Communication navigation system, communication navigation method, route guidance information transmitting device, and terminal unit

A communication navigation method for performing navigation, using map data stored in a server and current position data about a navigation terminal, by transmitting the map data to the navigation terminal via a communication network, the communication navigation method comprising:

• a first procedure in which the navigation terminal requests the server to transmit an information segment necessary for a first current part of guidance via the communication network;
• a second procedure in which the server transmits to the navigation terminal the information segment requested by the first procedure, via the communication network;
• a third procedure in which after the second procedure, the navigation terminal requests the server to transmit an information segment necessary for a second current part of the guidance via the communication network;
• and
• a fourth procedure in which the server transmits to the navigation terminal the information segment requested by the third procedure, via the communication, network,
• wherein the information segment transmitted by the fourth procedure is an update of the information segment transmitted by the second procedure.

A communication navigation system for performing navigation, using map data stored in a server and current position data about a navigation terminal, by transmitting the map data to the navigation terminal via a communication network, the communication navigation system comprising:

• a navigation terminal which requests a server to transmit an information necessary for an immediate part of guidance via the communication network;
• and
• a server which transmits the requested information to the navigation terminal via the communication network,
• wherein the server transmits updated information to the navigation terminal when the server receives the request from the navigation terminal.

A communication navigation system for implementing a communication navigation method for performing navigation, using map data stored in a server and current position data about a navigation terminal, by transmitting the map data to the navigation terminal via a communication network, the communication navigation method comprising:

• a first procedure in which the navigation terminal requests the server to transmit an information segment necessary for a first current part of guidance via the communication network;
• a second procedure in which the server transmits to the navigation terminal the information segment requested by the first procedure, via the communication network;
• a third procedure in which after the second procedure, the navigation terminal requests the server to transmit an information segment necessary for a second current part of the guidance via the communication network;
• and
• a fourth procedure in which the server transmits to the navigation terminal the information segment requested by the third procedure, via the communication network,
• wherein the information segment transmitted by the fourth procedure is an update of the information segment transmitted by the second procedure.

A terminal unit that implements a communication navigation method for performing navigation, using map data stored in a server and current position data about a navigation terminal, by transmitting the map data to the navigation terminal via a communication network, as the navigation terminal, the communication navigation method comprising:

• a requesting process in which the navigation terminal requests the server to transmit an information necessary for an immediate part of guidance via the communication network;
• and
• a transmitting process in which the server transmits the requested information to the navigation terminal via the communication network,
• wherein the server transmits updated information to the navigation terminal when the server receives the request from the navigation terminal.

A terminal unit that implements a communication navigation method for performing navigation, using map data stored in a server and current position data about a navigation terminal, by transmitting the map data to the navigation terminal via a communication network, as the navigation terminal, the communication navigation method comprising:

• a first procedure in which the navigation terminal requests the server to transmit an information segment necessary for a first current part of guidance via the communication network;
• a second procedure in which the server transmits to the navigation terminal the information segment requested by the first procedure, via the communication network;
• a third procedure in which after the second procedure, the navigation terminal requests the server to transmit an information segment necessary for a second current part of the guidance via the communication network;
• and
• a fourth procedure in which the server transmits to the navigation terminal the information segment requested by the third procedure, via the communication network,
• wherein the information segment transmitted by the fourth procedure is an update of the information segment transmitted by the second procedure.