SHORT-RANGE WIRELESS NETWORKS

• US 20120063389A1
• Filed: 02/09/2010
• Published: 03/15/2012
• Est. Priority Date: 03/04/2009
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Abedi, Saied
• Granted Patent: US 9,693,284 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04B 7/15528 Control of operation parameters of a relay station to exploit the physical medium
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04W 40/06 based on characteristics of available antennas
• CPC Class Codes: H04W 40/08 based on transmission power
• CPC Class Codes: H04W 40/12 based on transmission quality or channel quality
• CPC Class Codes: H04W 40/18 based on predicted events

Abstract

A wireless network of devices comprising a relay start device, an intermediate device and a relay end device, information being communicated wirelessly in use between the relay start device and the relay end device via the intermediate device, wherein:

• • the intermediate device comprises control means and transmission means, the control means being operable to cause the intermediate device transmission means to transmit an indication of connection stability as a function of at least one connection stability parameter of the intermediate device.

Claims

1. A wireless network of devices comprising a relay start device, an intermediate device and a relay end device, information being communicated wirelessly in use between the relay start device and the relay end device via the intermediate device, wherein:

the intermediate device comprises control means and transmission means, the control means being operable to cause the intermediate device transmission means to transmit an indication of connection stability as a function of at least one connection stability parameter of the intermediate device.

2. A wireless network device according to claim 1, wherein the indication of stability is one or more bits in a transmission frame, which when set to one or more predetermined values indicate a degree of stability of the intermediate device.

3. A wireless network according to claim 1, in which transmission of information is acknowledged and wherein one stability parameter is the accumulated number of missed acknowledgements of transmission expected, but not received by the intermediate device.

4. A wireless network according to claim 1, wherein the intermediate device further comprises a transmission buffer holding information waiting for transmission and one stability parameter is the amount of information waiting in the transmission buffer.

5. A wireless network according to claim 1, wherein one stability parameter is the number of data packets dropped by the intermediate device.

6. A wireless network according to claim 1, wherein the network comprises decision means operable on receipt of the indication of stability to take it into account to decide whether to transmit a stop or sleep command to the intermediate device, causing it to stop transmission and reception.

7. A wireless network according to claim 6, wherein the decision means takes other factors into account, preferably the availability of an alternative route avoiding the intermediate device and/or the emergency status of ongoing transmission.

8. A wireless network according to claim 6, further comprising reconnection means operable to establish an alternative route avoiding the intermediate device.

9. A wireless network according to claim 8, wherein the alternative route is established using a new transmission pattern diverting from the intermediate device.

10. A wireless network according to claim 8, wherein the reconnection means includes control means in the relay start device and control means in a further device replacing the intermediate device on the route, which are together operable to set up a new connection.

11. A wireless network according to claim 8, wherein the relay start device is operable to transmit the intermediate device identification to the coordinator and the stop command is preferably transmitted from the coordinator to the relay start device.

12. A wireless network according to claim 8, further comprising alarm means operable to alert an outside entity to instability of the intermediate device in dependence upon the indication of stability.

13. An intermediate device for use in a wireless network of devices comprising a relay start device, the intermediate device and a relay end device, information being communicated wirelessly in use between the relays start device and the relay end device via the intermediate device, the intermediate device comprising:

transmission and reception means; and

control means operable to control the device;

wherein

the control means is operable to cause the transmission means to transmit an indication of connection stability as a function of at least one connection stability parameter of the device.

14. A device for use in a wireless network of devices, information being communicated wirelessly in use between the device and at least one other network device, the device comprising:

transmission and reception means; and

control means operable to control the device;

wherein the control means are operable to cause the transmission means to transmit an indication of connection stability as a function of at least one connection stability parameter of the device.

15. A coordinator in a wireless network of devices comprising at least the coordinator, an intermediate device and a relay end device, information being communicated wirelessly in use between the coordinator and the relay end device via the intermediate device, wherein the coordinator comprises:

reception means operable to receive an indication of connection stability of the intermediate device from the intermediate device;

decision means operable on receipt of the indication to take it into account to decide whether to transmit a stop command to the intermediate device, causing it to stop transmission and reception.