It is the GPS receiver which does determination calculation making use of the GPS receiver null Kalman filter which outputs

摘要

PROBLEM TO BE SOLVED: To provide a GPS receiver outputting 2DRMS which properly reflects actual positioning error included in a GPS positioning solution, and to provide a car navigation device using the GPS receiver.;SOLUTION: In the GPS receiver, using a Kalman filter for computing a positioning solution, using a horizontal (latitude, longitude) directional estimation error (σ H-Kalman), which is computed form a diagonal element of an error covariance matrix computed in a computing process of a Kalman filter estimation value, 2DRMS is computed according to a definition represented by 2DRMS=2.{(σ H-Kalman)2+(HDOP.σUERE)2}1/2 which is outputted with the GPS positioning solution. An application program for performing car navigation determines the accuracy of the GPS positioning solution by using this 2DRMS.;COPYRIGHT: (C)2001,JPO