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Development of a Low-Cost DGPS/DR System for Vehicle Tracking
1 1 2
Xiufeng He , Thor I. Fossen and Yongqi Chen
Department of Engineering Cybernetics
Norwegian University of Science and Technology, N-7034 Trondheim, Norway
E-mail: xfhe@itk.ntnu.no and tif@itk.ntnu.no
2
Department of Land Surveying and Geo-Informatics
The Hong Kong Polytechnic University, Kowloon, Hong Kong
E-mail: lsypchen@polyu.edu.hk
Key Words: Kalman Filtering, DGPS, Dead-Reckoning, Filtering, Smoothing.
ABSTRACT
This paper presents a low-cost high-
accuracy integrated Differential Global
Positioning System (DGPS) and Dead-
Reckoning (DR) system for navigation. A
low-cost GPS receiver is used as base
station, and it is providing the required
accuracy without the need for a survey
grade receiver. A real-time algorithm for
smoothing of the code pseudorange with
carrier phase measurements is applied. The
smoothing algorithm provides much better
positioning accuracy than DGPS alone.
Since the carrier phase measurements are
sensitive to cycle slips, a method dealing
with cycle slips is proposed. Based on the
smoothing algorithm, a
computational effective 8-state
Kalman filter (KF) is derived for the
integrated DGPS/DR system. For
tracking applications the proposed
KF representation reduces the
computational time with about 50
percent to the standard KF
representation.
1. Introduction
In general, the land vehicle tracking
and navigation systems involve
several techniques like (Driscoll,
1994, and Coltrin et al., 1994):
positioning devices to determine the
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