METHOD AND APPARATUS FOR SPECTRUM SHARING BETWEEN AN INCUMBENT COMMUNICATIONS SYSTEM AND A COGNITIVE RADIO SYSTEM

• US 20090034508A1
• Filed: 07/31/2007
• Published: 02/05/2009
• Est. Priority Date: 07/31/2007
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Rao, Yadunandana N., Chaudhri, Apoorv, Gurney, David P., Simms, Matthew E.
• Granted Patent: US 7,881,726 B2
• Time in Patent Office: Days
• US Class Current: 370/351
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition

Abstract

Efficient frequency spectrum sharing between at least one incumbent communication system(s) (102, 152) and at least one cognitive radio (CR) system (105) is provided. The incumbent system'"'"'s system parameters and CR system'"'"'s operational requirements are copied to a mirrored database (106B). The mirrored database (106B) is controlled by a either a central authority (108) or a database manager having delegated authority (508). The mirrored database (106B) is accessed by the CR system (105). The mirrored database (106B) can be modified and updated by the central authority (108) or delegated database manager (508) to correct for interference detected in the incumbent system caused (152) by the cognitive radio system (105). The cognitive radio system (105) utilizes the updated mirrored database (106B) to avoid interfering with the incumbent system (102, 152) to determine CR system operating parameters_thus enhancing the ability to share spectrum.

Claims

1. A means for a plurality of communications systems to share frequency spectrum, comprising:

at least one incumbent communications system;

at least one cognitive radio (CR) communications system operating within CR operating requirements defined by a regulatory body;

a first database having incumbent system parameters, the first database being maintained by a central authority;

a second database having a copy of the CR operating requirements and incumbent system parameters, the second database being maintained by a database manager; and

the second database being updated in response to interference conditions in the incumbent communication system caused by the CR communications system, the updated second database being accessed by the CR communications system to minimize interference with the incumbent communications system.

2. The means for a plurality of communications systems to share frequency spectrum according to claim 1, wherein the first database and second database are stored in a common database.

3. The means for a plurality of communications systems to share frequency spectrum according to claim 1, wherein said CR system periodically accesses the second database for updates.

4. The means for a plurality of communications systems to share frequency spectrum according to claim 1, wherein the incumbent communications system reports interference conditions to the central authority.

5. The means for a plurality of communications systems to share frequency spectrum according to claim 1, wherein the CR communications system utilizes said second database to compute CR system operating parameters.

6. The method of claim 5, wherein said CR system operating parameters comprise at least one of the following:

a transmit power level, an operational frequency, a bandwidth.

7. The method of claim 1, wherein the central authority comprises a regulatory authority.

8. The method of claim 1, wherein the incumbent communications system comprises an existing cognitive radio system.

9. The method of claim 1, wherein the cognitive radio operational requirements are maintained separately for each incumbent system in the second database.

10. A system for enabling a plurality of communication systems to share frequency spectrum, comprising:

at least one incumbent communication system;

at least one cognitive radio (CR) communication system;

a central authority maintaining a database of incumbent system parameters and CR operating requirements;

the central authority providing a mirrored database of the incumbent system parameters and CR operating requirements, the central authority updating the mirrored database in response to interference to the incumbent communication system from the cognitive radio communication system; and

the cognitive radio communication system accessing the updated mirrored database from the central authority to minimize interference and optimize frequency spectrum sharing with the incumbent communication system.

11. The system of claim 10, wherein the incumbent communication system comprises a licensed communication system operating in a licensed band.

12. The system of claim 10, wherein the central authority comprises a regulatory authority.

13. The system of claim 10, wherein the central authority is a licensed spectrum holder.

14. The system of claim 12, wherein the regulatory authority transfers database management to a licensed spectrum holder.

15. The system of claim 14, wherein the licensed spectrum holder enables at least one of:

real time spectrum trading, brokering and bidding in its spectrum holdings.

