IPS -- Indoor Positioning Systems

clipped from www.sciam.com

A Positioning System That Goes Where GPS Can't

Indoor positioning system technology uses radio, ultrasound or infrared signals to more precisely track locations where GPS signals are blocked

Global positioning system (GPS) technology—now found in everything from cars to wristwatches—has become increasingly popular over the past few years for tracking location. But it has its limits—most notably, roofs, walls and floors that shield satellite signals and keep them from locating GPS receivers indoors.

clipped from www.sonitor.com
The Sonitor ultrasound indoor positioning system (IPS) automatically tracks precisely by room the real-time location of moveable equipment and people in complex indoor environments.
The Sonitor IPS represents a robust, virtually fail-safe, yet simple tracking solution to your complex challenge.
clipped from www.sonitor.com
The Ultrasound Advantage

The Sonitor system uses ultrasound as its means of communications. Ultrasound has several desirable properties that make it ideal for this application.

clipped from www.sonitor.com

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A Positioning System That Goes Where GPS Can't: Scientific American
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