Abstract: An example method includes receiving environmental data from a plurality of receivers; calculating, using a processor, an environmental offset based on the environmental data, wherein the environmental offset is operable to adjust a reference phase offset; and dynamically adjusting the environmental offset in response to a detected change in the environmental data.

Abstract: An disclosed method includes receiving, from receivers, TOA data associated with location tag transmissions; determining a first set of the receivers based on the received TOA data; calculating a first tag location estimate for the first set of the receivers by applying a minimizing function to a first set of the TOA data corresponding to the first set of the receivers; determining a first data quality indicator (DQI) for the first tag location estimate; and when the first DQI for the first tag location estimate does not meet a threshold: determining, for the first set of the TOA data, impacts of respective delays on the minimizing function; determining, based on the impacts of the respective delays on the minimizing function, a second set the receivers different from the first set of the receivers; and calculating a second tag location estimate for the second set of the receivers.

Abstract: Methods and apparatus for generating site health information are disclosed herein. An example apparatus is configured to generate a hub quality matrix, wherein the apparatus comprises a processor and memory including machine-readable instructions that, when executed, cause the processor to generate the hub quality matrix using at least two values of a data quality value based on the received location data, a receiver health value based on a receive rate of respective ones of the receivers, a locate gap value based on amounts of time between location estimations, a locate rate value based on a ratio of a first amount of the location estimations and a second amount of tracked participants at the site, and to output the hub quality matrix.

Abstract: An example method includes receiving environmental data from a plurality of receivers; calculating, using a processor, an environmental offset based on the environmental data, wherein the environmental offset is operable to adjust a reference phase offset; and dynamically adjusting the environmental offset in response to a detected change in the environmental data.

Abstract: Systems, methods, apparatuses, and computer readable media are disclosed for associating a radio frequency identification tag with a participant. In one embodiment, a method is provided for associating an unassociated RF location tag with a participant. The method may include determining an unassociated RF location tag to be associated with the participant, receiving sensor derived data from one or more sensors, determining an identity of the particular participant using the sensor derived data, and associating the identity of the particular participant with the unassociated RF location tag.

Abstract: Methods and apparatus for generating site health information are disclosed herein. An example apparatus is configured to generate a hub quality matrix, wherein the apparatus comprises a processor and memory including machine-readable instructions that, when executed, cause the processor to generate the hub quality matrix using at least two values of a data quality value based on the received location data, a receiver health value based on a receive rate of respective ones of the receivers, a locate gap value based on amounts of time between location estimations, a locate rate value based on a ratio of a first amount of the location estimations and a second amount of tracked participants at the site, and to output the hub quality matrix.

Abstract: An disclosed method includes receiving, from receivers, TOA data associated with location tag transmissions; determining a first set of the receivers based on the received TOA data; calculating a first tag location estimate for the first set of the receivers by applying a minimizing function to a first set of the TOA data corresponding to the first set of the receivers; determining a first data quality indicator (DQI) for the first tag location estimate; and when the first DQI for the first tag location estimate does not meet a threshold: determining, for the first set of the TOA data, impacts of respective delays on the minimizing function; determining, based on the impacts of the respective delays on the minimizing function, a second set the receivers different from the first set of the receivers; and calculating a second tag location estimate for the second set of the receivers.

Abstract: Systems, methods, apparatuses, and computer readable media are disclosed for improving, in some examples, reference in a location system. In one embodiment, a method is provided comprising: receiving reference tag blink data from a plurality of receivers; calculating, using a processor, a reference phase offset between the plurality of receivers; and generating a suspended reference phase offset table, wherein a suspended reference phase offset table is generated by causing the reference phase offset to be stored in a memory for later tag location calculations.

Abstract: A disclosed example apparatus receives a tag transmission signal from a tag at a receiver, wherein the tag transmission signal comprises a series of pulses; determines a coarse estimate of a time-of-arrival (TOA) of the tag transmission signal based on a detection of a pulse of the series of pulses in an adjustable coarse timing window, wherein the coarse estimate is based on a plurality of coarse timing windows; determines a fine estimate of the TOA based on a detection of the pulse in at least one of a parallel set of fine timing windows; and determines a sub-window resolution of the TOA based on at least one detection transition between consecutive fine receiver windows of at least one of a plurality of pulses and a weighted average of the TOA for each pulse of the series of pulses.

Abstract: The present invention provides methods for an active RFID tag target location system that provides for an iterative recalculating of a target location estimate by successively testing receiver TOA and DTOA error measurements and discarding outlier receivers. The present invention works to reduce the erratic effects that multipath channel interference and random noise play in target location systems due to incorrect identification of the main pulse of the transmit signal. In addition to providing for a greater accuracy and consistency in a TOA-based target location system, the method also provides for an opportunity to reduce a transmission bandwidth associate with the TOA transmission by the multiple receivers. The method may be considered a post-processing element, as the determination of TOA and DTOA may require a real-time calculation, where the timing constraints for the ensuing target location estimate may be less severe.

Abstract: Methods and apparatus for generating site health information are disclosed herein. An example apparatus configured to receive location data generated based on blink data transmitted by tags and received by receivers deployed at a site includes a processor; and memory including machine-readable instructions that, when executed, cause the processor to: generate a data quality value based on the received location data; generate a receiver health value based on a receive rate of respective ones of the receivers; generate a locate gap value based on amounts of time between location estimations; generate a locate rate based on a ratio of a first amount of the location estimations and a second amount of tracked participants at the site; and generate site health value by combining two or more of the data quality value, the receiver health value, the locate gap value, and the locate rate value; and outputting the site health value.

