BROADCASTING METHOD FOR SENDING SIGNAL CONTAINING PREDETERMINED INFORMATION AND RADIO APPARATUS

• US 20110228866A1
• Filed: 11/27/2009
• Published: 09/22/2011
• Est. Priority Date: 11/28/2008
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Nakaoka, Ken, Nagai, Makoto, Higuchi, Keisuke
• Granted Patent: US 8,861,544 B2
• Time in Patent Office: Days
• US Class Current: 375/259
• CPC Class Codes: G08G 1/093 Data selection, e.g. prioritizing information, managing message queues, selecting the information to be output
• CPC Class Codes: G08G 1/16 Anti-collision systems road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08
• CPC Class Codes: G08G 1/163 involving continuous checking
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 74/0816 with collision avoidance

Abstract

A control information extraction unit receives information on a frame that contains at least a plurality slots from an access control apparatus for controlling communications between radio apparatuses. The control information extraction unit generates a frame that contains at least a plurality of slots in such a manner as to synchronize with the frame corresponding to the received information. An estimation unit (82) estimates empty slots in the plurality of slots generated. A selection unit selects, at random, at least one of the estimated. A modem unit and the like broadcast data using the selected slot.

Claims

1. A radio apparatus, comprising:

a receive unit configured to receive information on a frame that contains at least a plurality slots from an access control apparatus for controlling communications between radio apparatuses;

a generator configured to generate a frame that contains at least a plurality of slots in such a manner as to synchronize with the frame corresponding to the information received by said receive unit;

an estimation unit configured to estimate empty slots in the plurality of slots generated by said generator;

a selection unit configured to select at least one of the empty slots estimated by said estimation unit; and

a broadcasting unit configured to broadcast data using the slot selected by said selection unit.

2. A radio apparatus according to claim 1, wherein said receive unit further receives information on empty slots from the access control apparatus, and

wherein said estimation unit estimates the empty slots, based on the information on empty slots received by said receive unit.

3. A radio apparatus according to claim 2, further comprising an examining unit configured to perform a carrier sense in the respective plurality of slots contained in the frame generated by said generator, and

wherein when said receive unit does not receive the information on empty slots, said estimation unit estimates the empty slots, based on a result of the carrier sense performed by said examining unit.

4. A radio apparatus according to claim 1, further comprising an examining unit configured to perform a carrier sense in the respective plurality of slots contained in the frame generated by said generator, and

wherein said estimation unit estimates the empty slots, based on a result of the carrier sense performed by said examining unit.

5. A radio apparatus according to claim 1, further comprising an examining unit configured to perform a carrier sense in the respective plurality of slots contained in the frame generated by said generator,

wherein said receive unit further receives information on empty slots from the access control apparatus, and

wherein said estimation unit estimates the empty slots, based on the information on empty slots received by said receive unit and a result of the carrier sense performed by said examining unit.

6. A radio apparatus according to claim 5, wherein when the empty slots are not estimated based on the information on empty slots received by said receive unit and the result of the carrier sense performed by said examining unit, said estimation unit estimates the empty slots, based on either one of the information on empty slots received by said receive unit and the result of the carrier sense performed by said examining unit.

7. A radio apparatus according to claim 1, wherein said selection unit selects at least one least one of the empty slots estimated by said estimation unit, at random.

8. A radio apparatus according to claim 7, said selection unit including:

a random number generator for generating a random number;

a divider for dividing the random number generated by the random number generator, by the number of empty slots estimated by said estimation unit; and

an identifying unit for identifying an empty slot whose order counted from a beginning of a frame corresponds to a remainder of the division performed by the divider.

9. A radio apparatus according to any one of claim 1, further comprising a storage configured to store identification numbers used to identify radio apparatuses,

wherein said selection unit selects a slot, based on the identification numbers stored in said storage.

10. A radio apparatus according to claim 1, further comprising a measurement unit configured to measure a distance between the access control apparatus and said radio apparatus,

wherein the respective plurality of slots contained in the frame generated by said generator are associated with the distance, and

wherein said selection unit selects a slot, based on the distance measured by said measurement unit.

11. A broadcasting method, comprising:

receiving information on a frame that contains at least a plurality slots from an access control apparatus for controlling communications between radio apparatuses;

generating a frame that contains at least a plurality of slots in such a manner as to synchronize with the frame corresponding to the received information;

estimating empty slots in the plurality of slots generated by said generating;

selecting at least one of the empty slots estimated by said estimating; and

broadcasting data using the slot selected by said selecting.