Apple is studying the use of ultrasonic telemetry to determine how far apart iPhones are from each other before opening lines of communication.
The Apple AirDrop is a very useful tool for many users, as it is able to quickly transfer files between devices and those belonging to other people. The function generally works within a limited range, which can help limit these transfers to those only in a specific area.
Due to the nature of RF transmissions, it is possible for bad actors to listen to certain elements of communication between people, if they are close enough to receive them. The potentially long range of the signal can also mean that people could try to use it for harmful purposes without being caught, such as reports of unsolicited image transfers to public places in 2017.
One way to avoid this is to correctly ensure that the intended recipient is within a specific range of the transmission device, as it would be possible to control the strength of the transmissions to limit their range if the communication distance can be determined .
In a patent granted Tuesday by the US Patent and Trademark Office entitled “Ultrasound variant for mobile devices”, Apple proposes a mechanism which uses ultrasonic pings to know how far the devices are distant.
The proposed system uses ultrasonic transmitters and receivers on each device, used to send and receive the ultrasonic signals.
It is suggested that two ultrasonic signals can be sent from a single device, which can be received by multiple ultrasonic receivers on the secondary device. By monitoring the time interval of the signals, the receiving device can measure the distance to which the sending device is distant.
Time lapse control could be improved by coding the ultrasonic signal with a timecode for its transmission. By comparing the time code to the actual reception time, the reception device can again determine the duration of the signal path, and therefore the distance.
The patent explains that it would look for unencumbered frequencies before trying position detection by ultrasound.
Time lapse calculation could be further improved with synchronized clocks, Apple suggesting that an electromagnetic transmitter could synchronize with nearby devices. An RF transmitter could also be used to provide more informationon relevant for distance determination, such as frequency bands or communication channels.
Using multiple receivers, the receiving device could even determine the direction from which the ultrasonic signals are coming, for example by comparing the reception time of each receiver for a signal. This can allow each device to create a three-dimensional map of other device positions.
The patent lists its inventors like Brian Michael King, David Amm, Scott P. Porter and Steven P. Hotelling.
Apple files numerous patent applications on a weekly basis, but while the existence of a filing indicates areas of interest to Apple’s research and development teams, it does not guarantee that ideas will appear in the future. product or service.
Current iPhones offer a certain level of range and direction-finding capabilities with the U1 chip, used for ultra broadband communications. Although it can be used to create a secure and fast short-range network, the concepts described in the patent could offer better positioning informationon than Ultra Wideband offerings to application developers.
Ultrasonic positioning is not limited to smartphones only. In a patent application revealed in March, ultrasonic sensors could be used in a VR or AR headset, such as Apple Glass, to provide very precise positioning data that could improve real-world view and digital overlays.
Apple has also explored the possibility of using UWB and ultrasonic communications to improve HomeKit, using technologies to determine the locations of nearby Smarthome devices.