Apparatus, method and implementation for adaptable wireless beacon communication system

• US 8,804,590 B2
• Filed: 12/13/2011
• Issued: 08/12/2014
• Est. Priority Date: 12/20/2010
• Status: Expired due to Fees

• Current Assignee: Sovereign Peak Ventures, LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Nakae, Hironori, Ukita, Yosuke, Hayashino, Hiroshi
• Primary Examiner(s): Jiang, Charles C
• Assistant Examiner(s): CLARK, ROSENE S
• Application Number:
  US13/577,724
• Publication Number:
  US 20120307702A1
• Time in Patent Office: 973 Days
• Field of Search: 370/321, 370/330, 370/338, 370/348, 370/311, 455/509, 709/225
• US Class Current: 370/311
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

Provided is a communication apparatus which allows multi-rate control causing less waste of communication band as compared to conventional, the communication apparatus according to the present invention includes: the wireless communication unit for performing wireless communication with the terminal apparatus; a transfer rate setting unit for setting a transfer rate; a beacon generation unit for generating a beacon which is a first control signal; and a control unit for causing the wireless communication unit to wirelessly transmit, for every predetermined period, the beacon, and, to cause the wireless communication unit to wirelessly transmit the beacon, the control unit causes the transfer rate setting unit to set a transfer rate different from the transfer rate previously used for the wireless transmission of the beacon, and causes the wireless communication unit to transmit the beacon to the terminal apparatus.

Claims

1. A communication apparatus comprising:

a wireless communication device configured to perform wireless communication with one or more terminal apparatuses;

a transfer rate setting device configured to set a transfer rate of the wireless communication performed by the wireless communication device;

a beacon generation device configured to generate a beacon which specifies a first period in association with a first transfer rate and a second period in association with a second transfer rate lower than the first transfer rate; and

a control device configured to cause the wireless communication device to wirelessly transmit, for every predetermined period, the beacon generated by the beacon generation device,

wherein when causing the wireless communication device to wirelessly transmit the beacon, the control device is configured to cause the transfer rate setting device to set the transfer rate different from a transfer rate previously used for wirelessly transmitting the beacon and cause the wireless communication device to transmit the beacon to the one or more terminal apparatuses, and

wherein, when the wireless communication device fails to transmit a data signal at the first transfer rate in the first period, the control device is configured to cause the wireless communication device to retransmit the data signal at the second transfer rate in the second period.

2. The communication apparatus according to claim 1,

wherein the control device is configured to

cause the transfer rate setting device to set the transfer rate to the first transfer rate when causing the wireless communication device to wirelessly transmit the beacon in the first period, and

cause the transfer rate setting device to set the transfer rate to the second transfer rate when causing the wireless communication device to wirelessly transmit the beacon in the second period.

3. The communication apparatus according to claim 2,

wherein the beacon further specifies a first time which is a time within the first period, and

if an error rate which is a value corresponding to a number of times for which the wireless communication device has failed to wirelessly receive a data signal is greater than or equal to a predetermined first threshold value at the first time, the control device is configured to (A) cause the transfer rate setting device to set the transfer rate to the second transfer rate and (B) cause the wireless communication device to wirelessly transmit, to all of the one or more terminal apparatuses, a second control signal for setting a transfer rate of the one or more terminal apparatuses to the second transfer rate.

4. The communication apparatus according to claim 3,

wherein the beacon further specifies a second time which is a time within the first period and later than the first time, and

when the error rate is less than the predetermined first threshold value at the first time and if the error rate is greater than or equal to a predetermined second threshold value at the second time, the control device is configured to cause the transfer rate setting device to set the transfer rate to the second transfer rate and cause the wireless communication device to wirelessly transmit, to all of the one or more terminal apparatuses, the second control signal for setting the transfer rate of the one or more terminal apparatuses to the second transfer rate.

5. The communication apparatus according to claim 3, wherein the control device is configured to transmit a data signal earlier in time to one of the one or more terminal apparatuses from which the data signal is transmitted which has the larger received power when received by the wireless communication device.

6. The communication apparatus according to claim 2,

wherein the beacon further specifies a first time which is a time within the first period,

if an error rate which is a value corresponding to a number of times for which the wireless communication device has failed to wirelessly receive a data signal is greater than or equal to a predetermined first threshold value at the first time, the control device is configured to cause the wireless communication device to wirelessly transmit, to all of the one or more terminal apparatuses, a second control signal which includes a second time and is a control signal for keeping a transfer rate of the one or more terminal apparatuses at the first transfer rate until the second time which is a time within the second period, and

the first transfer rate has a smaller value of the transfer rate than the second transfer rate.

7. The communication apparatus according to claim 2, wherein the control device is configured to cause the beacon generation device to generate the beacon such that, among a total number of terminal apparatuses, the smaller a number of terminal apparatuses that receive the beacon wirelessly transmitted at the first transfer rate is relative to a number of terminal apparatuses that receive the beacon wirelessly transmitted at the second transfer rate, the shorter the first period is relative to the second period.

