A tracking system includes a first device and a second device. The first device includes plural ultrasonic sources and an inertial measurement unit configured to detect inertial data. The second device includes at least one ultrasonic receiver and a processor. The processor is configured to receive the inertial data, estimate an orientation of the first device according to the received inertial data, determine a first ultrasonic transmitter from the ultrasonic transmitters according to the orientation of the first device and a location of the first device, and send an enablement command about the first ultrasonic transmitter to the first device. The enabled transmitter of the ultrasonic transmitters sends ultrasounds according to the enablement command, the at least one ultrasonic receiver is configured to receive the ultrasounds from the first ultrasonic transmitter, and the processor determines the location of the first device according to the received ultrasounds.

Methods and apparatus for interacting with a tag in a wireless communications area. A user interface is generated with a digital representation of energy levels received into an energy receiving sensor, such as a CCD. The user interface includes interactive portions based upon positions of tags in a wireless communication area. A controller may determine that a Smart Device is associated with access rights to digital content associated with the tag, and the digital content may be displayed in the user interface on the Smart device.

Firearm discharge location systems and associated methods are described. According to one aspect, a firearm discharge location system includes a plurality of microphone devices individually configured to receive acoustic signals of a firearm discharge and to generate information regarding the received acoustic signals of the firearm discharge, a locator system configured to identify a plurality of locations of the microphone devices during the generation of the information regarding the received acoustic signals of the firearm discharge by the microphone devices, and processing circuitry configured to use the identified locations of the microphone devices and the information regarding the received acoustic signals of the firearm discharge to identify the location of the firearm discharge.

Apparatus and methods for enhanced wireless determination of a position and direction of a smart device. Wireless transceivers controlled by the smart device communicate with reference point transceivers to generate data sufficient to determine relative positions of the wireless transceivers and a direction of interest. Operation of one or both of a magnetic force sensor and LIDAR may be operative to verify the position and direction of the Smart Device.

A method of determining a range between two devices, which can for instance be wireless devices, such as handheld devices. The method performs a double-sided two-way ranging protocol at the two devices. This protocol causes the two devices to transmit and receive signals, with a view to determining the range between the two devices, using a two-way ranging methods, where each of the signals is a composite tone generated as a composition of two waveforms that are timewise separated by a gap to form a bipolar waveform. The gap is a zero or low-amplitude signal, contrasting with the two waveforms. The particular pattern in the correlation footprint eases the determination of the time of flight. The method can be used to measure social distancing.

A method of determining a range between two devices, which can for instance be wireless devices, such as handheld devices. The method performs a double-sided two-way ranging protocol at the two devices. This protocol causes the two devices to transmit and receive signals, with a view to determining the range between the two devices, using a two-way ranging methods, where each of the signals is a composite tone generated as a composition of two waveforms that are timewise separated by a gap to form a bipolar waveform. The gap is a zero or low-amplitude signal, contrasting with the two waveforms. The particular pattern in the correlation footprint eases the determination of the time of flight. The method can be used to measure social distancing.

A method includes communicating first and second signals between a first node and a second node, where the first signal includes a sonic signal and the second signal includes an electromagnetic signal. The method also includes using the electromagnetic signal to one of start or stop a timer and using the sonic signal to another of stop or start the timer. The method further includes identifying a one-way time-of-flight associated with the sonic signal traveling between the first and second nodes using the timer. The one-way time-of-flight associated with the sonic signal is indicative of a distance between the nodes.

An acoustic location determination system is disclosed. The system includes one or more transmitting devices and one or more mobile devices. The transmitting device includes a first transducer configured to transmit first acoustic signals having a first frequency, and a second transducer configured to transmit second acoustic signals having a second frequency. The transmitting device further includes a beacon device configured to transmit beacon data via a short-range wireless communication technique. The transmitting device further includes one or more control devices configured to select the first or second acoustic signals based at least in part on one or more operating capabilities of one or more mobile units associated with the real-time locating system. The one or more control devices are further configured to cause transmission of the selected acoustic signals and the beacon data.

An acoustic location determination system is disclosed. The system includes one or more transmitting devices and one or more mobile devices. The transmitting device includes a first transducer configured to transmit first acoustic signals having a first frequency, and a second transducer configured to transmit second acoustic signals having a second frequency. The transmitting device further includes a beacon device configured to transmit beacon data via a short-range wireless communication technique. The transmitting device further includes one or more control devices configured to select the first or second acoustic signals based at least in part on one or more operating capabilities of one or more mobile units associated with the real-time locating system. The one or more control devices are further configured to cause transmission of the selected acoustic signals and the beacon data.

An unmanned underwater vehicle (UUV) is equipped with a GPS, heading sensor, depth and altitude sensors, and an acoustic navigation system. The UUV is deployed in the vicinity of the target location and releases an acoustic transponder (beacon). Using the acoustic navigation system with the GPS reference, the UUV conducts a survey to determine the horizontal location of the beacon on the seafloor and calculates a relative position between the beacon and the target. The UUV can plan a travel path allowing it to relocate the target, using the beacon as a navigation aid. The UUV can submerge to target depth and search for the target using a forward looking sensor. Once the target is acquired on the sensor, the UUV can home to the target.