COMMUNICATION SYSTEM, DEPENDENT STATION THEREOF AND DEPENDENT-STATION RELAY TRANSMISSION METHOD

• US 20110096716A1
• Filed: 07/17/2009
• Published: 04/28/2011
• Est. Priority Date: 08/28/2008
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kanda, Tetsuo
• Granted Patent: US 8,848,595 B2
• Time in Patent Office: Days
• US Class Current: 370/315
• CPC Class Codes: H04H 20/08 among terminal devices
• CPC Class Codes: H04H 20/42 Arrangements for resource management
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04L 1/0028 Formatting
• CPC Class Codes: H04L 1/0079 Formats for control data H04L1/16 takes precedence; training sequences H04L25/00 and H04L27/00
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 1/1829 Arrangements specially adapted for the receiver end
• CPC Class Codes: H04W 40/00 Communication routing or communication path finding

Abstract

In a communication system comprising a control station (101) and a plurality of dependent stations (102, . . . , 105), the control station (101) broadcasts data intended for the plurality of dependent stations (102, . . . , 105) on a per-superframe basis. The plurality of dependent stations relay the data, which has been received from the control station (101), among themselves. If a dependent station (102) has received the data transmitted from the control station (101), this dependent station (102) transmits an acknowledgement response. If a dependent station (102) does not receive an acknowledgement response from another dependent station (103), then this dependent station (102) relays the data intended for this other dependent station (103).

Claims

1. A communication system in which a control station broadcasts data is intended for a plurality of dependent stations, on a per-superframe basis, each of the plurality of dependent stations comprising:

a receiving unit that receives data broadcast from the control station in an Nth (where N is an integer) superframe;

a transmitting unit that transmits an acknowledgement response that indicates a reception condition of the data, in a time slot that has been allocated to the dependent station in the Nth superframe; and

a relaying unit that relays, in accordance with the an acknowledgement response transmitted from another dependent station, data intended for the other dependent station in a time slot that has been allocated to the dependent station in an (N+1)th superframe.

2. The system according to claim 1, wherein, in a case where an acknowledgement response indicating that data from the control station was received correctly is not received from another dependent station, data intended for the other dependent station is relayed.

3. The system according to claim 1, wherein, in a case where an acknowledgement response indicating that data from the control station was not received correctly was received from another dependent station, data intended for the other dependent station is relayed.

4. The system according to claim 1, wherein, in a case where each of the plurality of dependent stations does not relay data intended for another dependent station, the dependent station transmits other data in a time period that has been reserved for a relay in a time slot that has been allocated to the dependent station.

5. The system according to claim 1, wherein the control station comprises a detecting unit that detects a time period that is not being used, the time period having been reserved, in order that each dependent station may relay data intended for another dependent station;

wherein other data is transmitted in the detected time period.

6. The system according to claim 1, wherein each of the plurality of dependent stations transmits the acknowledgement response and relayed data in one frame.

7. The system according to claim 1, wherein data broadcast from the control station and relayed among the plurality of dependent stations is synchronous data.

8. A dependent station of a communication system in which a control station broadcasts data is intended for a plurality of dependent stations, on a per-superframe basis, the dependent station comprising:

a receiving unit that receives data broadcast from the control station in an Nth (where N is an integer) superframe;

a transmitting unit that transmits an acknowledgement response that indicates a reception condition of the data, in a time slot that has been allocated to the dependent station in the Nth superframe; and

a relaying unit that relays, in accordance with an acknowledgement response transmitted from another dependent station, data intended for the other dependent station in a time slot that has been allocated to the dependent station in an (N+1)th superframe.

11. The dependent station according to claim 8, wherein, in a case where an acknowledgement response indicating that data from the control station was received correctly is not received from another dependent station, data intended for the other dependent station is relayed.

12. The station according to claim 8, wherein, in a case where an acknowledgement response indicating that data from the control station was not received correctly was received from another dependent station, data intended for the other dependent station is relayed.

13. The dependent station according to claim 8, wherein, in a case where each of the plurality of dependent stations does not relay data intended for another dependent station, the dependent station transmits other data in a time period that has been reserved for relaying in a time slot that has been allocated to the dependent station.

14. The dependent station according to claim 8,

wherein the control station includes a detecting unit that detects a time period that is not being used, the time period having been reserved, in order that each dependent station may relay data intended for another dependent station, and

wherein other data is transmitted in the detected time period.

9. A method of relay transmission by a dependent station in a communication system in which a control station broadcasts data intended for a plurality of dependent stations, on a per-superframe basis, the method comprising:

receiving data broadcast from the control station in an Nth (where N is an integer) superframe;

transmitting an acknowledgement response that indicates a reception condition of the data, in a time slot that has been allocated to the dependent station in the Nth superframe; and

in accordance with an acknowledgement response transmitted from another dependent station, relaying data intended for the other dependent station in a time slot that has been allocated to the dependent station in an (N+1)th superframe.

10. A non-transitory computer-readable recording medium storing a program for causing a computer to perform the method set forth in claim 9.