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Global Positioning System (GPS) and Dead-Reckoning are two
major methods often used in modern in-vehicle navigation
system. Using GPS, vehicle position can be located within a
resonable error range. However, in urbanareas, GPS is greatly
affected by the signal visibility problem and is not suitable
to be used as the only positioning source. On the other hand,
Dead-reckoning method uses senseors such as odometers,
compasses, and gyroscopes to measure the vehicle displacement
vectors. These vehicle displacement vectors are then
accumulated successively to obtain the absolute coordinates.
The Dead-reckoning method, being an accumulative process,
suffers from the error accumulation phenomenon. As a result,
integration of GPS with Dead-reckoning system is necessary in
order to obtain a ccurate and reliable vehicle position in
urban enviornments . In this thesis, we concentrate on the
development and testing of a prototype in-vehicle navigation
system. Both the GPS receiver,as well as the Dead-reckoning
sensors including magnetic flux-gate compass, piezoelectric
vibrating gyroscope,and odometer are used as navigation sensors.
Characteristics of these sensors and their special design
considerations will be discussed. Experimential results will
also be presented to demontrate the performance of the GPS/Dead-
reckoning integrated navigation system.
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