By cross-referencing the satellite data with a ground-based transmitter of precisely known location, the accuracy can be boosted tenfold or more.

ECONOMIST: Global positioning: Accuracy is addictive | The

And, to add another level of complexity, individual phones will adjust their transmitter power based upon the received signal strength from the MicroCell.

FORBES: Some AT&T MicroCell Users Are Experiencing Problems With iPhone 5 and iOS 6

The Recorder III is a hard drive-based unit that will supposedly sport Ethernet and possibly WLAN and an FM transmitter, like the 442v2.

ENGADGET: Neuros to release Recorder III, Neuros III DAC, 442 Version 2

X2Impact, a Seattle-based startup, has embedded accelerometers into mouth guards and linked them to a transmitter in the chin strap, according to Steve Clayton, editor of the Next at Microsoft blog.

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