Mobile terminal and a server for navigation system

• US 20010005809A1
• Filed: 01/25/2001
• Published: 06/28/2001
• Est. Priority Date: 06/22/1999
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Ito, Takashi
• Granted Patent: US 6,347,278 B2
• Time in Patent Office: Days
• US Class Current: 701/210
• CPC Class Codes: G01C 21/3415 Dynamic re-routing, e.g. recalculating the route when the user deviates from calculated route or after detecting real-time traffic data or accidents
• CPC Class Codes: G01C 21/3611 using character input or menus, e.g. menus of POIs character input methods in general G06F3/0233
• CPC Class Codes: G08G 1/096811 where the route is computed offboard
• CPC Class Codes: G08G 1/096861 where the immediate route instructions are output to the driver, e.g. arrow signs for next turn
• CPC Class Codes: G08G 1/096872 where instructions are given per voice
• CPC Class Codes: G08G 1/096883 where input information is obtained using a mobile device, e.g. a mobile phone, a PDA
• CPC Class Codes: G08G 1/096894 where input is assisted by the navigation device, i.e. the user does not type the complete name of the destination, e.g. using zip codes, telephone numbers, progressively selecting from initial letters

Abstract

A navigation system in which a mobile terminal side 101 is not equipped with a CD-ROM for storing map database 105, but implements an on-demand navigation function by sharing the one provided within a server 102. By limiting the communications between the mobile terminal 101 and the server 102 only to the beginning of the route guidance and the moment at which the mobile terminal has deviated from the route, the communication traffic can be reduced, minimizing thereby the communication cost and the total power consumption as a whole, and further even when the mobile terminal 101 has deviated from the guide route, the system can readily provide the user with information by which he can reach his destination through communications with the server, and enabling also an indication of the name of the road to be taken at every crossings.

Claims

1. A mobile terminal in a navigation system, which carries out communications by way of a communication line including a wireless telephone line and provides a route guidance for users on the basis of the data obtained by the communications, said mobile terminal comprising:

a location detection means for detecting the location of the mobile terminal itself,

a receiving means for receiving a first recommendable travelling route data transmitted by way of said communication line as a first information, said route data covering a first condition based on the starting point data and the destination data of itself,

a comparing means for comparing said first recommendable travelling route data with a location detected by said location detection means,

an indication means for indicating a direction to which the user should move on the basis of the result of the comparison made by said comparing means, and

a new route requesting means for transmitting a request for a new second recommendable travelling route data to said communication line on the basis of the result of the comparison, said second recommendable travelling route data covering a second condition based on the location of the mobile terminal itself detected by said location detection means and said destination data,

wherein said receiving means receives said new second recommendable travelling route data transmitted by way of said communication line as a second information, and said comparing means also compares said second recommendable travelling route data with a location detected by said location detection means.

2. The mobile terminal in a navigation system according to

claim 1

further comprising a transmission means for transmitting the location information and the destination information of itself to the communication line as a first condition.

3. The mobile terminal in a navigation system according to

claim 1

further comprising a return indication means, which, in the case where a deviation of its location from the recommendable travelling route is detected on the basis of the result of the comparison conducted in said comparing means, indicates the direction in which the nearest recommendable travelling route resides to the user.

4. The mobile terminal in a navigation system according to

claim 1

further comprising a return indication means, which, in the case where a deviation of its location from the recommendable travelling route is detected on the basis of the result of the comparison conducted in said comparing means, indicates the direction reverse to the recommendable travelling route after the deviation to the user.

5. The mobile terminal in a navigation system according to

claim 1

further comprising;

a storage means for storing the data received through the communication line into a memory,

a processing means for sequentially processing the data received through said communication line,

a memory monitoring means for monitoring as to whether or not the summed amount of the memory area which has been made available after the completion of processing conducted by said processing means and unused memory area is substantially great, and

a continued data requesting means, which, in the case where the result of the monitoring is substantially great and it is indicated that the received data contains a continued data, transmits a request for transmission of said continued data to said communication line.

6. The mobile terminal in a navigation system according to

claim 5

further comprising a data amount informing means for transmitting a notification of the amount of data storable in the memory to the communication line, in advance of receiving data by way of the communication line.

7. The mobile terminal in a navigation system according to

claim 5

further comprising an interruption requesting means, which, in the case where the result of the monitoring conducted by said memory monitoring means has become small during the data reception by way of the communication line, transmits a request for interruption of the data transmission to the communication line.

8. A server in a navigation system, which comprises a map database, and transmits data for providing a route guidance for users on the basis of said map database by the communications conducted by way of a communication line including a wireless telephone line, said sever comprising:

a request receiving means for receiving the starting point information and the destination information of itself transmitted by way of said communication line as a condition,

a route extracting means for extracting a recommendable travelling route by referring to said map database in accordance with the condition received by said request receiving means,

a transmission means for transmitting the recommendable travelling route extracted by said route extracting means by way of said communication line, and

a destination setting information transmission means for transmitting destination setting information to said communication line in the order of upper to lower layers, in response to the request received by way of said communication line.

9. The server in a navigation system according to

claim 8

, further comprising:

a condition receiving means for receiving the condition for data transmission and a data-storage use memory amount data, both transmitted through the communication line,

a processing means for carrying out processing on the basis of the condition for data transmission,

a transmission means for transmitting the result of the processing conducted by said processing means,

a data amount limiting means for limiting the amount of data transmitted from said transmission means to the level below said data storage-use memory amount data, and

a continued information adding means for adding the information indicating that there exists continued data to the data transmitted to said communication line.