Synchronized beacon for network having multiple radios

• US 8,169,996 B2
• Filed: 03/28/2006
• Issued: 05/01/2012
• Est. Priority Date: 03/28/2005
• Status: Expired due to Fees

• Current Assignee: Wavestar Communications Systems LLC (Equitable IP Corporation)
• Original Assignee: Sandwave Ip, LLC
• Inventors: Bishop, Donald M.
• Primary Examiner(s): Batista, Marcos
• Application Number:
  US11/392,379
• Publication Number:
  US 20060217138A1
• Time in Patent Office: 2,226 Days
• Field of Search: 370/328, 370/334, 455/502
• US Class Current: 370/350
• CPC Class Codes: H04B 7/2693 Centralised synchronisation, i.e. using external universal time reference, e.g. by using a global positioning system [GPS] or by distributing time reference over the wireline network
• CPC Class Codes: H04W 48/10 using broadcasted information
• CPC Class Codes: H04W 48/12 using downlink control channel
• 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]

Abstract

A network having multiple radios transmits a beacon signal from several radios substantially simultaneously. One embodiment includes a network having a communications backbone that connects several radio transceivers. Another embodiment includes a single station having multiple radio transceivers, which may or may not have directional antennas. Various methods for synchronizing the beacon signals may be used, including transmitting a heartbeat signal along the network so that the beacon signals are broadcast substantially simultaneously.

Claims

1. A network comprising:

a backbone;

a plurality of radio terminals connected to said backbone, each of said plurality of radios being configured to establish at least one two-way data communication session, and configured to delay sending a transmission when another ongoing transmission is detected, at least two of said plurality of radio terminal being located remotely from each other;

a controller connected to said backbone and configured to;

transmit a signal along said backbone to each of said plurality of radio terminals to determine a transmission delay, said transmission delay comprising a time to transmit from said controller to said wireless access point along said network;

determine a maximum transmission delay from said transmission delays;

calculate a beacon delay for each of said plurality of wireless access points using said maximum transmission delay and said transmission delays;

transmit said beacon delay to each of said radio terminals; and

transmit a synchronization signal along said backbone to each of said plurality of radio terminals;

wherein each of said plurality of radio terminals being configured to transmit a beacon signal at the same time and on the same channel.

2. The network of claim 1 wherein each of said plurality of radio terminals has a backbone transmission delay that is calculated by transmitting a calibration message from said controller to each of said plurality of radios.

3. The network of claim 1 wherein said synchronization signal is repeatedly transmitted along said backbone at a predetermined interval.

4. The network of claim 1 wherein said controller comprises a connection to the Internet.

5. The network of claim 1 wherein at least one of said radio terminals comprises a directional antenna.

6. The network of claim 1 wherein a portion of a first coverage area of one of said plurality of radio terminals overlaps a portion of a second coverage area of a second of said plurality of radio terminals.

7. The network of claim 6 wherein each of said plurality of radio terminals is positioned so that each of said plurality of radio terminals can receive a radio transmission from at least one other of said plurality of radio terminals.

8. The network of claim 1 wherein at least one of said radio terminals are mounted on a utility pole.

9. The network of claim 1 wherein at least one of said radio terminals are mounted in a utility pedestal.

10. The network of claim 1 wherein said network further comprises an Internet connection.

11. The network of claim 1 wherein said backbone comprises at least one of a group composed of twisted pair cable, coaxial cable, fiber optic cable, hybrid fiber/coax, and a radio communication path.

12. The network of claim 1 wherein at least one of said plurality of radio terminals is configured to operate in substantial conformance with IEEE 802.11 specification.

13. The network of claim 1 wherein said beacon signal comprises an identifier for a radio transmitter.

14. The network of claim 1 wherein said beacon signal comprises a network identifier.

15. A method comprising:

establishing communications between a controller and a plurality of wireless access points connected on a network;

determining a transmission delay for each of said plurality of wireless access points connected on said network, said transmission delay comprising a time to transmit from said controller to said wireless access points along said network;

determining a maximum transmission delay from said transmission delays;

calculating a beacon delay for each of said plurality of wireless access points using said maximum transmission delay and said transmission delays;

sending a synchronization signal from said controller to said plurality of wireless access points via said network; and

transmitting a beacon signal from each of said plurality of wireless access points at the same time and on the same channel using said heartbeat and said beacon delay for each of said plurality of wireless access points.

16. The method of claim 15 wherein at least one of said wireless access points comprises at least two radio transceivers.

17. The method of claim 15 wherein said synchronization signal is repeatedly transmitted along said network at a predetermined interval.

18. The method of claim 15 wherein said controller comprises a connection to the Internet.

19. The method of claim 15 wherein at least one of said wireless access points comprises a directional antenna.

20. The method of claim 15 wherein a portion of a first coverage area of one of said plurality of wireless access points overlaps a portion of a second coverage area of a second of said plurality of wireless access points.

21. The method of claim 20 wherein each of said plurality of wireless access points is positioned so that each of said plurality of wireless access points can receive a radio transmission from at least one other of said plurality of wireless access points.

22. The method of claim 15 wherein at least one of said wireless access points are mounted on a utility pole.

23. The method of claim 15 wherein at least one of said wireless access points are mounted in a utility pedestal.

24. The method of claim 15 wherein said network further comprises an Internet connection.

25. The method of claim 15 wherein said network comprises at least one of a group composed of twisted pair cable, coaxial cable, fiber optic cable, hybrid fiber/coax, and a radio communication path.

26. The method of claim 15 wherein at least one of said plurality of wireless access points is adapted to operate in substantial conformance with IEEE 802.11 specification.

27. The method of claim 15 wherein said beacon signal comprises an identifier for a radio transmitter.

28. The method of claim 15 wherein said beacon signal comprises a network identifier.