Patent ID: 7139663
Filing Date: 2006-11-21
Classification: G01C

Abstract:
1. A navigation apparatus comprising: an input device for inputting a destination or a place on route as a retrieve condition; a transmitting and receiving device for transmitting the input retrieve condition to an external center and for receiving from the external center road data which corresponds to the retrieve condition, said road data including groups of data each group having road data of the same type of roads and said type of roads for each group being different from the other types of roads of the other groups, said groups being separated by delimiters and being seguentially transmitted in accordance with a transmitting priority order of road data, which is given beforehand, indicating priority of display of the different types of roads; and a display controller for displaying a map up to road data of the type of roads of a group of which reception has been completed when road data reception is interrupted by radio disturbance.