Transmission power determination method, communication device and program

1. A method for determining a communication mode information for a second communication service making secondary usage of a spectrum assigned to a first communication service, the method comprising:

determining the communication mode information based on a quality of a first radio signal required in the first communication service, an interference level or a noise level in the first communication service, and a path loss information on a communication path about one or more secondary usage nodes that transmit a second radio signal of the second communication service;

acquiring location data from a database that stores the location data indicating a location of a primary usage node that receives the first radio signal of the first communication service; and

calculating the path loss information on the communication path about the one or more secondary usage nodes based on the location of the primary usage node indicated by the location data and a location of the one or more secondary usage nodes.

2. The method according to claim 1 , wherein

the communication mode information includes at least acceptable transmission power for a second communication service making secondary usage of a spectrum assigned to a first communication service.

3. The method according to claim 1 , wherein

the communication mode information further includes a policy such as a transmission spectrum mask and a modulation method to be complied with by the secondary usage node when making secondary usage of a spectrum.

4. The method according to claim 1 , wherein

the quality of a radio signal required in the first communication service is represented by using a reception level of the first radio signal required in the first communication service and a signal to interference noise ratio.

5. The method according to claim 1 , wherein

the method is executed by the primary usage node that has access to the database, and

the method further comprises notifying the determined a communication mode information from the primary usage node to any node among the one or more secondary usage nodes.

6. The method according to claim 1 , wherein

the method is executed by a node acting as a coordinator of the second communication service among the one or more secondary usage nodes.

7. The method according to claim 1 , wherein

the communication mode information is determined by counting in a margin for reducing a possibility of causing interference on the primary usage node.

8. The method according to claim 7 , wherein

the margin has a value depending on an expected number of the secondary usage nodes.

9. A communication device comprising:

a communication unit to transmit a radio signal of a second communication service making secondary usage of a spectrum assigned to a first communication service; and

a control unit to:

determine a communication mode information for the second communication service, wherein the control unit determines the communication mode information based on a quality of a first radio signal required in the first communication service, an interference level or a noise level in the first communication service, and a path loss on a communication path about one or more secondary usage nodes that transmit a second radio signal of the second communication service;

acquire location data from a database that stores the location data indicating a location of a primary usage node that receives the first radio signal of the first communication service; and

calculate the path loss on the communication path about the one or more secondary usage nodes based on the location of the primary usage node indicated by the location data and a location of the one or more secondary usage nodes.

10. A communication device comprising:

a communication unit to communicate with a secondary usage node that transmits a radio signal of a second communication service making secondary usage of a spectrum assigned to a first communication service; and

a control unit to:

determine a communication mode information for the second communication service, wherein the control unit determines the communication mode information based on a quality of a first radio signal required in the first communication service, an interference level or a noise level in the first communication service, and a path loss information on a communication path about one or more secondary usage nodes, the path loss information is calculated based on the location of the primary usage node indicated by the location data and a location of the one or more secondary usage nodes; and

acquire location data from a database that stores the location data indicating a location of a primary usage node that receives the first radio signal of the first communication service.

11. A secondary usage node comprising:

a communication unit to communicate in a secondary communication service using a spectrum assigned to a first communication service,

wherein a communication mode information for the second communication service is determined based on a quality of a first radio signal required in the first communication service and a path loss information on a communication path about one or more secondary usage nodes including the secondary usage node, and wherein the path loss information is calculated based on a location of a primary usage node indicated by the location data and a location of the one or more secondary usage nodes, the location date being acquired from a database that stores the location date indicating a location of the primary usage node that receives the first radio signal of the first communication service.