The reason why FM receivers are present on smartphones is that they can be used to locate your position by noting a simple thing as signal strength of transmitters. More advanced methods makes use of SNR, frequency deviation and multipath interference characteristics. And the same method can be used for WiFi which of course makes collection of such data very useful for localization purposes where GPS etc isn't useful. Arrival time of a radio signal that is reported to the operator from many devices may also be used for the same purpose.
(Score: 3, Funny) by mcgrew on Thursday May 22 2014, @01:31AM
The basic principles of most things go over most people's heads.
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