BROADCASTING METHOD, ACCESS CONTROL APPARATUS AND RADIO APPARATUS

• US 20110292918A1
• Filed: 12/24/2009
• Published: 12/01/2011
• Est. Priority Date: 12/25/2008
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Otani, Yoshiyuki, Suzuki, Hanae, Okamura, Yumi
• Granted Patent: US 8,971,297 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04W 74/085 collision avoidance

Abstract

A processing unit generates the timing information on the timing with which each of radio apparatuses is to synchronize in communications between the radio apparatuses when each of radio apparatuses broadcasts a signal. A modem unit, an RF unit and an antenna broadcast the thus generated timing information. The processing unit further generates the cycle information on a broadcast cycle in which each radio apparatus broadcasts the signal in communication between the radio apparatuses. The modem unit, the RF unit and the antenna broadcast the cycle information together with the timing information.

Claims

1. An access control apparatus, comprising:

a generator configured to generate timing information on timing with which each of radio apparatuses is to synchronize in communication between the radio apparatuses when the each of radio apparatuses broadcasts a signal; and

a broadcasting unit configured to broadcast the timing information generated by said generator,

wherein said generator further generates cycle information on a broadcast cycle in which each of the radio apparatuses broadcasts the signal, in communication between the radio apparatuses, and

wherein said broadcasting unit broadcasts the cycle information generated by said generator, together with the timing information.

2. An access control apparatus according to claim 1, further comprising:

an estimation unit configured to estimate a traffic volume in communication between the radio apparatuses; and

a decision unit configured to determine the broadcast cycle according to the traffic volume estimated by said estimation unit.

3. An access control apparatus according to claim 1, wherein said generator generates constraint information on a radio apparatus to be controlled by the cycle information, and

wherein said broadcasting unit broadcasts the constraint information generated by said generator, together with the cycle information.

4. An access control apparatus according to claim 3, wherein said generator generates positional information on a position where the radio apparatus to be controlled is to be located, as the control information.

5. A broadcasting method, comprising:

generating timing information on timing with which each of radio apparatuses is to synchronize in communication between the radio apparatuses when the each of radio apparatuses broadcasts a signal; and

broadcasting the generated timing information,

wherein said generating generates cycle information on a broadcast cycle in which each of the radio apparatuses broadcasts the signal, in communication between the radio apparatuses, and

wherein said broadcasting broadcasts the generated cycle information, together with the timing information.

6. A radio apparatus, comprising:

a receive unit configured to receive, from an access control apparatus for controlling communication between radio apparatuses, timing information on timing with which each of the radio apparatuses is to synchronize when the each of radio apparatuses broadcasts a signal;

a decision unit configured to determine timing synchronized with the timing information received by said receive unit, the timing arriving in a predetermined cycle; and

a broadcasting unit configured to broadcast the signal with the timing determined by said decision unit,

wherein said receive unit further receives, from the access control apparatus, cycle information on a broadcast cycle in which each of the radio apparatuses broadcasts the signal, and

wherein said decision unit adjusts the timing so that the timing arrives with the broadcast cycle according to the cycle information received by said receive unit.

7. A radio apparatus according to claim 6, wherein the access control apparatus determines the cycle information received by said receive unit, according to a traffic volume in communication between the radio apparatuses.

8. A radio apparatus according to claim 6, wherein the cycle information received by said receive unit contains validity information on a period of validity, and

wherein said decision unit adjusts the timing before the period of validity ends so that the signal arrives in the broadcast cycle according to the cycle information received by said receive unit.

9. A radio apparatus according to claim 6, wherein said decision unit adjusts the timing so that the broadcast cycle according to the cycle information takes a minimum cycle.

10. A broadcasting method, comprising:

receiving, from an access control apparatus for controlling communication between radio apparatuses, timing information on timing with which each of the radio apparatuses is to synchronize when the each of radio apparatuses broadcasts a signal;

determining timing synchronized with the received timing information, the timing arriving in a predetermined cycle;

broadcasting the signal with the determined timing;

further receiving, from the access control apparatus, cycle information on a broadcast cycle in which each of the radio apparatuses broadcasts the signal;

adjusting the timing so that the timing arrives with the broadcast cycle according to the received cycle information; and

broadcasting the signal with the adjusted timing.