Abstract: An example disclosed method includes generating, by a microcontroller of a controller, a data packet; and causing the transmission of the data packet on blink data pulses from two or more individual transmit modules, wherein each individual transmit module is in comprises an antenna and a pulse generator configured to transmit the data packet and is in data communications with the controller, wherein the controller causes substantially simultaneous transmission of the blink data pulses from the respective transmit modules to encourage reliable receipt of the blink data pulses at one or more of a plurality of receivers.

Abstract: An example disclosed method includes defining a first zone within a monitored area, a first group of receivers covering the first zone; defining a second zone within the monitored area, a second group of receivers covering the second zone; determining, via a processor, a first position of a first tag based on timing measurements obtained via the first group of receivers; determining, via the processor, whether the first position indicates that the first tag is within the first zone; and when the first position indicates that the first tag is not within the first zone, not reporting data associated with the first tag.

Abstract: Methods and apparatus for generating site health information are disclosed herein. An example apparatus configured to receive location data generated based on blink data transmitted by tags and received by receivers deployed at a site includes a processor; and memory including machine-readable instructions that, when executed, cause the processor to: generate a data quality value based on the received location data; generate a receiver health value based on a receive rate of respective ones of the receivers; generate a locate gap value based on amounts of time between location estimations; generate a locate rate based on a ratio of a first amount of the location estimations and a second amount of tracked participants at the site; and generate site health value by combining two or more of the data quality value, the receiver health value, the locate gap value, and the locate rate value; and outputting the site health value.

Abstract: Systems, methods, apparatuses, and computer readable media are disclosed for providing variable blink rate ultra-wideband (UWB) communications. Some embodiments may provide for a radio frequency (RF) tag including a motion sensor, processing circuitry, and a UWB transmitter. The motion sensor may be configured to generate one or more motion data values indicating motion of the RF tag. The UWB transmitter may be configured to transmit blink data at variable blink rates. The processing circuitry may be configured to receive the one or more motion data values from the motion sensor, determine a blink rate for the UWB transmitter based on the one or more motion data values, and control the UWB transmitter to wirelessly transmit the blink data at the blink rate. In some embodiments, the RF tag may include a UWB receiver and the blink rate may be controlled remotely by a system.

Abstract: Systems, methods, apparatuses, and computer readable media are disclosed for providing variable blink rate ultra-wideband (UWB) communications. Some embodiments may provide for a radio frequency (RF) tag including a motion sensor, processing circuitry, and a UWB transmitter. The motion sensor may be configured to generate one or more motion data values indicating motion of the RF tag. The UWB transmitter may be configured to transmit blink data at variable blink rates. The processing circuitry may be configured to receive the one or more motion data values from the motion sensor, determine a blink rate for the UWB transmitter based on the one or more motion data values, and control the UWB transmitter to wirelessly transmit the blink data at the blink rate. In some embodiments, the RF tag may include a UWB receiver and the blink rate may be controlled remotely by a system.

Abstract: A disclosed example apparatus receives a tag transmission signal from a tag at a receiver, wherein the tag transmission signal comprises a series of pulses; determines a coarse estimate of a time-of-arrival (TOA) of the tag transmission signal based on a detection of a pulse of the series of pulses in an adjustable coarse timing window, wherein the coarse estimate is based on a plurality of coarse timing windows; determines a fine estimate of the TOA based on a detection of the pulse in at least one of a parallel set of fine timing windows; and determines a sub-window resolution of the TOA based on at least one detection transition between consecutive fine receiver windows of at least one of a plurality of pulses and a weighted average of the TOA for each pulse of the series of pulses.

Abstract: The present invention provides methods for a high-resolution active RTLS tag location determination system that provides for <1 ns TOA accuracy and resolution and significantly reduces the channel effects of multipath interference, even in low SNR applications. To accomplish these objectives, the present invention provides for an iterative and adaptive windowing function in each of the receivers of a receiver grid that captures multiple reflections of multiple transmissions from each of the associated target RTLS tags. The adaptive windowing function is used in conjunction with an asynchronous transmit and receive clock function that effectively increases resolution of TOA detection to levels less than the minimum detection window width associated with each of the receivers in the receiver grid.

Abstract: An example disclosed method includes generating, by a microcontroller of a controller, a data packet; and causing the transmission of the data packet on blink data pulses from two or more individual transmit modules, wherein each individual transmit module is in comprises an antenna and a pulse generator configured to transmit the data packet and is in data communications with the controller, wherein the controller causes substantially simultaneous transmission of the blink data pulses from the respective transmit modules to encourage reliable receipt of the blink data pulses at one or more of a plurality of receivers.

Abstract: Systems, methods, apparatuses, and computer readable media are disclosed for associating a radio frequency identification tag with a participant. In one embodiment, a method is provided for associating an unassociated RF location tag with a participant. The method may include determining an unassociated RF location tag to be associated with the participant, receiving sensor derived data from one or more sensors, determining an identity of the particular participant using the sensor derived data, and associating the identity of the particular participant with the unassociated RF location tag.