SYSTEM AND METHOD FOR MAINTAINING A BACKUP RADIO OPERATING PARAMETER LIST IN A SECONDARY USE COMMUNICATION SYSTEM

• US 20100238798A1
• Filed: 03/23/2009
• Published: 09/23/2010
• Est. Priority Date: 03/23/2009
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Gurney, David P., Ahuja, Ramandeep
• Granted Patent: US 8,305,917 B2
• Time in Patent Office: Days
• US Class Current: 370/225
• CPC Class Codes: H04L 41/0681 Configuration of triggering conditions
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04W 12/084 using delegated authorisation, e.g. open authorisation [OAuth] protocol
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 48/00 Access restriction access security to prevent unauthorised access H04W12/08; Network selection; Access point selection

Abstract

A radio communication system (100) provides a radio air interface at a master node (102) for subscriber units associated with the master node. Among the subscriber units are several slave nodes (104, 106). The communication system has the ability to operate as a secondary user in unused spectrum portions of a frequency band otherwise reserved for primary operators, such as licensed broadcasters. The master node accesses an authorization server (108) to obtain a list of unused channels in the region of the master node. Each slave node also contacts the authorization server to obtain a list of unused channels in the region where each respective slave node is located, via another network (118, 121). The unused channels common to the slave nodes and the master node are used to create a backup radio operating parameter list which is used by the master node if a fault occurs between the master node the authorization server.

Claims

1. A method for acquiring radio operating parameters in a radio communications network, comprising:

obtaining, at a first radio node in the radio communications network, first radio operating parameters from at least one authorization server, the first radio operating parameters based on a location of at least one node in the radio communications network;

obtaining, at a second radio node in the radio communications network which is in radio communication with the first radio node, second radio operating parameters from an authorization server, the second radio operating parameters based on a location of the at least one radio node;

exchanging the first and second radio operating parameters amongst the first and second radio nodes;

determining common radio operating parameters from the first and second radio operating parameters; and

distributing the common radio operating parameters to the first and second radio nodes.

2. The method of claim 1, wherein the step of determining radio operating parameters comprises selecting common radio operating parameters from the first and second radio operating parameters.

3. The method of claim 1, wherein the first and second radio operating parameters comprise at least one of the following:

a channel availability list, a maximum allowed transmit power level, an operating frequency, an operational bandwidth, or an interference level.

4. The method of claim 1, wherein the first node is a master node, the method further comprises, upon detection of a fault at the master node preventing further obtaining of radio parameters from the authorization server, at least the second radio node commences operating in accordance with common radio operating parameters.

5. The method of claim 1, wherein the at least one radio node obtains the radio operating parameters over a secondary communication system.

6. A method for maintaining a backup radio operating parameter list in a secondary use communication system, comprising:

obtaining, at a master node, a master radio operating parameter list from an authorization server, wherein the master radio operating parameter list is based on a location of the master node;

assigning a plurality of slave nodes that are in radio association with the master node to each acquire a slave radio operating parameter list from the authorization server based on the locations of each of the slave nodes and using a different network than used by the master node to obtain the master radio operating parameter list;

deriving the backup radio operating parameter list from the master and slave radio operating parameter lists; and

distributing the backup radio operating parameter list to at least one slave node.

7. The method of claim 6, wherein the radio operating parameter lists indicate available television broadcast channels in the vicinity of the master and slave nodes.

8. The method of claim 6, wherein each of the slave nodes obtain the slave radio operating parameter lists by using one of a wireless local area network, a public safety radio network, or a cellular telephony network.

9. The method of claim 6, wherein the backup radio operating parameter list is substantially the intersection of available channels in the master and slave radio operating parameter lists.

10. The method of claim 9, wherein, when upon first determining the intersection the number of available channels is less than a preselected number of channels, at least one slave radio operating parameter list is dropped from consideration, the intersection is then found with the remaining slave radio operating parameter lists, and the slave node corresponding to the dropped slave radio operating parameter list is removed from association with the master node.

11. The method of claim 10, wherein the dropped slave node is selected by determining the slave radio operating parameter list having a fewest number of common channels with the master and other slave radio operating parameter lists.

12. The method of claim 10, wherein the dropped slave node is selected by determining a slave node having a lowest communication activity level among the slave nodes.

13. The method of claim 6, wherein the method is repeated periodically and upon the occurrence of an error preventing the master node from obtaining a present master radio operating parameter list, selecting channels from the backup radio operating parameter list.

14. The method of claim 6, wherein assigning the plurality of slave nodes comprises selecting slave nodes that are geographically dispersed in a serving region of the master node.

15. A communication system providing fault tolerance when operating in secondary-use mode, comprising:

a master node configured to provide a radio communication air interface in the vicinity of the master node, wherein the master node is further configured to obtain a master radio operating parameter list for secondary-use operation from an authorization server, the master radio operating parameter list indicating available channels for secondary-use at a location of the master node;

a plurality of slave nodes associated with the master node via the radio communication air interface, wherein each slave node obtains, from the authorization server via an alternative network access point, a slave radio operating parameter list, each slave radio operating parameter list indicating available channels for secondary-use at a location of the requesting slave node;

wherein the communication system creates a backup radio operating parameter list of channels common to the master and slave radio operating parameter lists, and wherein upon the occurrence of a fault between the master node and the authorization server the backup radio operating parameter list is used to select channels for secondary use.

16. The communication system of claim 15, wherein the master node creates the backup radio operating parameter list.

17. The communication system of claim 16, wherein the master node distributes the backup radio operating parameter list to the slave nodes.

18. The communication system of claim 16, wherein the radio operating parameter lists indicate unused television broadcast channels in the vicinity of the master and slave nodes.

19. The communication system of claim 16, wherein each of the slave nodes obtain the slave radio operating parameter lists by using one of a wireless local area network, a public safety radio network, or a cellular telephony network.

20. The communication system of claim 16, wherein the backup radio operating parameter list is created by selectively excluding slave radio operating parameter lists until at least a preselected number of common channels are found, and wherein the master node de-associates from slave nodes whose slave radio operating parameter lists have been excluded.

21. The communication system of claim 20, wherein the excluded slave radio operating parameter list is selected by determining the slave radio operating parameter list having a fewest number of common channels with the master and other slave radio operating parameter lists.

22. The communication system of claim 19, wherein the excluded slave radio operating parameter list is from a slave node having a lowest communication activity level.