LOS paths with performance below a predetermined threshold value. The method may further include performing trilateration using unfiltered signals to substantially determine a location of a device.

Abstract: Methods and apparatus to monitor consumer activity are disclosed herein. In a disclosed example method, a first signal is received via a portable device from a first one of a plurality of stationary devices positioned throughout a monitored environment. A first stationary device location of the first stationary device is determined based on the first signal. Absolute location information indicative of a first portable device location of the portable device is determined based on the first stationary device location. Navigational sensing information is generated by the portable device. Relative location information is determined based on the absolute location information and the navigational sensing information, wherein the relative location information is indicative of a second portable device location of the portable device.

Abstract: A broadcast digital transmission (BDT) receiver, computer-readable media, and associated method for receiving and processing of BDT signals from a plurality of transmitters. A BDT receiver includes an antenna to intercept broadcast radio signals and an analog front-end to down-convert it to a suitable frequency for digitization. A baseband signal processor acquires and tracks designated codes in BDT signals using a generalized correlator to produce time of arrival measurements thereof. A data processor, coupled to the baseband signal processor and with input from an auxiliary sensor and a digital database, first calibrates time offsets of said transmitters relative to the BDT receiver's time base and then operates on offset-adjusted time of arrival measurements to produce a position solution.

Abstract: A system is disclosed that enables the estimation of the location of a wireless terminal in a wireless network. The illustrative embodiment works without requiring modifications to be made to the wireless terminal. Furthermore, the hardware of some embodiments of the present invention can be inexpensively deployed indoors. Some embodiments of the present invention are, therefore, ideally suited for use with legacy indoor systems. The system of the illustrative embodiment of the present invention, in some embodiments, uses an offline process and an online process for location estimation. The described system, however, can be used with other techniques for location estimation.

Abstract: In a local positioning system, augmentation of the land-based system is provided by receiving signals from a GNSS. The signals from the land-based positioning system have a code phase accuracy better than one wavelength of a carrier of the signals from the GNSS. Different decorrelation may be used for signals from a satellite than from a land-based transmitter, such as using a digital decorrelator for signals from the satellite and an analog decorrelator for signals from a land-based transmitter. The receivers may include both a GNSS antenna and a local antenna. The phase centers of the two antennas are within one wavelength of the GNSS signals from each other. The local antenna is sized for operation in the X or ISM-bands of frequencies. The GNSS antenna is a patch antenna where the microwave antenna extends away from the patch antenna in at least one dimension.

Abstract: To provide sub-meter accuracy in a local positioning system, ranging signals with a high modulation rate of code, such as 30 MHz, or more are transmitted. Code phase measurements may be used to obtain the accuracy without requiring relative motion or real time kinematic processing. The ISM or X-band is used for the carrier of the code to provide sufficient bandwidth within available spectrums. The length of codes used is less than or about a longest length across the region of operation, such as less than 15 kilometers in an open pit mine. The spread spectrum codes from different land-based transmitters are transmitted in time slots pursuant to a time division multiple access scheme for an increase in dynamic range. To avoid overlapping of code from different transmitters, each time slot includes or is separated by a blanking period. The blanking period is selected to allow the transmitted signal to traverse a region of operation.

Abstract: A system for tracking persons and other objects in a structure in which a plurality of low power transmitter beacons send identifiers to any receiver within range of the beacons. The beacons are attached to the building at known locations that are used as reference points. The person or object carrying the receiver then uses the information of those beacons to determine the location in the structure of the receiver. The data can be sent to a command center or other monitoring location or it can be processed on site by the receiver.

Abstract: To provide a positioning system, a positioning method, and a positioning server, which are capable of improving accuracy in detection of a position. In a positioning system, three or more access points connected to a terminal station by wireless communication are connected to a positioning server through a network, the access points transmit, to the positioning server, information regarding times of having received a signal transmitted from any one of the access points or the terminal station, and the positioning server measures a position of the terminal station based on the information regarding the times, the information having been received from the access points.

Abstract: Apparatus to determine the position of a user terminal, the apparatus having corresponding methods and computer-readable media, comprises a receiver to receive, at the user terminal, a wireless orthogonal frequency-division multiplexing (OFDM) signal comprising a scattered pilot signal; and a processor to determine a pseudo-range based on the scattered pilot signal; wherein a position of the user terminal is determined based on the pseudo-range and a location of a transmitter of the OFDM signal.

Abstract: A self locating device that uses GSM signals associated with GSM digital telephone base stations to determine its current location. The device uses GSM common channel signals to determine observed time differences between a local base station and at least two additional base stations. It also uses the common channel signals to identify these base stations and to match the identifications to geographical locations. It further uses a geolocation algorithm to determine the location of the device relative to the base stations, and uses the geographic location data to determine the current geographic location of the device.

