Cognitive radio system

• US 20070253394A1
• Filed: 04/27/2007
• Published: 11/01/2007
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Sakata, Ren, Horiguchi, Tomoya, Yoshida, Hiroshi, Tomioka, Tazuko, Nonin, Katsuya
• Granted Patent: US 7,917,110 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 88/14 Backbone network devices

Abstract

A cognitive radio system includes: a state detecting device that scans a frequency band allocated to another radio system than the cognitive radio system to detect a first use-state of the frequency band; a first server including a first gathering unit that receives first information relating to the first use-state and a second gathering unit; a second server that stores a second use-state of the frequency band allocated to the other radio system, the second server configured to provide second information relating to the second use-state to the second gathering unit; and a notifying unit that notifies a terminal device in the cognitive radio system of information of an available channel based on the first information and the second information.

Claims

1. A cognitive radio system comprising:

a state detecting device that scans a frequency band allocated to another radio system than the cognitive radio system to detect a first use-state of the frequency band;

a first server comprising;

a first gathering unit that receives first information relating to the first use-state; and

a second gathering unit;

a second server that stores a second use-state of the frequency band allocated to the other radio system, the second server configured to provide second information relating to the second use-state to the second gathering unit; and

a notifying unit that notifies a terminal device in the cognitive radio system of information of an available channel based on the first information and the second information.

2. The cognitive radio system according to claim 1,

wherein the second use-state stored in the second server is undetectable by the state detecting device.

3. The cognitive radio system according to claim 1,

wherein the first server further comprises a registering unit that organizes and registers in the first server, the first information provided by the first gathering unit and the second information provided by the second gathering unit, and

wherein the notifying unit provides information registered in the first sever to the terminal device.

4. The cognitive radio system according to claim 3,

wherein the state detecting device comprises a position detecting unit that detects a position of the state detecting device and provides position information relating to the detected position to the first server, and

wherein the first server stores the first information provided by the first gathering unit in associated with the position information.

5. The cognitive radio system according to claim 3,

wherein the terminal device comprises a position detecting unit that detects a position of the terminal device, and provides position information relating to the detected position to the first server, and

wherein the first server stores the first information provided by the first gathering unit in associated with the position information.

6. The cognitive radio system according to claim 1,

wherein before the terminal device communicates with another terminal device, the terminal device notifies the first server of information relating to a wireless channel for a communication between the terminal device and the other terminal device.

7. The cognitive radio system according to claim 6,

wherein before the terminal device communicates with the other terminal device, the terminal device further notifies the first server of an estimated communication time of the communication.

8. The cognitive radio system according to claim 7,

wherein the estimated communication time includes a transmission time when the terminal device performs burst communication and a period of the burst communication.

9. The cognitive radio system according to claim 6,

wherein the information relating to a wireless channel for the communication includes a frequency band in which the communication is performed.

10. The cognitive radio system according to claim 1,

wherein the first server calculates a reliability of received information received by the first server.

11. The cognitive radio system according to claim 10,

wherein the first server calculates the reliability so that the reliability is made higher as a distance between a position of the state detecting device and a position of the terminal device is shorter.

12. The cognitive radio system according to claim 10,

wherein the state detecting device notifies the first server of a time when the first use-state is detected, and

wherein the first server calculates the reliability so that the reliability is made higher as a difference between the time when the first use-state is detected and a time when the reliability is calculated is smaller.

13. The cognitive radio system according to claim 10,

wherein the state detecting device notifies the first server of an antenna gain when the state detecting device detects the first use-state, and

wherein the first server calculates the reliability so that the reliability is made higher as the antenna gain is higher.

14. The cognitive radio system according to claim 10,

wherein the state detecting device and the terminal device respectively notify the first server of position information relating to positions of the state detecting device and a position of the terminal device,

wherein the state detecting device notifies the first server of an antenna directivity pattern when the state detecting device detects the first use-state,

wherein the first server calculates an antenna gain based on the antennal directivity pattern and the position information, and

wherein the first server calculates the reliability so that the reliability is made higher as the antenna gain is higher.

15. The cognitive radio system according to claim 10,

wherein the state detecting device comprises a plurality of state detecting devices, and

wherein the first server makes discrimination among the state detecting devices by using a result of accumulation of reliabilities calculated for the state detecting devices.

16. A cognitive radio system comprising:

a wireless access point comprising;

a state detecting unit that scans a frequency band to detect a first use-state of the frequency band; and

a first storage that stores the detected first use-state;

a wireless station that scans the frequency band to detect a second use-state of the frequency band and wirelessly communicates with the wireless access point;

a server that stores a third use-state of another frequency band different from the frequency band allocated to the wireless access point, in a radio system allocated with the other frequency band; and

a wireless device that is coupled to the wireless access point by a wire or wireless and receives a television broadcast,

wherein the wireless access point further comprising;

a gathering unit that respectively gathers information relating to the first to third use-states from the state detecting unit, the wireless station and the server and a fourth use-state of a wireless channel through which the wireless device receives the television broadcast;

a registering unit that registers the information relating to the first to fourth use-states gathered by the gathering unit into the first storage;

a channel selecting unit that selects an available wireless channel from unused wireless channels based on the information relating to the first to fourth use-states registered in the first storage; and

a channel distributing unit that distributes information relating to the available wireless channel selected by the channel selecting unit to the wireless station.

17. The cognitive radio system according to claim 16,

wherein the wireless station and the wireless station are for a local area network.

18. A server in a radio system, the server comprising:

a first gathering unit that receives first information relating to a first use-state of a frequency band allocated to another radio system than the radio system, the first use-state being detected by a state detecting device;

a second gathering unit that receives second information relating to a second use-state of the frequency band allocated to the other radio system; and

a notifying unit that notifies a terminal device in the radio system of an available channel based on the first information and the second information.

19. The server according to claim 18,

wherein the second use-state is undetectable by the state detecting device.