Estimating the location of a wireless terminal based on the lighting and acoustics in the vicinity of the wireless terminal

摘要

A technique is disclosed for estimating the location of a wireless terminal at an unknown location in a geographic region. The technique is based on a two-part recognition, the first part being that there are certain optical and acoustic characteristics that are present in some environments while not being present in others, such as lighting flicker and sound reverberation. The second part of the recognition is that a correlation exists between the presence of flicker and reverberation in the vicinity of a wireless terminal and whether the wireless terminal is indoors or not. Under certain environmental conditions, flicker and reverberation are often present indoors but not outdoors. By accounting for flicker and reverberation being detected or not being detected in the vicinity of the wireless terminal, the disclosed technique is able to estimate whether the wireless terminal is indoors, which the technique also uses to improve the location estimate.

主权项

1. A method of estimating the probability that a wireless terminal is indoors, the method comprising:
generating, by the wireless terminal and as a consequence of the wireless terminal's normal operation, sound; measuring, by the wireless terminal, a sample of sound in the vicinity of the wireless terminal, wherein at least a portion of the generated sound is the sound that is measured by the wireless terminal; generating, by the wireless terminal, a characterization of reverberation in the vicinity of the wireless terminal based on the sample of sound in the vicinity of the wireless terminal; measuring, by the wireless terminal, a sample of light in the vicinity of the wireless terminal; generating, by the wireless terminal, a characterization of flicker in the vicinity of the wireless terminal based on the sample of light in the vicinity of the wireless terminal; and generating, by the wireless terminal, an estimate of the probability that the wireless terminal is indoors based on: (i) the characterization of reverberation in the vicinity of the wireless terminal; and (ii) the characterization of flicker in the vicinity of the wireless terminal.