A system and methods are disclosed for synchronizing two or more groups of base stations in a wireless location system. In one embodiment, a first wireless base station belonging to a first group of wireless base stations transmits a first RF beacon for synchronizing the first group of wireless base stations and a second RF beacon that is used to synchronize a second group of wireless base stations. Wireless base stations in the first and second groups transmit respective non-RF (e.g., infrared, ultrasound, etc.) beacons that can be used to locate a portable tag.

A location beacon assembly includes a wrist band that may be worn on a wrist. A beacon unit is coupled to the wrist band. The beacon unit is turned on when the beacon unit is exposed to water. The beacon unit selectively emits blue light. Thus, the beacon unit is visible at a maximum depth in water thereby facilitating a swimmer to be located when the swimmer is drowning. The beacon selectively emits an echolocation sound that has a frequency ranging between 10 kHz and 20 kHz. Thus, the beacon unit is audible at a maximum depth in water thereby facilitating the swimmer to be located when the swimmer is drowning.

Devices, non-transitory computer-readable media and methods for providing a haptic signal based upon a detection of an object are disclosed. For example, the processor of a device may transmit a first ultrasonic signal via an ultrasonic emitter and detect an object based upon a receiving of a reflected signal via an ultrasonic detector, where the reflected signal comprises a reflection of the first ultrasonic signal from the object. The processor may further monitor for a second ultrasonic signal via the ultrasonic detector. The device may be associated with a user, and the second ultrasonic signal may be associated with a teammate of the user. The processor may also select whether to provide an instruction to a haptic actuator when the object is detected, based upon whether the second ultrasonic signal is received via the ultrasonic detector.

A system, method, and computer-readable storage medium to determine a table location of a payment cardholder within a restaurant, to enable automatic bill receipt for the table.

The disclosure relates to a method for requesting and granting priority between a host vehicle and other vehicles, and to a system which implements the method. The host vehicle, through the use of on-board vehicle sensors, detects and identifies an impeding vehicle which interferes with the host vehicle's path. The host vehicle transmits a priority request to the impeding vehicle. The priority request includes a remuneration offer. The impeding vehicle evaluates the priority request, including the sufficiency of the host vehicle's remuneration offer, and grants or denies the host vehicle's priority request. If granted, the impeding vehicle modifies its path to be less impeding to the host vehicle, for example by assuming a cooperative path that lets the host vehicle pass the impeding vehicle.

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.

A method and system for enabling the determination of a position of a receiver within a space includes transmitting a beacon signal from each of a plurality of beacon devices located at different locations within the space. The beacon signal transmitted from each beacon device has a unique information component and may have a unique frequency pattern of multiple frequencies. Each beacon signal can be distinguishable from the beacon signals transmitted from any other of the beacon devices based on the combination of its unique information component and its unique frequency pattern. The beacon signals are received at a receiver. At the receiver, for each beacon signal of a working subset, time-delay information of the received beacon signal is determined and multilateration is applied to determine the position of the receiver based on the location of each beacon device of the working subset.

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.

The present disclosure relates to a location determination system that includes acoustic transmitting devices and mobile devices. A mobile device receives acoustic signals (e.g., ultrasound signals) from an acoustic transmitting device. The mobile device must be able to identify the acoustic transmitting device with particularity when receiving the acoustic signals. It is more efficient to use a short identifier, for example 6 bits, for this purpose because it requires less power to transmit and decode. By utilizing the rotating identifier system described herein, more acoustic transmitting devices can be distinguished than using a time-invariant identifier would otherwise provide, and the transmissions are more secure and therefore less vulnerable to free-riders.

The ultrasonic homing assembly includes a base unit that may be coupled to a boat anchor. A base processor is coupled to the base unit. A transmitter is coupled to the base unit. The transmitter is operationally coupled to the processor. The transmitter transmits a location signal. A remote unit may be worn by a diver. A remote processor is coupled to the remote unit. A receiver is coupled to the remote unit. The receiver is operationally coupled to the remote processor. The receiver receives the location signal from the transmitter. A display is coupled to the remote unit. The display is operationally coupled to the processor. The display directs the diver toward the base unit. The diver swims toward the boat anchor.