Master station, candidate for master station and method for use in a communication system

• US 8,155,082 B2
• Filed: 09/30/2008
• Issued: 04/10/2012
• Est. Priority Date: 08/06/2003
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Yamaguchi, Tsuyoshi, Ohmi, Shinichiro, Yoshizawa, Kensuke
• Primary Examiner(s): Pwu, Jeffrey
• Assistant Examiner(s): Taha, Shaq
• Application Number:
  US12/241,996
• Publication Number:
  US 20090034477A1
• Time in Patent Office: 1,288 Days
• Field of Search: 370/331
• US Class Current: 370/331
• CPC Class Codes: H04W 84/20 Master-slave selection or change arrangements

Abstract

Terminal devices F and G store statistical information related to interference from an external communication system, and notify the stored statistical information to a master station E. The master station E determines the terminal device G as a candidate station for a master station capability handover destination based on collected statistical information. The master station E requests to hand over a master station capability to the terminal device G. If it is determined that the terminal device G accepts handover of the master station capability, the terminal device G starts to act as the master station.

Claims

1. A master station belonging to one of a plurality of communication systems, and having a non-transitory memory having stored therein a program executable by a processor, wherein each of the communication systems includes a master station and at least one slave station, the master station being programmed to operate as:

a request frame transmitting section configured to transmit, to a candidate for a new master station selected from the at least one slave station, a request frame representing a request for the candidate for the new master station to become the new master station;

a response frame receiving section configured to receive, from the candidate for the new master station, a response frame including information indicating whether the request is accepted or not; and

a beacon transmitting section configured to periodically broadcast a beacon frame which includes a value that is decreased by 1 every time the beacon frame is transmitted and that indicates a timing for handover of a master station function when the value becomes 0 until the handover of the master station function is executed and that corresponds to a timing for handover of the master station function between the master station and the candidate for the new master station, the beacon frame also including information indicating that the handover of the master station function is in progress, in order to notify other master stations belonging to other communication systems that the handover of the master station function is in progress, in a case where the response frame includes the information indicating the request is accepted.

2. A candidate for a new master station belonging to one of a plurality of communication systems, and having a non-transitory memory having stored therein a program executable by a processor, wherein each of the communication systems includes a master station and at least one slave station, and a candidate for a new master station is selected from the at least one slave station by the master station, the candidate for the new master station being programmed to operate as:

a request frame receiving section configured to receive, from the master station, a request frame representing a request for the candidate for the new master station to become the new master station, in order to handover a master station function from the master station to the candidate for the new master station;

a response frame transmitting section configured to transmit, to the master station, a response frame including information indicating whether the request is accepted or not;

a beacon receiving section configured to periodically receive, from the master station, a first beacon frame which includes information including a value that is decreased by 1 every time the first beacon frame is transmitted and that indicates a timing for handover of the master station function when the value becomes 0 until the handover of the master station function is executed and that corresponds to a timing for handover of the master station function between the master station and the candidate for the new master station, the first beacon frame also including information indicating that the handover of the master station function is in progress, in order to notify other master stations belonging to other communication systems that the handover of the master station function is in progress, in a case where the response frame includes the information indicating the request is accepted; and

a beacon transmitting section configured to periodically broadcast a second beacon frame which includes information indicating that the handover of the master station function is not in progress, in order to notify the other master stations belonging to the other communication systems that the handover of the master station function is not in progress after the handover of the master station function is executed.

3. A communication method used by a master station belonging to one of a plurality of communication systems, wherein each of the communication systems includes a master station and at least one slave station, the communication method comprising:

transmitting, to a candidate for a new master station selected from the at least one slave station, a request frame for representing a request for the candidate for the new master station to become the new master station, in order to handover a master station function to the candidate for the new master station;

receiving, from the candidate for the new master station, a response frame including information indicating whether the request is accepted or not; and

periodically broadcasting a beacon frame which includes a value that is decreased by 1 every time the beacon frame is transmitted and that indicates a timing for handover of the master station function when the value becomes 0 until the handover of the master station function is executed and that corresponds the timing for handover of the master station function between the master station and the candidate for the new master station, the beacon frame also including information indicating that the handover of the master station function is in progress, in order to notify other master stations belonging to other communication systems that the handover of the master station function is in progress, in a case where the response frame includes the information indicating the request is accepted.

4. A communication method used by a candidate for a new master station belonging to one of a plurality of communication systems, wherein each of the communication systems includes a master station and at least one slave station, and the candidate for the new master station is selected from the at least one slave station by the master station, the communication method comprising:

receiving, from the master station, a request frame representing a request for the candidate for the new master station to become the new master station, in order to handover a master station function from the master station to the candidate for the new master station;

transmitting, to the master station, a response frame including information indicating whether the request is accepted or not;

periodically receiving, from the master station, a first beacon frame which includes information including a value that is decreased by 1 every time the first beacon frame is transmitted and that indicates a timing for handover of the master station function when the value becomes 0 until the handover of the master station function is executed and that corresponds to the timing for handover of the master station function between the master station and the candidate for the new master station, the first beacon frame also including information indicating that the handover of the master station function is in progress, in order to notify other master stations belonging to other communication systems that the handover of the master station function is in progress, in a case where the response frame includes the information indicating the request is accepted; and

periodically broadcasting a second beacon frame which includes information indicating that the handover of the master station function is not in progress, in order to notify the other master stations belonging to the other communication systems that the handover of the master station function is not in progress after the handover of the master station function is executed.