Techniques are provided for geolocation of a radar emitting source. A methodology implementing the techniques according to an embodiment includes calculating time difference of arrival (TDOAs) of ground emitter radar pulses, within a dwell period, between two long baseline interferometer (LBI) antennas. The TDOA calculations are based on a precision estimate of the time of arrival of the radar pulses. The method further includes calculating an LBI phase wrap disambiguation factor based on (1) the TDOAs, (2) an average of frequencies of the radar pulses within the dwell period, and (3) an average of phase shifts of the radar pulses between the LBI antennas within the dwell period. The method further includes mapping a curve of points onto the surface of the earth based on an LBI cone angle calculation employing the LBI phase wrap disambiguation factor. The curve of points is associated with a geolocation of the ground emitter.

One embodiment is a method including: receiving signals of at least 4 paths from the Tx UE; measuring a ToA, an AoA, an AoD of each of the signals of 4 paths, determining each distance between the Rx UE and each scatter of each 4 paths, each distance between the Rx UE and the Tx UE and a driving direction of the Tx UE, based on the ToA, AoA and AoD; determining a position of the Tx UE based on results of measurement and results of the determination, wherein an assumption that each of x-axis distance and y-axis distance between the Tx UE and Rx UE based on the AoA, AoD and the driving direction of the Tx UE are identical in signal path 1 and signal path p (p=2, 3, 4) is used for determination of the position.

A method, device and system are disclosed for geo-locating a device. In one embodiment, a first wireless transmitter/receiver pages a second wireless transmitter/receiver to establish a communication. A plurality of packets transmitted by the first wireless transmitter/receiver and transmitted by the second wireless transmitter/receiver are received by a wireless receiver. The reception time of packets transmitted by the first wireless transmitter/receiver and the second wireless transmitter/receiver is recorded. A time delay based at least in part on the recorded reception times of each packet is calculated, and a location of the second wireless device based on the calculated time delay is determined. A target location of the second wireless transmitter/receiver is determined based on a plurality of the determined locations of the second wireless transmitter/receiver.

Systems and methods for determining a physical location of a first Radio Frequency Identification (RFID) tag. The methods involve: analyzing timestamped tag read information acquired during multiple tag reads to determine a first physical location for the first RFID tag read by the mobile reader while moving through a facility; identifying second RFID tags from a plurality of RFID tags read by the mobile reader that are located in proximity to the first RFID tag and that are coupled to objects similar to an object to which the first RFID tag is coupled; selecting an RFID tag from the second RFID tags that has a first location confidence value associated therewith which is greater than second location confidence values associated with other RFID tags of the second RFID tags; and modifying the first physical location based on a second physical location of the RFID tag selected from the second RFID tags.

First information is obtained from a sensing device at a first time. The first information corresponds to a radio signal received at the device from a candidate location. The device is at a first location at the first time. Second information is obtained from the device at a second time. The second information corresponds to a radio signal received at the device from the candidate location. The device is at a second location at the second time. A system determines that a pattern is in each of the first and second information and determines relationships between the candidate location and the device at each first and second location. The system obtains inverses of the relationships and determines estimates of the received radio signals based on the information and inverses. The system measures or estimates energy emitted from the candidate location based on the estimates.

A method using an array of ESM receivers comprises; a step of determining a first locus on the basis of a first measurement giving information on the angle difference of arrival of the emission beam on two receivers, the first locus including the points in space giving the same first measurement on the two receivers; a step of determining a second locus on the basis of a second measurement giving information on the direction of arrival on at least one receiver, the second locus including the points in space giving the same second measurement on the receiver; and a step of determining a third locus on which the position of the source is found, the third locus being the intersection of the first locus and of the second locus.

Techniques are provided for geolocation of an airborne radar emitting source. A methodology implementing the techniques according to an embodiment includes initializing a search grid with hypothesized emitter geolocations boxes of the grid. The method further includes refining geolocations based on calculated pulse repetition intervals of de-Dopplerized times of arrival (TOAs) of emitter pulses received at multiple collection platforms within a dwell period. A residue metric is employed to qualify candidate target geolocations based on differences between the measured TOAs and hypothesized TOAs associated with the refined geolocations. A candidate history tracks the geolocations of the candidates with the smallest residue over subsequent dwells, identifying such candidates that match locations in the history and updating counts of times the candidate has been matched. Candidates with lagging match counts are dropped from the history. The search grid size is reduced to encompass regions surrounding the viable candidates by a selected margin.

A system for locating an object in a volume of space can include a communication device of the object disposed in the volume of space, where the communication device broadcasts a first communication signal into the volume of space, where the first communication signal includes a first identification of the object. The system can also include multiple integrated sensor devices disposed in the volume of space, where each integrated sensor device includes at least one sensor, at least one receiver, and at least one transmitter, where the at least one receiver of a subset of the integrated sensor devices receives the first communication signal, where each of the subset determines a signal strength of the first communication signal. The system can further include at least one access controller that receives at least one second communication signal sent by the subset.

Techniques are provided for geolocation of an airborne radar emitting source. A methodology implementing the techniques according to an embodiment includes initializing a search grid with hypothesized emitter geolocations boxes of the grid. The method further includes refining geolocations based on calculated pulse repetition intervals of de-Dopplerized times of arrival (TOAs) of emitter pulses received at multiple collection platforms within a dwell period. A residue metric is employed to qualify candidate target geolocations based on differences between the measured TOAs and hypothesized TOAs associated with the refined geolocations. A candidate history tracks the geolocations of the candidates with the smallest residue over subsequent dwells, identifying such candidates that match locations in the history and updating counts of times the candidate has been matched. Candidates with lagging match counts are dropped from the history. The search grid size is reduced to encompass regions surrounding the viable candidates by a selected margin.

In the present invention, to make it possible to enhance the accuracy of positioning in an area not reached by a GNSS signal: a first position of a host device is estimated; the error of the first position is estimated; from a second device, other device information is received that includes a second position of the second device and a second error of the second position that have been estimated by the second device; and if the second error is smaller than the first error, the first position and first error are corrected on the basis of the other device information.