Acura 3.5 RL Manual page 1293

Description
Navigation Function (cont'd)
Navigation Unit
The navigation unit calculates the vehicle position and guides you to the destination. The unit performs map matching
correction, GPS correction, and distance tuning. It also controls the menu functions and the DVD-ROM drive (hard disk
drive '96 - 99 models). With control of all these items, the navigation unit makes the navigation picture signal, then it
transmits the signal to the display unit and audio driving instructions to the audio unit.
Calculation of Vehicle Position
The navigation unit calculates the vehicle position (the driving direction and the current position) by receiving the direc-
tional change signals from the yaw rate sensor and the travel distance signals from the vehicle speed sensor (VSS).
Map Matching Tuning
The map matching tuning is accomplished by indicating the vehicle position on the roads on the map. The map data
transmitted from the DVD-ROM (hard disk '96 - 99 models) is checked against the vehicle position data, and the vehicle
position is indicated on the nearest road. Map matching tuning does not occur when the vehicle travels on a road not
shown on the map or when the vehicle position is far away from a road on the map.
GPS Tuning
The GPS tuning is accomplished by indicating the vehicle position as the GPS's vehicle position. The navigation unit com-
pares its calculated vehicle position data with the GPS vehicle position data. If there is large difference between the two,
the indicated vehicle position is adjusted to the GPS vehicle position.
Distance Tuning
The distance tuning reduces the difference between the travel distance signal from the VSS and the distance data on the
map. The navigation unit compares its calculated vehicle position data with the GPS vehicle position data. The navigation
unit then decreases the tuning value when the vehicle position is ahead of the GPS vehicle position, and it increases the
tuning value when the vehicle position is behind the GPS vehicle position.
Route Guidance
The navigation unit can calculate different routes to a selected destination. You have four options:
• Direct Route — Calculate a route that is the most direct and will take the least time.
• Easy Route — Calculate a route that minimizes the number of turns needed.
• Minimize Freeways — Calculate a route that avoids freeway travel. If that is not possible, keep the amount of freeway
travel to a minimum.
• Minimize Toll Roads — Calculate a route that avoids or minimizes travel on toll roads
Audio Guidance
The navigation unit transmits audio driving instructions before entering an intersection or passing a junction.
The audio instructions come through audio unit and the front speakers.
DVD-ROM ('00 - 01 models). Hard Disk ('96 - 99 models)
The map data (including all scale rates) is stored in the DVD-ROM/Hard Disk. The map data includes:
• Road distances, road widths, speed limits, traffic regulations, passing time at junction, distances to junctions, and the
driving instructions for audio guidance.
• Latitude and longitude for GPS.