Abstract: System and methods of tracking a position of a mobile device with an electromagnetic signal-transmitting antenna include receiving electromagnetic signals from the transmitting antenna of the mobile device by a plurality of receiver antennae of a base station and by one or more receiver antennae of a relay station. The relay station transmits to the base station timing information associated with the electromagnetic signals received by the one or more receiver antennae of the relay station. The base station computes a position of the transmitting antenna of the mobile device based on timing information computed from the electromagnetic signals received by the plurality of receiver antennae of the base station and on the timing information received from the relay station.

Abstract: Position and orientation tracking systems and methods include a transmitting antenna transmitting a radio frequency (RF) signal. At least one receiving antenna acquires the RF signal. One of the at least one receiving antenna and the transmitting antenna is designated a reference antenna. A processing unit determines a phase difference between the RF signal received by each receiving antenna and the reference antenna. The processing unit computes a position of the transmitting antenna with respect to the at least one receiving antenna in response to the phase difference determined for each receiving antenna.

Abstract: A system and method for recovering from a failure during the position tracking of an RF-transmitting device includes tracking the position of the radio frequency (RF) transmitting device based on RF signals emitted by the RF-transmitting device. If the tracking loses the position of the RF-transmitting device, new phase difference data are calculated from the RF signals transmitted by the RF-transmitting device and received at four or more antennas. A subset of candidate position solutions for evaluation is identified based on the new phase difference data. One or more of the candidate position solutions in the subset is evaluated to find an acceptable position solution. The tracking of the position of the RF-transmitting device resumes using the acceptable position solution.

Abstract: Systems and methods for tracking movement of individuals through a building receive, by one or more RF nodes disposed near an entrance to the building, RF signals from RF-transmitting mobile devices carried by persons near the entrance, capture an image of the persons while they are near the entrance, determine an identity and relative distance of each RF-transmitting mobile device from each RF node based on information associated with the RF signals received by that RF node, detect humans in the image, determine a relative depth of each human in the image, and assign the identity of each RF-transmitting mobile device to one of the humans detected in the image based on the relative distance of each RF-transmitting mobile device from each RF node and the relative depth of each human in the image, thereby identifying each individual who to be tracked optically as that individual moves throughout the building.

Abstract: Systems and methods for position tracking include at least three spatially separated radio-frequency (RF) sources of radio signals. Each RF source is disposed in an area at a location known to that RF source. Each RF source includes an RF transmitter configured to transmit radio signals that carry a unique identifier and the known location of that RF source. The position tracking system and method include at least one tag. Each tag is coupled to a different mobile object and includes a radio module with an RF receiver for receiving the radio signals transmitted by the at least three spatially separated RF sources. Each tag further includes memory and a processor that executes executable code stored in the memory to compute a range from that tag to each of the at least three RF sources and to compute a position of that tag based on at least three computed ranges.

Abstract: An RF position tracking system for wirelessly tracking the three-dimensional position of a tracked object. The tracked object has at least one mobile antenna and at least one inertial sensor. The system uses a plurality of base antennas which communicate with the mobile antenna using radio signals. The tracked object also incorporates the inertial sensor to improve position stability by allowing the system to compare position data from radio signals to data provided by the inertial sensor.

Abstract: A system and method for recovering from a failure during the position tracking of an RF-transmitting device includes tracking the position of the radio frequency (RF) transmitting device based on RF signals emitted by the RF-transmitting device. If the tracking loses the position of the RF-transmitting device, new phase difference data are calculated from the RF signals transmitted by the RF-transmitting device and received at four or more antennas. A subset of candidate position solutions for evaluation is identified based on the new phase difference data. One or more of the candidate position solutions in the subset is evaluated to find an acceptable position solution. The tracking of the position of the RF-transmitting device resumes using the acceptable position solution.

Abstract: Vehicles and methods of navigating vehicles comprise at least three receiver antennae configured to receive radio frequency (RF) signals from one or more RF-transmitting antennae coupled to an object, receiver circuitry coupled to the receiver antennae to acquire the RF signals and to determine timing information from the acquired RF signals, memory storing information related to fixed distances between each receiver antenna and each other receiver antenna, a processor configured to determine a relative position of the vehicle with respect to the one or more RF-transmitting antennae based on the stored information related to the fixed distances between each receiver antenna and each other receiver antenna and on the timing information determined by the receiver circuitry, and a control system configured to control operation of the vehicle in response to the relative position of the vehicle with respect to the one or more RF-transmitting antennae determined by the processor.

Abstract: A system includes a wireless device having a radio frequency (RF) receiver, an RF transmitter, and means for producing sensory feedback to a user of the wireless device. A position-tracking system includes at least three antennae. The position-tracking system computes a multi-dimensional position of the wireless device using triangulation or trilateration based on time of arrival information from radio signals transmitted by the RF transmitter of the wireless device and received by each of the at least three antennae. A processor receives the multi-dimensional position of the wireless device determined by the position-tracking system, correlates the multi-dimensional position to a point of interest registered with an interactive software program that produces a virtual reality environment, and generates, in response to the multi-dimensional position correlated with the registered point of interest, data configured to activate the sensory feedback producing means of the wireless device.

Abstract: A position tracking system for tracking a physical location of a radio frequency (RF) transmitter comprises at least four RF receiver antennae at known locations. Each receiver antenna receives RF signals from the RF transmitter. One receiver antenna is used as a reference antenna. A receiver channel unit is in communication with the RF receiver antennae. The receiver channel unit comprises a reference receiver channel and a measurement receiver channel. A multiplexer is dynamically configurable to selectively connect the reference receiver channel to the reference receiver antenna and to connect, in succession, each other receiver antenna to the measurement receiver channel. A comparator measures phase differences between the RF signals received by the reference antenna and those received by each other receiver antennae. A data processor computes the physical location of the RF transmitter from the phase differences measured by the comparator and the known locations of the receiver antennae.

