A method and system for using GPS signals and a magnetic field to track an underground magnetic field source. A tracker having an antenna for detecting the magnetic field and a GPS receiver is coupled to a processor. The magnetic field is used by the antenna to direct the tracker to a field null point. Once multiple measurements of the field are taken, the changes in signal strength as the absolute position of the tracker is changed, are used to determine whether the closest field null point is in front of or behind the underground beacon. The position and depth of the beacon can then be estimated.

Method, node, computer program, and computer program product in a wireless communication network, comprising a network communication unit with a medium access control layer (MAC-Layer), said node configured to calculate the Time of Arrival and/or Time of Flight based on a counted time from transmission of a response request message in the medium access control layer of said node to the corresponding arrival of a response to said response request message in the medium access control layer (MAC-Layer) of said node.

Disclosed are devices, systems and methods for combining observations obtained at two different mobile devices attached to a human user for performing a navigation operation. For example, observations of a signal acquired at a first mobile device may be selected for computing a position fix based, at least in part, on a utility indicator associated with the observations.

A system comprising a mobile computing device that includes a processor and a memory. The memory storing programming executable by the processor to detect an identifier in each of two or more of asynchronous light sources detected by a light sensor, the identifier including a position of the light source and use at least a coordinate system having an origin in the light sensor and the position of the light source, to determine a location of the mobile device.

An identification system includes an identification device and a communication device. The identification device is attached to an article and including a sensor. The identification device is configured to operate in a plurality of modes and configured to switch between modes of the plurality of modes based on one or more conditions of a surrounding environment sensed by the sensor. The identification device is configured to send data to a server. The communication device of a user of the identification system is configured to receive data including location data of the identification device from the server using short message service protocols or messages through a signaling channel.

An identification system includes an identification device and a communication device. The identification device is attached to an article and including a sensor. The identification device is configured to operate in a plurality of modes and configured to switch between modes of the plurality of modes based on one or more conditions of a surrounding environment sensed by the sensor. The identification device is configured to send data to a server. The communication device of a user of the identification system is configured to receive data including location data of the identification device from the server using short message service protocols or messages through a signaling channel.

Systems and methods for calibrating a distance model and estimating a distance between one or more wireless devices, such as one or more Bluetooth or other types of wireless devices, for social distancing and contact tracing are described. The system includes at least one processor configured to determine an environmental fingerprint from an acoustic signal propagating within an environment, such as a room or another area. The environmental fingerprint may be compared to a database of predefined environmental fingerprints and one or more similar predefined environmental fingerprints identified. The predefined environmental fingerprints may be associated with one or more distance model parameters, which may be used to calibrate a distance model. In addition, the predefined environmental fingerprints may be associated with pretrained distance models. The calibrated or pretrained distance models may be used to process wireless signals in the environment to estimate the distance between users of wireless devices.

Determining the physical location of wirelessly connected devices within a network can provide a number of security benefits. However, manually determining and configuring the physical location of each device within a system can be burdensome. To ease this burden, devices within a network are equipped with a location detection sensor that is capable of automatically determining a device's location in relation to other devices within the network. A location detection sensor (sensor) may include a light source, a light direction sensor, a rangefinder, and a radio or wireless network interface. Two location detection sensors can perform a location detection process to determine their relative locations to each other, such as the distance between them. As more sensors are added to a network, a sensor management system uses the relative locations determined by the sensors to map the sensors to a physical space layout.

A method, in a mobile device, of controlling region determination by the mobile device, includes: determining a present pressure at the mobile device; determining, based on the present pressure and a reference pressure, that the mobile device moved from a first region to a second region within a structure, the first region and the second region being different regions of the structure and vertically displaced from each other; and performing region determination in response to determining that the mobile device moved from the first region to the second region.

Disclosed are devices, systems and methods for combining observations obtained at two different mobile devices attached to a human user for performing a navigation operation. For example, observations of a signal acquired at a first mobile device may be selected for computing a position fix based, at least in part, on a utility indicator associated with the observations.