Communication system using relayed radio channels

• US 6,424,818 B1
• Filed: 02/09/1999
• Issued: 07/23/2002
• Est. Priority Date: 06/24/1997
• Status: Expired due to Term

• Current Assignee: NTT Mobile Communications Network Inc. (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Mobile Communications Network Inc. (Nippon Telegraph and Telephone Corporation)
• Inventors: Hirono, Masahiko
• Primary Examiner(s): MAUNG, NAY AUNG
• Application Number:
  US09/242,217
• Time in Patent Office: 1,260 Days
• Field of Search: 455/557, 455/450, 455/452, 455/466, 455/569, 455/512, 455/514, 455/11.1, 455/15, 370/349, 370/338
• US Class Current: 455/11.1
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

In a communication system, a communication control apparatus is disposed in a mobile object. The communication control apparatus relays information exchanged between a plurality of radio terminals carried into the mobile object and a network side. The communication control apparatus comprises a communication control server which performs establishment of a radio channel between it and a base station at the network side, and establishment of a radio channel between it and a radio terminal according to a communication request from the radio terminal, and a communication unit which performs a radio communication with the radio terminal and a radio communication with the base station, using each radio channel established by the communication control server. The communication control server has an agent function for providing a communication reservation or a packet transmission to a user of a radio terminal in case that it cannot establish a radio channel between it and the base station corresponding to a communication request at a point of time when it has received the communication request from the radio terminal.

Claims

1. A communication system comprising:

a communication network;

one or plural base stations connected with the communication network;

one or plural radio terminals; and

a communication control apparatus disposed between the radio terminal and the base station for relaying information exchanged between the radio terminal and the network by performing a radio communication with the radio terminal and performing a radio communication with the base station;

wherein said communication control apparatus comprises;

a communication control server for performing a channel control between said communication control server and a respective radio terminal, and for performing a channel control between said communication control server and a base station;

a communication unit for performing a radio communication with the radio terminal and the base station using radio channels established by the communication control server; and

wherein said communication unit detects a communication status with the communication network and said communication control server determines whether or not radio communication can be performed with the communication network.

2. A communication system according to claim 1, wherein the communication control apparatus is disposed in a mobile object and performs the relaying operation intended for a radio terminal inside the mobile object.

3. A communication system according to claim 1, wherein the communication control server comprises means for transmitting a rejection of communication request to a radio terminal in response to a communication request received from the same radio terminal, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

4. A communication system according to claim 3, wherein the communication control server comprises means for reserving a communication request received from a radio terminal and for starting communication between the radio terminal and the network side after establishing a radio channel for the communication, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

5. A communication system according to claim 3, wherein the communication control server comprises means for sending a packet transmission request to a radio terminal in response to a communication request received from the same radio terminal, and for storing packets which are received from the radio terminal, and for transmitting the packets thus received to the network after establishing a radio channel for transmitting the packets between the communication control server and a base station, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

6. A communication system according to claim 3, wherein the communication control server comprises means for receiving a plurality of communication requests having different priority from a radio terminal, and performing control of a radio channel between the communication control server and a base station corresponding to a communication request which is one of the communication requests and has a priority lower than a priority of other communication request when the communication control server cannot respond to the communication request having higher priority.

7. A communication system according to claim 3, wherein the communication control server comprises:

(a) means for bringing a real time communication request received from a radio terminal into a reserved state when the communication control server cannot rapidly establish a radio channel between the communication control server and a base station in response to the real time communication request;

(b) means for sending a packet transmission permission notification to the radio terminal when a packet transmission can be accepted during the communication reservation;

(c) means for storing packets which are transmitted from the radio terminal and transmitting the packets to the network side by seizing an opportunity at which the transmission is possible; and

(d) means for making the radio terminal start communication corresponding to the communication request being in a reserved state when the communication control server has established a radio channel for the communication between the communication control server and a base station.

8. A communication system according to claim 3, wherein the communication control server comprises means for converting to each other data sent and received between the communication control server and a radio terminal, and data sent and received between the communication control server and a base station.

9. A communication system according to claim 3, wherein the communication control server comprises a mobile Internet protocol for controlling communication with a LAN.

10. A communication system according to claim 6, wherein the communication control server comprises means for presenting the size of a packet capable of being stored to the radio terminal.

11. A communication system according to claim 3, wherein the communication unit comprises means for detecting radio resources capable of being provided to the radio terminal, and the communication control server performs control for providing a communication service to the radio terminal within the detected radio resources.

12. A communication system according to claim 1, wherein the communication control apparatus comprises detecting means for estimating a time when a communication jamming will happen and, on the basis of the result of estimation, controlling how to handle a communication request from the radio terminal.

13. A communication system according to claim 1, wherein the communication control apparatus comprises judging means for judging a system validity of a radio terminal which has performed a communication request.

14. A communication system according to claim 2, wherein the mobile object is a railway vehicle, an automobile, or a ship.