16. A method for operation amongst a plurality communication systems, comprising:

maintaining a database of incumbent system parameters and CR operational requirements by a central authority;

mirroring the incumbent system parameters and CR operational requirements to a database;

accessing the mirrored incumbent system parameters and CR operational requirements by a cognitive radio system;

determining an operating location of a cognitive radio operating within the cognitive radio system; and

deriving CR system operating parameters for a cognitive radio using the location and mirrored incumbent system parameters and CR operational requirements.

17. The method of claim 16, further comprising the steps of:

detecting interference at the incumbent communication system by the CR system;

reporting the inference to the central authority;

modifying at least one of the mirrored incumbent system parameters and CR operational requirements to alleviate the interference; and

accessing the modified mirrored database by the cognitive unit.

18. The method of claim 16, further comprising:

detecting when the CR radio changes operating location to a new location;

determining the new operation location; and

deriving new CR system operating parameters using the mirrored database parameters and operational requirements.

19. The method of claim 17, further comprising verifying the interference prior to modifying.

20. The method of claim 16, wherein the accessing occurs periodically.

21. A means for sharing frequency spectrum amongst communication systems, comprising:

a primary communication system operating under a licensed transmitter database;

a database manager maintaining a mirrored database of the licensed transmitter database and updating the mirrored transmitter database; and

a secondary communication system accessing information from the updated database to alleviate interference within the frequency spectrum.

22. The means for sharing frequency spectrum amongst communication systems of claim 21, wherein the secondary communication system comprises a public safety communication system.

23. The means for sharing frequency spectrum amongst communication systems of claim 22, wherein the database manager updates the mirrored licensed database to provide priority access to the public safety system during a time of emergency.

24. The means for sharing frequency spectrum amongst communication systems of claim 22, wherein the database manager updates the mirrored licensed database to reserve spectrum for public safety users.

25. The means for sharing frequency spectrum amongst communication systems of claim 22, wherein the mirrored database reserves spectrum for temporary usage by the secondary communication system for public safety emergencies.

26. The means for sharing frequency spectrum amongst communication systems of claim 22, wherein the mirrored database reserves spectrum for temporary usage by predetermined high priority users.

27. The means for sharing frequency spectrum amongst communication systems of claim 22, wherein the database manager is delegated by a central authority.

28. The means for sharing frequency spectrum amongst communication systems of claim 22, wherein the database manager comprises a central authority.

29. A method of sharing spectrum between an incumbent system and a cognitive radio (CR) system operating in the same band, comprising:

mirroring the incumbent system'"'"'s system parameters and CR system'"'"'s operational requirements to a mirrored database;

updating the mirrored database to correct for interference detected in the incumbent system due to the CR system; and

accessing the updated mirrored database by the CR system; and

utilizing the updated mirrored database by the CR system to determine CR system operating parameters.

30. The method of claim 29, further comprising the step of:

maintaining the mirrored database by a central authority.

31. The method of claim 30, wherein the step of maintaining the mirrored database is performed by a database manager delegated by the central authority.

32. The method of claim 30, further comprising the step of trading frequency spectrum via the central database.

33. The method of claim 30, further comprising the step of trading frequency spectrum via the database manager.

34. A spectrum sharing communication network, comprising:

an incumbent communication system;

a cognitive radio (CR) communication system;

a reference database;

a mirrored database having a copy of at least a portion of the reference database; and

a database manager maintaining and updating the mirrored database, the CR communication system utilizing the updated mirrored database to share spectrum with the incumbent communication system.

35. The spectrum sharing communication network of claim 34, wherein the database manager comprises a central authority.

36. The spectrum sharing communication network of claim 34, wherein the database manager comprises a delegated authority.

37. The spectrum sharing communication network of claim 36, wherein the delegated authority is designated by a central authority.

38. The spectrum sharing communication network of claim 34, wherein the reference database comprises incumbent system parameters of the incumbent communication system.

39. The spectrum sharing communication network of claim 34, wherein the reference database comprises incumbent system parameters of the incumbent communication system and CR operating requirements.

40. The spectrum sharing communication network of claim 34, wherein the mirrored database comprises CR operating requirements and incumbent system parameters.