Broadcasting method for sending signal containing predetermined information and radio apparatus

• US 9,210,724 B2
• Filed: 09/11/2014
• Issued: 12/08/2015
• Est. Priority Date: 11/28/2008
• 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: Nagai, Makoto, Nakaoka, Ken, Higuchi, Keisuke
• Primary Examiner(s): CHAN, SAI MING
• Application Number:
  US14/484,086
• Publication Number:
  US 20150030009A1
• Time in Patent Office: 453 Days
• Field of Search: 370/336
• US Class Current: 1/1
• 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 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 terminal apparatus comprising:

a receiving unit adapted to a system where a period in which an access control apparatus is configured for broadcasting an orthogonal frequency division multiplexing (OFDM) packet signal is defined as a first period and a period available for carrier sense multiple access with collision avoidance (CSMA/CA) communication between terminal apparatuses is defined as a second period, where a 100 msec frame is formed by time division multiplexing a plurality of first periods and a second period, and where a plurality of access control apparatuses use mutually different first periods, the receiving unit being further adapted to receive, in the first period used by one of the access control apparatuses, an OFDM packet signal from the one of the access control apparatuses; and

a transmitting unit that broadcasts, given a 100 msec frame in which a plurality of first periods and the second period are time division multiplexed, an OFDM packet signal in the second period,

wherein the OFDM packet signal received by the receiving unit includes information on timing of the first periods in which the one of the access control apparatuses broadcasts an OFDM packet signal, and

the transmitting unit performs carrier sensing and determines random timing of transmission.

2. The terminal apparatus according to claim 1, wherein the transmitting unit generates a random number to determine random timing of transmission.

3. The terminal apparatus according to claim 1, wherein the receiving unit establishes synchronization based on the received OFDM packet signal.

4. A communication method adapted to a system where a period in which an access control apparatus is configured for broadcasting an orthogonal frequency division multiplexing (OFDM) packet signal is defined as a first period and a period available for carrier sense multiple access with collision avoidance (CSMA/CA) communication between terminal apparatuses is defined as a second period, where a 100 msec frame is formed by time division multiplexing a plurality of first periods and a second period, and where a plurality of access control apparatuses use mutually different first periods, the receiving unit being further adapted to receive, in the first period used by one of the access control apparatuses, an OFDM packet signal from the one of the access control apparatuses, the method comprising:

receiving, in the first period used by one of the access control apparatuses, an OFDM packet signal from the one of the access control apparatuses; and

broadcasting, given a 100 msec frame in which a plurality of first periods and the second period are time division multiplexed, an OFDM packet signal in the second period,

wherein the OFDM packet signal received in the receiving includes information on timing of the first periods in which the one of the access control apparatuses broadcasts an OFDM packet signal, and

the transmitting performs carrier sensing and determines random timing of transmission.