15. A communication control method for controlling radio communication performed between at least one radio terminal and a communication network comprising the steps of:

providing a communication control apparatus disposed between the radio terminal and a base station of the communication network;

detecting a communication status between the radio terminal and the communication network with the communication control apparatus;

determining whether or not radio communication can be performed with the communication network and the radio terminal with the communication control apparatus; and

establishing radio channels between the radio terminal and the communication network to relay information between the radio terminal and the communication network by performing a radio communication with the radio terminal and performing a radio communication with the base station using the communication control apparatus based on the determination made above.

16. A communication control method according to claim 15, wherein the communication control apparatus transmits a rejection of communication request to a radio terminal in response to a communication request received from the same radio terminal, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

17. A communication control method as defined in claim 15, wherein the communication control apparatus reserves a communication request received from a radio terminal and starts communication between the radio terminal and the network side after establishing a radio channel for the communication, in case that the communication control apparatus cannot establish a radio channel corresponding to the communication request when receiving the communication request.

18. A communication control method as defined in claim 15, wherein the communication control apparatus sends a packet transmission request to a radio terminal in response to a communication request received from the same radio terminal, and stores packets which are received from the radio terminal, and transmits the packets thus received to the network after establishing a radio channel for transmitting the packets between the communication control server and a base station, in case that the communication control apparatus cannot establish a radio channel corresponding to the communication request when receiving the communication request.

19. A communication control method as defined in claim 15, wherein the communication control apparatus sends a packet transmission request to a radio terminal in response to a communication request received from the same radio terminal, and stores packets which are received from the radio terminal, and transmits the packets thus received to the network after establishing a radio channel for transmitting the packets between the communication control server and a base station, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

20. A communication control method as defined in claim 15, wherein the communication control apparatus presents the size of a packet capable of being stored to the radio terminal.

21. A communication control method according to claim 15, wherein the communication control apparatus detects radio resources capable of being provided to the radio terminal and provides a communication service to the radio terminal within the detected radio resources.

22. A communication control method according to claim 15, wherein the communication control apparatus estimates a time when a communication jamming will happen and, on the basis of this result of estimation, controls how to handle a communication request from the radio terminal.

23. A communication control apparatus comprising:

a communication control server for establishing a radio channel between the communication control server and a radio terminal and a radio channel between the communication control server and a base station of a communication network;

a communication unit for performing a radio communication with the radio terminal and a radio communication with the base station, using each radio channel established by the communication control server; and

wherein said communication unit detects a communication status with the communication network and said communication control server judges whether or not the radio communication can be performed with the communication network so that the communication control server can relay communication between the radio terminal and the communication network.

24. A communication control apparatus according to claim 23, wherein the communication control server comprises means for transmitting a rejection of communication request to a radio terminal in response to a communication request received from the same radio terminal, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

25. A communication control apparatus as defined in claim 23, wherein the communication control server comprises means for reserving a communication request received from a radio terminal and for starting communication between the radio terminal and the network side after establishing a radio channel for the communication, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

26. A communication control apparatus according to claim 23, wherein the communication control server comprises means for sending a packet transmission request to a radio terminal in response to a communication request received from the same radio terminal, and for storing packets which are received from the radio terminal, and for transmitting the packets thus received to the network after establishing a radio channel for transmitting the packets between the communication control server and a base station, in case that the communication control server cannot establish a radio channel corresponding to the communication request when receiving the communication request.

27. A communication control apparatus according to claim 23, wherein the communication control server comprises means for receiving a plurality of communication requests having different priority from a radio terminal, and performing control of a radio channel between the communication control server and a base station corresponding to a communication request which is one of the communication requests and has a priority lower than a priority of other communication request when the communication control server cannot respond to the communication request having higher priority.

28. A communication control apparatus according to claim 23, wherein the communication control server comprises:

(a) means for bringing a real time communication request received from a radio terminal into a reserved state when the communication control server cannot rapidly establish a radio channel between the communication control server and a base station in response to the real time communication request;

(b) means for sending a packet transmission permission notification to the radio terminal when a packet transmission can be accepted during the communication reservation;

(c) means for storing packets which are transmitted from the radio terminal and transmitting the packets to the network side by seizing an opportunity at which the transmission is possible; and

(d) means for making the radio terminal start communication corresponding to the communication request being in a reserved state when the communication control server has established a radio channel for the communication between the communication control server and a base station.

29. A communication control apparatus according to claim 23, wherein the communication control server comprises means for converting to each other data sent and received between the communication control server and a radio terminal, and data sent and received between the communication control server and a base station.

30. A communication control apparatus according to claim 23, further comprising a mobile Internet protocol for controlling communication with a LAN.

31. A communication control apparatus according to claim 23, wherein the communication control server comprises means for presenting a size of a packet capable of being stored to the radio terminal.

32. A communication control apparatus according to claim 23, wherein the communication unit comprises means for detecting radio resources capable of being provided to the radio terminal, and the communication control server performs control for providing a communication service to the radio terminal within the detected radio resources.

33. A communication system according to claim 23, further comprising detecting means for detecting a moving state of the communication control apparatus and estimating a time when a communication jamming will happen, wherein the communication system controls how to handle a communication request from the radio terminal on the basis of this result of estimation.

34. A communication control apparatus according to claim 23, further providing judging means for judging a system validity of a radio terminal which has performed a communication request.