Map Matching; High-precision Gyrosensor; GPS signal reception is poor in the following places- Page 371

35

●

If you are using the system for the first time, or if you have not used it for some time, it
takes about 5 minutes (or about 2 minutes in open areas) to calculate your vehicle's
position.

●

The GPS satellites are controlled by the U.S. Defense Department, which may intentionally
lower positioning accuracy. In such cases, there may be vehicle position deviations.

●

There may be vehicle position deviations for some time until GPS signals are received after
turning on the ignition.

■

GPS signal reception is poor in the following places

In tunnels

Among high-rise buildings

Under elevated roads

In wooded areas

GPS

Map Matching

This function compares your vehicle's tracking data with the road data on the map
disc, applies dead reckoning to determine the road you are driving on,
and displays your vehicle on that road on the map.

●

Intelligent map matching addresses the following problems to achieve high accuracy
in vehicle positioning.

Position Correction for Elevated Roads

Position accuracy is improved by detecting if
the vehicle is running on or under an elevated road.

●

Using a spare tire in place of the regular one may cause vehicle position deviations.

●

Any difference between the direction which your vehicle actually travels and that shown
on the map is automatically eliminated by azimuth correction.

GPS is a position detecting system utilizing the signals from
GPS satellites deployed by the U.S. Department of Defense.
The Mobile Navigation System uses input from three or more
satellites and calculates the vehicle position based on the
principle of triangulation.
The positioning accuracy of the system corresponds to the
error display of the GPS which is from about 30 to 200 meters.

Position Correction for Parking Garages

Position accuracy is improved by detecting if the vehicle
is driving in an elevated or underground parking garage.

High-precision Gyrosensor

A gyro detects turns with an accuracy of 0.05˚ per second.
Combined with a speed sensor, it enables the system to display
the current vehicle position even where GPS signals may be 
blocked.

As necessary

ance

bout.

second

ogether,

may be late.

 direction.

nd it cannot

uld always

able at

sc. You
hospital or

e closed

e the time

riving.

e and may

rking brake

e 32.

the map by

tire

ehicle.

tions.