Abstract: Methods and apparatus are described for a navigation system. A process includes providing a plurality of transmitters distributed throughout a desired coverage area; locking the plurality of transmitters to a common timing reference; transmitting a signal from each of the plurality of transmitters. An apparatus includes a plurality of transmitters distributed throughout a desired coverage area; wherein each of the plurality of transmitters comprises a packet generator; and wherein the plurality of transmitters are locked to a common timing reference.

Abstract: To provide sub-meter accuracy in a local positioning system, ranging signals with a high modulation rate of code, such as 30 MHz, or more are transmitted. Code phase measurements may be used to obtain the accuracy without requiring relative motion or real time kinematic processing. The ISM or X-band is used for the carrier of the code to provide sufficient bandwidth within available spectrums. The length of codes used is less than or about a longest length across the region of operation, such as less than 15 kilometers in an open pit mine. The spread spectrum codes from different land-based transmitters are transmitted in time slots pursuant to a time division multiple access scheme for an increase in dynamic range. To avoid overlapping of code from different transmitters, each time slot includes or is separated by a blanking period. The blanking period is selected to allow the transmitted signal to traverse a region of operation.

Abstract: A telecommunications system comprises a first transmitter unit situated at a first, known location; a second transmitter unit situated at a second, unknown location; a first receiving unit at a third, known location arranged to receive signals from the first and second transmitter units; and a second receiving unit at a fourth, known location arranged to receive signals from the first and second transmitter units, wherein the said signals received by the first and second receiving units are usable to ascertain the location of the second transmitter unit.

Abstract: In a local positioning system, the land-based transmitters include free running oscillators or oscillators free of clock synchronization with any remote oscillator. A reference receiver receives the ranging signals from different transmitters and generates timing offset information, such as code phase measurements. The timing offset information is then communicated back to transmitters. The temporal offset information indicates relative timing or phasing of the different transmitted ranging signals to the reference receiver. The transmitters then transmit the temporal offset information with the ranging signals, such as modulating the transmitted code by the timing offset information. A mobile receiver is operable to receive the ranging signals and timing offset information in a same communications path, such as on a same carrier. Position is determined with the temporal offset information and the ranging signals.

Abstract: A method of determining a location is provided. The method comprises placing a plurality of radio frequency (RF) tags within an area, mapping the placement of the plurality of RF tags within the area, detecting one or more of the plurality of RF tags in the area, and determining a location based in part on the mapping and on probability distributions associated with each of the one or more detected RF tags.

Abstract: To provide sub-meter accuracy in a local positioning system, ranging signals with a high modulation rate of code, such as 30 MHz, or more are transmitted. Code phase measurements may be used to obtain the accuracy without requiring relative motion or real time kinematic processing. The ISM or X-band is used for the carrier of the code to provide sufficient bandwidth within available spectrums. The length of codes used is less than or about a longest length across the region of operation, such as less than 15 kilometers in an open pit mine. The spread spectrum codes from different land-based transmitters are transmitted in time slots pursuant to a time division multiple access scheme for an increase in dynamic range. To avoid overlapping of code from different transmitters, each time slot includes or is separated by a blanking period. The blanking period is selected to allow the transmitted signal to traverse a region of operation.

Abstract: In a local positioning system, the land-based transmitters include free running oscillators or oscillators free of clock synchronization with any remote oscillator. A reference receiver receives the ranging signals from different transmitters and generates timing offset information, such as code phase measurements. The timing offset information is then communicated back to transmitters. The temporal offset information indicates relative timing or phasing of the different transmitted ranging signals to the reference receiver. The transmitters then transmit the temporal offset information with the ranging signals, such as modulating the transmitted code by the timing offset information. A mobile receiver is operable to receive the ranging signals and timing offset information in a same communications path, such as on a same carrier. Position is determined with the temporal offset information and the ranging signals.

Abstract: A precise positioning method and system is disclosed for allowing an array of ground transmitters to self-survey their relative location at centimeter-level accuracy by transmitting, amongst the ground transmitters in the array, bi-directional ranging signals associated with a wideband code modulation with a chipping rate faster than 30 MHz.

Abstract: A device and method are provided for estimating a position of a target device (e.g., a device emitting radio frequency energy) based on data pertaining to strength of an emission received from the target device. At a mobile device, emissions are received from the target device when the mobile device is at each of a plurality of positions to produce receive signal strength data representative thereof. The mobile device, also recieves signals from each of a plurality of reference devices at a corresponding known position when the mobile device is at each of the plurality of positions. The position of the target device is estimated based on receive signal strength data associated with received emissions from the target device and from the reference devices. Using the estimated position and estimated transmit power of the target device, a zone of impact of the target device is determined with respect to other wireless activity based on the estimated position and estimated transmit power of the target device.