A METHOD FOR SPATIALLY-ACCURATE LOCATION OF A DEVICE USING AUDIO-VISUAL INFORMATION

摘要

A system to determine positions of mobile computing devices and provide direction information includes a first mobile computing device configured to broadcast a first chirp signal, a second mobile computing device configured to broadcast a second chirp signal indicating receipt of the first chirp signal and a first time information about when the first chirp signal is received, and a third mobile computing device configured broadcast a third chirp signal indicating (a) receipt of the first and second chirp signals and (b) a second time information about when the first and second chirp signals are received. The first mobile computing device is configured to use the first and second time information to determine a position of the second mobile computing device. The first mobile computing device is also configured to transmit text messages to the second mobile computing device to direct a user of the second mobile computing device to a position of a user of the first mobile computing device.