Described is an improved active-beacon/passive-listener time difference of arrival navigation system that relies on the multiple beacons to transmit uncoded acoustic pulses of a same frequency that propagate in the system at a same time for high-speed device tracking. Listening devices may receive multiple encoded radio frequency pulses (RF) prior to a single acoustic pulse, and then resolve which RF pulse corresponds to the acoustic pulse using triangulation techniques.

Ultrasonic transmitters periodically transmit ultrasonic ranging signals, and an ultrasonic receiver receives the ultrasonic ranging signals on a mobile device in order to locate the mobile device in a venue. A controller determines a noise level in the venue, and varies a sound level of the periodically ranging signals based on the determined noise level, thereby optimizing the position of the mobile device.

An electronic fish finder transducer lifting system includes a mechanical actuating device; a transducer lifting device; an electronic fish finder attachment member, rotatably connected to the transducer lifting device, configured to attach to an electronic fish finder; and a mechanical linkage, connected to the mechanical actuating device and the transducer lifting device, configured to transfer force, applied to the mechanical actuating device, to the transducer lifting device to lift a front portion of the transducer lifting device.

Systems and methods for ultrasonic collision management in virtual, augmented, and mixed reality (xR) applications are described. In some embodiments, an Information Handling System (IHS) may include a processor and a memory coupled to the processor, the memory having program instructions stored thereon that, upon execution by the processor, cause the IHS to: execute an xR application to display an xR image to a user of the IHS; and detect, via an ultrasonic sensor coupled to the processor, a potential physical interaction between the user and a physical object during execution of the xR application.

A method of generating a representation of a structure includes providing an ad hoc mesh network having at least two nodes associated with the structure, obtaining time of flight data for each node in the network, and using the time of flight data to generate the representation of the structure. A method of generating a three-dimensional representation of a structure includes providing an ad hoc mesh network having at least three nodes associated with the structure, wherein at least one node is a mobile node that moves around the structure, obtaining time of flight data for each pair of nodes in the network, and using the time of flight data to generate the three-dimensional representation of the structure.

An information provision apparatus includes: an information signal generator unit that generates an information signal containing information on a provision target; a converter unit that converts the generated information signal into a sound wave and outputs the sound wave; and a wireless communicator unit that performs wireless transmission and reception of data with a communication apparatus. Further, the information provision apparatus is enabled to receive an activation signal transmitted using a specific wireless transmission medium from a signal output apparatus. In response to that the activation signal is received, the information provision apparatus transitions into a state enabling wireless transmission and reception of data with the communication apparatus.

The present disclosure relates to a location determination system that includes acoustic transmitting devices, location tags, and a wireless mesh network, where the wireless mesh network uses battery-powered devices. A location tag receives acoustic signals (e.g., ultrasound signals) from an acoustic transmitting device. Clocks from members of the wireless mesh network are synchronized by observation of clock pairings, each clock pair formed by respective clocks in a transmitting device that transmits a message and a receiving device that receives the message. By analyzing the observed clock pairings, a best fit between the clock pairings may be determined. After selecting a reference clock, an acoustic transmission schedule may be propagated to the respective acoustic transmitting device.

A method and apparatus for locating a target in a venue is described. A backend controller activates transmitters in a venue to send burst signals using a double symmetry configuration formed of a plurality of separate transmitter groups. The backend controller activates the transmitters into a second, different configuration for bursting. The resulting location signal information from each configuration is obtained by the backend controller, which then more accurately determines the location of the target in the venue.

A range-finding and/or object-positioning system comprises one or more target devices; one or more reference devices communicating with said one or more target devices via one or more wireless signal sets, each wireless signal set comprising at least a first-speed signal having a first transmission speed and a second-speed signal having a second transmission speed, and the first transmission speed being higher than the second transmission speed; and at least one processing unit performing actions for determining at least one distance between one target device and one reference device based on the time difference between the receiving time of the first-speed signal and the receiving time of the second-speed signal of the wireless signal set communicated between said reference and target devices.

A transmitter device transmits an ultrasonic signal encoding a binary identifier. Each bit position in the identifier is associated with a pair of frequencies and with first and second time positions in the signal. The bit value determines which of the pair of frequencies is transmitted at the first time position, with the other being transmitted at the second time position. A receiver device receives the signal. Each bit position of the identifier is decoded based on the strength of the received signal at (a) the first frequency and first time position associated with the particular bit position, (b) the associated first frequency and second time position, (c) the associated second frequency and first time position, and (d) the associated second frequency and second time position. The decoded identifier is used to determine information relating to the position of a mobile one of the devices.