8. The communication apparatus according to claim 2, wherein the control device is configured to cause the beacon generation device to generate the beacon such that (A) among a total number of terminal apparatuses, the smaller a number of terminal apparatuses that receive the beacon wirelessly transmitted at the first transfer rate is relative to a number of terminal apparatuses that receive the beacon wirelessly transmitted at the second transfer rate and (B) the higher the first transfer rate is relative to the second transfer rate, the shorter the first period is relative to the second period.

9. The communication apparatus according to claim 1,

wherein the beacon further specifies a third period and a third transfer rate which is the transfer rate in association with the third period and different from the first transfer rate and the second transfer rate, and

the control device is configured to

cause the transfer rate setting device to set the transfer rate to the first transfer rate to cause the wireless communication device to wirelessly transmit the beacon in the first period,

cause the transfer rate setting device to set the transfer rate to the second transfer rate to cause the wireless communication device to wirelessly transmit the beacon in the second period, and

cause the transfer rate setting device to set the transfer rate to the third transfer rate to cause the wireless communication device to wirelessly transmit the beacon in the third period.

17. A communication system comprising the communication apparatus according to claim 1 and a terminal apparatus having a wireless communication device,

wherein the wireless communication device included in the terminal apparatus is configured to receive, among beacons, a beacon that is transmitted from the communication apparatus at a transfer rate receivable by the wireless communication device of the terminal apparatus.

10. A terminal apparatus comprising:

a wireless communication device which can perform wireless communication with a communication apparatus;

a transfer rate setting device configured to set, from among a plurality of transfer rates, a transfer rate which is used by the wireless communication device for the wireless communication; and

a control device configured to cause the transfer rate setting device to set the transfer rate, based on a beacon received by the wireless communication device,

wherein the beacon specifies a first period in association with a first transfer rate and a second period in association with a second transfer rate, and

wherein, when the wireless communication device fails to transmit a data signal at the first transfer rate in the first period, the control device is configured to cause the wireless communication device to retransmit the data signal at the second transfer rate in the second period.

11. The terminal apparatus according to claim 10,

wherein the beacon further specifies a first time which is a time within the first period, and

the control device is configured

to cause the transfer rate setting device to set, at the first time, the transfer rate to the second transfer rate, and determines whether the wireless communication device has received a second control signal at the second transfer rate,

to cause the transfer rate setting device to set the transfer rate to the first transfer rate when the second control signal has not been received, and

not to cause the transfer rate setting device to change the transfer rate when the second control signal has been received.

12. The terminal apparatus according to claim 10, wherein when the wireless communication device fails to wirelessly transmit a data signal at the first transfer rate greater than or equal to a predetermined number of times in the first period, the control device is configured to cause the wireless communication device to retransmit, in the second period, the data signal at the second transfer rate.

13. The terminal apparatus according to claim 10, wherein prior to causing the wireless communication device to perform wireless transmission, the control device is configured to perform carrier sensing which is a process of determining whether other another terminal apparatus is performing wireless transmission, and if it is determined that no other terminal apparatus is performing the wireless transmission, the control device is configured to determine a backoff time, which is a wait time until when the control device causes the wireless communication device to perform the wireless transmission after the carrier sensing is performed, such that as a received power of the beacon decreases the backoff time increases, and after the backoff time is passed, the control device is configured to cause the wireless communication device to perform the wireless transmission.

14. A communication method comprising:

generating a beacon which specifies a first period in association with a first transfer rate and a second period in association with a second transfer rate lower than the first transfer rate;

instructing a wireless communication device to wirelessly transmit the generated beacon for every predetermined period; and

setting a transfer rate, which is used by the wireless communication device for wirelessly transmitting the beacon, to a transfer rate different from a transfer rate previously used for wirelessly transmitting the beacon,

wherein, when the wireless communication device fails to transmit a data signal at the first transfer rate in the first period, said instructing of the wireless communication device instructs the wireless communication device to retransmit the data signal at the second transfer rate in the second period.

15. A non-transitory computer-readable recording medium having a computer program recorded thereon, the computer program causing a computer to execute the communication method according to claim 14.

16. An integrated circuit comprising:

a wireless communication device configured to perform wireless communication with one or more terminal apparatuses;

a transfer rate setting device configured to set a transfer rate of the wireless communication performed by the wireless communication device;

a beacon generation device configured to generate a beacon which specifies a first period in association with a first transfer rate and a second period in association with a second transfer rate lower than the first transfer rate; and

a control device configured to cause the wireless communication device to wirelessly transmit, for every predetermined period, the beacon generated by the beacon generation device,

wherein when causing the wireless communication device to wirelessly transmit the beacon, the control device is configured to cause the transfer rate setting device to set a transfer rate different from a transfer rate previously used for wirelessly transmitting the beacon, and cause the wireless communication device to transmit the beacon to the one or more terminal apparatuses, and

wherein, when the wireless communication device fails to transmit a data signal at the first transfer rate in the first period, the control device is configured to cause the wireless communication device to retransmit the data signal at the second transfer rate in the second period.