A transmitting STA can transmit a sensing initiation frame to a first receiving STA in a wireless local area network (wireless LAN) system. The sensing initiation frame can include information related to an STA for transmitting a sounding frame and a session identifier (ID) related to an STA group that is to perform sensing. The transmitting STA can transmit the sounding frame to the first receiving STA. The transmitting STA can receive a first feedback frame for the sounding frame from the first receiving STA. The sounding frame can be a frame transmitted to identify a target. The first feedback frame can include information about a channel changed by means of the target. The sounding frame can include a null data packet announcement (NDPA) frame and a null data packet (NDP) frame.

Determining when an estimated altitude of a mobile device can be used for calibration or location determination. Particular systems and methods determine an area in which the mobile device is expected to reside, determine an altitude value of each section of a plurality of sections in the area, determine if the altitude values meet a threshold condition, and determine that the estimated altitude of the mobile device can be used for determining the position of the mobile device or for calibrating a pressure sensor of the mobile device when the altitude values meet the threshold condition.

A first UE includes: a transceiver; a memory; and a processor, communicatively coupled to the transceiver and the memory, configured to: at least one of: initiate a first UE-to-UE positioning function in response to receiving a first UE-to-UE positioning trigger from a second UE via the transceiver; or send a second UE-to-UE positioning trigger for the second UE via the transceiver to cause the second UE to initiate a second UE-to-UE positioning function; or communicate with the second UE via the transceiver to determine a characteristic of a UE-to-UE location reference signal to be exchanged between the first UE and the second UE; and exchange the UE-to-UE location reference signal with the second UE via the transceiver.

Positioning of a UE is supported in a Radio Resource Control (RRC) Inactive state. The UE receives from a location server a request for periodic or triggered location and an indication of whether uplink, downlink, or uplink and downlink positioning will be used for subsequent location reporting events when the UE is in the RRC Inactive state. When an event is detected, the UE sends a first event report and a second event report to the location server to report the event and enable UE location while the UE is in the RRC Inactive state. The event reports are each sent with Small Data Transmission (SDT). The first event report may include a Request Assistance Data message indicating a request for an uplink (UL) Positioning Reference Signal (PRS) configuration and the second event report may include location measurement performed by the UE.

In one aspect of the present disclosure, an apparatus for locating a mobile railway asset is provided that includes a power source, GNSS circuitry configured to utilize electrical power from the power source to receive GNSS data, and a controller operatively coupled to the power source and the GNSS circuitry. The controller has a power saving mode wherein the controller inhibits the GNSS circuitry from receiving GNSS data and a standard accuracy mode wherein the controller permits the GNSS circuitry to receive GNSS data for a first time period. The controller has a higher accuracy mode wherein the controller permits the GNSS circuitry to receive GNSS data for a second time period longer than the first time period, and subsequently across multiple instances, in order to collect more GNSS data that can be qualified, filtered, sorted, and averaged to produce a more accurate result.

An indoor positioning method based on image visual features. A Wi-Fi signal strength value of a Wi-Fi tag closest to a current location of a mobile device is matched with a signal strength list in a map database to obtain a first location of a first Wi-Fi tag with the greatest matching degree. A SURF descriptor of an image of the Wi-Fi tag closest to the current location of the mobile device is matched with SURF descriptors recorded in the signal strength list in the map database to discover an image of a Wi-Fi tag with the greatest matching degree, thereby obtaining a second location of a second Wi-Fi tag corresponding to the image of the Wi-Fi tag with the greatest matching degree. A three location of a three Wi-Fi tag is obtained according to a homography matrix corresponding to the image of the Wi-Fi tag with the largest matching degree and an empirical value of a positioning error. Positioning information of the mobile device is obtained according to the first location, the second location and the third location.

A system and method for tracking actions of mobile assets used to perform a process within a facility includes a plurality of object trackers positioned throughout the facility to monitor, detect and digitize locations and actions, including movement, of a mobile asset within the facility. The mobile asset includes an identifier which is detectable by each object tracker to track the movement and location of the detected asset in real time. Each object tracker includes at least one sensor for monitoring and detecting the asset and its identifier, where the input sensed by the sensor is transmitted to a computer within the object tracker for time stamping with a detected time, and processing of the sensor input using one or more algorithms to identify the asset type associated with the detected identifier, and the asset's location in the facility at the detected time.

A method for position determining includes: sending a first ranging request to a base station, wherein the first ranging request carries an identifier associated with a second UE, in which the first ranging request is at least associated with ranging between the base station and the second UE; and receiving first range information associated with the first range request from the base station.

Embodiments of the present disclosure provide a positioning system and positioning method. A reverse calibrator for respectively calibrating relative coordinates of at least three ultrasound generators; a processor for generating a carrier signal, multiplying the carrier signal with a spread spectrum pseudo random code to obtain ranging signal, controlling each ultrasound generator to emit ranging signal, and extracting acoustic characteristic parameter of the ranging signals; a device being positioned for capturing ranging signals emitted by each generator, extracting acoustic characteristic parameter of each of the captured ranging signals; determining an ultrasonic delay time of each ultrasonic ranging signal; calculating relative coordinates of the device.

Embodiments of the present disclosure provide a positioning system and positioning method. A reverse calibrator for respectively calibrating relative coordinates of at least three ultrasound generators; a processor for generating a carrier signal, multiplying the carrier signal with a spread spectrum pseudo random code to obtain ranging signal, controlling each ultrasound generator to emit ranging signal, and extracting acoustic characteristic parameter of the ranging signals; a device being positioned for capturing ranging signals emitted by each generator, extracting acoustic characteristic parameter of each of the captured ranging signals; determining an ultrasonic delay time of each ultrasonic ranging signal; calculating relative coordinates of the device.