The Radio Interferometric Positioning System (RIPS) utilizes standard MICA2 motes for self localization.
relies on a pair of nodes emitting radio waves simultaneously
at slightly different frequencies. The carrier frequency of the
composite signal is between the two frequencies, but has a
very low frequency envelope. Neighboring nodes can measure
the energy of the envelope signal as the signal strength.
The relative phase offset of this signal measured at two receivers
is a function of the distances between the four nodes
involved and the carrier frequency. By making multiple measurements
in an at least 8-node network, it is possible to
reconstruct the relative location of the nodes in 3D. Our
prototype implementation on the MICA2 platform yields
an average localization error as small as a few centimeters at a range of
up to 170 meters. In addition to this high precision and long
range, the other main advantage of the Radio Interferometric
Positioning System (RIPS) is the fact that it does not
require any sensors other than the radio used for wireless
RIPS was presented at SenSys 2005 in San Diego in November. Check out the paper or the presentation.
Node Density Independent Localization paper was presented at IPSN 2006 conference. Check out the paper or the presentation
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