COMMUNICATION METHOD, COMMUNICATION DEVICE, AND COMPUTER PROGRAM

• US 20070184780A1
• Filed: 04/10/2007
• Published: 08/09/2007
• Est. Priority Date: 02/03/2003
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: SAKODA, Kazuyuki
• Granted Patent: US 7,844,223 B2
• Time in Patent Office: Days
• US Class Current: 455/41.200
• CPC Class Codes: H04W 40/244 using a network of reference devices, e.g. beaconing
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 72/53 based on regulatory allocation policies
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 84/20 Master-slave selection or change arrangements

Abstract

In order to solve a problem of an accumulation on the transmission side, a delay on the reception side, and the like at the time of transmission in a communication system such as a wireless LAN system, each communication station in a network transmits a beacon in which information with respect to the network is written and sets a state in which a reception operation is performed during periods of time before and after the transmission of the beacon signal when performing access control not to make communication timing of a packet collide with that of another station by detecting a signal transmitted from another station. With performing such processing, a system can be formed based on minimum level of transmission and reception operation when transmission and reception data does not exist in each communication station in the network, and also a data transfer can be performed with latency as small as possible in a minimum necessary level of transmission and reception operation by making a transition of a transmission and reception state in accordance with a fluctuating volume of transmission and reception data.

Claims

1. :

A communication method of performing wireless communication in a self-organized network, each station having a plurality of active levels for power management, comprising;

transmitting from a communication station a beacon signal in which information with respect to the network is written; and

setting by the communication station a state in which a reception operation is performed during a period of time before and after the transmitting of said beacon signal.

2. :

A communication method according to claim 1, further comprising;

periodically transmitting said beacon signal from a communication station in an active state in the network.

3. :

A communication method according to claim 2, further comprising;

changing over a plurality of transmission active levels or a plurality of reception active levels in each communication station in accordance with a presence or absence of transmission data or a request for active level change from a communication partner.

4. :

A communication method according to claim 2, further comprising;

setting a state in which a reception operation is performed over a beacon signal transmission interval in predetermined cycles.

5. :

A communication method according to claim 1, further comprising;

setting by said communication station a state in which a reception operation is performed during a period of time in which the beacon signal is transmitted by a partner station having a possibility of generating data to be transmitted and during a neighboring period of time thereof.

6. :

A communication method according to claim 1, further comprising;

exchanging by said communication station messages in order to transmit data with a communication station to which data should be transmitted when the data to be transmitted is generated; and

setting by said communication station a state in which a reception operation is performed during a period of time in which said communication partner station transmits a beacon signal and during a neighboring period of time thereof.

7. :

A communication method according to claim 2, further comprising;

generating at least one transmission trigger time between beacon signal transmission intervals, and

starting a procedure of transmission or reception based on said transmission trigger time.

8. :

A communication method according to claim 1, further comprising;

writing communication state information of a communication station capable of performing communication within said network as said information with respect to the network written in the beacon signal, and retaining in the communication system said communication state information.

9. :

A communication method according to claim 8, further comprising;

changing said retained communication state information in accordance with presence or absence of transmission data or received communication state change request information.

10. :

A communication method according to claim 1, further comprising;

informing from a communication station transmitting broadcast information to each communication station recognized that transmission and reception is directly performed therefrom, that the communication station is in a state in which a reception operation is performed during a period of time in which a communication partner station transmits a beacon signal and also during a neighboring period of time thereof; and

transmitting said broadcast information.

11. :

A communication method according to claim 10, further comprising;

transmitting said broadcast information by a beacon signal or a packet which follows the beacon signal.

12. :

A communication method according to claim 10, further comprising;

retaining communication state information on a communication station capable of performing communication in said network as a list and changing a retained status based on a transmitted change notice.

13. :

A communication method according to claim 10, further comprising;

informing by a beacon signal a reception state thereof or a status with respect to a reception state.

14. :

A communication apparatus which operates in a network built under a wireless communication environment of an autonomous distributed type, comprising;

a communication unit configured to transmit and receive wireless data;

a beacon generation unit configured to generate a beacon signal in which information with respect to the network is written to be transmitted by said communication unit; and

a control unit configured to set a state in which a reception operation is performed during periods of time before and after transmission of the beacon signal generated by said beacon generation unit.

15. :

A communication apparatus according to claim 14, wherein

the beacon generation unit is configured to generate a signal and configured to periodically transmit the signal when the communication apparatus is in an active state.

16. :

A communication apparatus according to claim 15, wherein

said control unit is configured to change over a plurality of transmission active levels or a plurality of reception active levels in accordance with presence or absence of transmission data or a request for active level change from a communication partner.

17. :

A communication apparatus according to claim 15, wherein

said control unit is configured to set a state in which a reception operation is performed by said communication unit over a beacon signal transmission interval in predetermined cycles.

18. :

A communication apparatus according to claim 14, wherein

said control unit is configured to set a state in which a reception operation is performed by said communication unit during a period of time in which a communication partner having a possibility of generating data to be transmitted transmits a beacon signal and during a neighboring period of time thereof.

19. :

A communication apparatus according to claim 14, wherein

said control unit is configured to control an exchange of messages in order to transmit data with a communication partner to whom data should be transmitted when the data to be transmitted is generated, and to set a state in which a reception operation is performed by said communication unit during a period of time in which said communication partner transmits a beacon signal and during a neighboring period of time thereof.

20. :

A communication apparatus according to claim 15, wherein

said control unit is configured to generate at least one transmission trigger time between beacon signal transmission intervals, and to start a procedure of transmission or reception in said communication unit based on said transmission trigger time.

21. :

A communication apparatus according to claim 14, wherein

said beacon generation unit is configured to generate the beacon including information with respect to the network written being communication state information on a communication apparatus capable of performing communication in said network, and

said control unit is configured to retain said communication state information written in said beacon signal received by said communication unit.

22. :

A communication apparatus according to claim 14, wherein

said control unit is configured to change said retained communication state information in accordance with presence or absence of transmission data or received communication state change information.

23. :

A communication apparatus according to claim 14, wherein

the control unit is configured to inform each communication apparatus recognized to perform transmission and reception directly with the relevant communication apparatus, that the communication apparatus is in a state in which a reception operation is performed during a period of time in which a communication partner transmits a beacon signal and during a neighboring period of time thereof when broadcast information is transmitted from said communication unit.

24. :

A communication apparatus according to claim 23, wherein

said transmitter is configured to transmit said broadcast information in a beacon signal or a packet that follows the beacon signal.

25. :

A communication apparatus according to claim 23, wherein

said control means is configured to retain, as a list, communication state information on a communication apparatus capable of performing communication in the network, and to change the retained status based on a change notice received by said communication unit.

26. :

A communication apparatus according to claim 23, wherein

said control unit is configured to add a reception state thereof or a status with respect to the reception state to the beacon signal generated by said beacon generation unit to be transmitted from said communication unit.

27. :

A computer readable recording medium that records a program for performing access control not to make communication timing of a packet collide with that of another station by detecting a signal transmitted from another station in a network including a plurality of communication stations and causes a computer to execute;

transmitting a beacon in which information with respect to the network is written; and

setting a state in which a reception operation is performed during periods of time before and after the transmission of said beacon signal.