| 摘要 |
PROBLEM TO BE SOLVED: To efficiently update data which is a retrieval object of a navigation device. SOLUTION: The navigation device 1 receives delivery data 3 from a delivery server 2, but in the delivery data 3, a character string which occurs frequently is substituted with ID. The navigation device 1 has dictionary data 59 associating ID and character strings with each other, and substitutes ID recorded in the delivery data 3, with the corresponding character string in the dictionary data 59 to generate spot information 4 from the delivery data 3. In the delivery data 3, the character string which occurs frequently is the ID smaller in data amount than character data. The data amount transmitted from the delivery server 2 to the navigation device 1 can thereby be reduced. COPYRIGHT: (C)2009,JPO&INPIT |
