Automotive Dead Reckoning (ADR) is a navigation aid that greatly improves the positioning ofGlobal Navigation Systems (GNSS). Another one is Untethered Dead Reckoning
(UDR). One of the problems encounter
ed innavigation and position accuracy
arises in urban areas when the motor vehicle performs location determination in urban canyons, in the shadow of skyscrapers, or in tunnels. The automotive dead reckoning techniquecan
compensate for inaccuracies by comparing
the current position with the last GNSS position and calculating a correction.