A prototype GPS tracking device, designed to be implanted inside a person, has been successfully tested, claims its manufacturer. However, technical experts are questioning whether the system could really work.

The disc-shaped “personal location device” measures 6.35 centimetres in diameter and 1.27 centimetres in depth – roughly the same size as a pace-maker.

Currently it consists of an antenna to receive signals from the satellite constellation that comprises the Global Positioning System and an induction-based power-recharging system. The latter should make it possible to recharge the device’s batteries from outside the user’s body.

Eventually the device will need to connect to a cell phone network if it is to relay the satellite-determined position of its host to another person.
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