Abstract: Position tracking systems and methods for tracking a physical location of a radio frequency (RF) transmitter include an RF transmitter transmitting an RF signal from a plurality of known locations. At least four RF receiver antennae are disposed at unknown locations within range of the RF transmitter to receive the RF signals transmitted from the plurality of known locations. A receiver station in communication with the at least four RF receiver antennae initially calibrates a relative position of each RF receiver antenna with respect to the other RF receiver antennae based on the plurality of known locations and on information acquired in response to the RF signals received at the at least four RF receiver antennae.

Abstract: Systems and methods improve virtual reality and augmented reality functionality for mobile devices using radio frequency (RF) signals transmitted by a tracked device and received at four or more spatially separated antennae. These antennae are connected, wirelessly or through wired connections, to a base station. Through RF signal time of arrival information acquired at the antennae, the base station can continuously determine accurate position information of the tracked device, without lighting or line of sight limitations experienced by camera and other optical systems. As the position of the RF-transmitting tracked device is registered within a virtual environment produced by an interactive software program in communication with (or part of) the base station, the virtual viewpoint of the tracked device is controlled to reflect the relative position and orientation of the tracked device with respect to the virtual environment produced by the software program and displayed on a view screen.

Abstract: A system and method for recovering from a failure during the position tracking of an RF-transmitting device includes tracking the position of the radio frequency (RF) transmitting device based on RF signals emitted by the RF-transmitting device. If the tracking loses the position of the RF-transmitting device, new phase difference data are calculated from the RF signals transmitted by the RF-transmitting device and received at four or more antennas. A subset of candidate position solutions for evaluation is identified based on the new phase difference data. One or more of the candidate position solutions in the subset is evaluated to find an acceptable position solution. The tracking of the position of the RF-transmitting device resumes using the acceptable position solution.

Abstract: A shelving system has at least one shelf, a camera fixed at a distance from the at least one shelf such that a field of view of the camera faces the at least one shelf and closely encompasses the at least one shelf, and a controller in communication with the camera. The controller has a processor adapted to receive images captured by the camera within the camera's field of view and to determine from the images whether a particular object has been placed on, moved, or removed from the at least one shelf.

Abstract: System and methods of tracking a position of a mobile device with an electromagnetic signal-transmitting antenna include receiving electromagnetic signals from the transmitting antenna of the mobile device by a plurality of receiver antennae of a base station and by one or more receiver antennae of a relay station. The relay station transmits to the base station timing information associated with the electromagnetic signals received by the one or more receiver antennae of the relay station. The base station computes a position of the transmitting antenna of the mobile device based on timing information computed from the electromagnetic signals received by the plurality of receiver antennae of the base station and on the timing information received from the relay station.

Abstract: A system and method for providing immersive interaction between users and interactive software programs comprise receiving radio frequency (RF) signals, transmitted by an RF-transmitting device, at three or more spatially separated antennas. Time of arrival information is acquired from the RF signals. A position of the RF-transmitting device is computed from the time of arrival information acquired from the RF signals. The position of the RF-transmitting device is registered within a virtual environment produced by an interactive software program (which can execute on a mobile device). The virtual environment, as affected by the registered position of the RF-transmitting device, is transmitted to a display apparatus for display.

Abstract: System and methods of tracking a position of a mobile device with an electromagnetic signal-transmitting antenna include receiving electromagnetic signals from the transmitting antenna of the mobile device by a plurality of receiver antennae of a base station and by one or more receiver antennae of a relay station. The relay station transmits to the base station timing information associated with the electromagnetic signals received by the one or more receiver antennae of the relay station. The base station computes a position of the transmitting antenna of the mobile device based on timing information computed from the electromagnetic signals received by the plurality of receiver antennae of the base station and on the timing information received from the relay station.

Abstract: Position and orientation tracking systems and methods include a transmitting antenna transmitting a radio frequency (RF) signal. At least one receiving antenna acquires the RF signal. One of the at least one receiving antenna and the transmitting antenna is designated a reference antenna. A processing unit determines a phase difference between the RF signal received by each receiving antenna and the reference antenna. The processing unit computes a position of the transmitting antenna with respect to the at least one receiving antenna in response to the phase difference determined for each receiving antenna.

Abstract: Tracking systems and methods for obtaining position coordinates of transmitters are provided. One or more transmitters send multiple carrier signals to multiple receivers, where the time difference of arrival of the multiple carrier signals are used to determine the location of each transmitter. Accuracy is obtained by using phase information of multiple carrier frequencies for time difference of arrival measurements. The accuracy obtained by a receiver depends on the quality of the received carrier signal; a received carrier signal may become distorted by the presence of multipath interference. By using multiple signals with different frequencies, the system can screen or compensate for multipath effects. This screening can be accomplished either through various signal-sampling techniques or by averaging the signals received at the receiver. Because signals with different frequencies have different multipath experiences, a computer can analyze and compensate for “good” and “bad” signals.

Abstract: A system includes a wireless device having a radio frequency (RF) receiver, an RF transmitter, and means for producing sensory feedback to a user of the wireless device. A position-tracking system includes at least three antennae. The position-tracking system computes a multi-dimensional position of the wireless device using triangulation or trilateration based on time of arrival information from radio signals transmitted by the RF transmitter of the wireless device and received by each of the at least three antennae. A processor receives the multi-dimensional position of the wireless device determined by the position-tracking system, correlates the multi-dimensional position to a point of interest registered with an interactive software program that produces a virtual reality environment, and generates, in response to the multi-dimensional position correlated with the registered point of interest, data configured to activate the sensory feedback producing means of the wireless device.