Meshed GPS time synchronized network

• US 10,021,661 B2
• Filed: 11/24/2015
• Issued: 07/10/2018
• Est. Priority Date: 11/24/2015
• Status: Active Grant

• Current Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Original Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Inventors: Shen, Yi, Chen, Ye
• Primary Examiner(s): Rinehart, Mark H
• Assistant Examiner(s): Hunt, Kenneth P
• Application Number:
  US14/950,078
• Publication Number:
  US 20170150463A1
• Time in Patent Office: 959 Days
• Field of Search: 370336, 370350, 455502, 375356, 709248
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A system includes a plurality of base stations coupled in a mesh network. A first base station of the plurality of base stations includes a first antenna to receive a primary timing synchronization signal and a first interface to a wired packet-switched communication link. The first base station is configured to transmit backup timing synchronization information based on the primary timing synchronization signal. A second base station of the plurality of base stations has a second interface to the wired packet-based communication link and is configured to utilize the second timing synchronization signal sent from the first base station responsive to a failure of the primary timing synchronization signal at the second base station.

Claims

1. A method comprising:

a first base station of a plurality of base stations coupled in a mesh network sending a request simultaneously to others of the plurality of base stations coupled to the first base station in the mesh network that backup timing synchronization information be sent from the others of the plurality of base stations to the first base station;

receiving first backup timing synchronization information at the first base station transmitted over a wired packet-switched communication link on the mesh network from a second base station of the others of the plurality of base stations coupled to the first base station in the mesh network responsive to the request;

generating a timing signal in the first base station using the first backup timing synchronization information;

receiving additional backup timing synchronization information at the first base station transmitted over the mesh network from additional base stations of the others of the plurality of base stations; and

the first base station sending a message to the additional base stations that backup timing synchronization information from the additional base stations is no longer needed, the first base station utilizing only the backup timing synchronization information from the second base station to generate the timing signal.

2. The method as recited in claim 1, wherein the first backup timing synchronization information is based on a primary timing synchronization signal the second base station received from a satellite.

3. The method as recited in claim 1, further comprising:

sending the request as a broadcast or multicast to the others of the plurality of base stations; and

sending the request over the wired packet-switched communication link in response to a failure associated with a primary timing synchronization signal of the first base station.

4. The method as recited in claim 1, further comprising the first base station receiving the backup timing synchronization information from all of the others of the plurality of base stations coupled in the mesh network.

5. The method as recited in claim 1, wherein the first and second base stations are base stations for macro cells.

6. The method as recited in claim 1, wherein at least one of the plurality of base stations is for serving small cells.

13. The method as recited in claim 1 further comprising:

a third base station of the plurality of base stations responding to the request with a message indicating that the third base station cannot provide the backup timing synchronization information.

7. A system comprising:

a plurality of base stations coupled in a mesh network;

a first base station of the plurality of base stations, the first base station including a first antenna to receive a primary timing synchronization signal and a first interface to a wired packet-based communication link utilized by the mesh network, the first base station configured to transmit first backup timing synchronization information based on the primary timing synchronization signal responsive to a request from a second base station of the plurality of base stations;

the second base station of the plurality of base stations having a second interface to the wired packet-based communication link and configured to multicast or broadcast the request to others of the plurality of base stations in the mesh network to send backup timing synchronization information responsive to a failure associated with receipt of the primary timing synchronization signal at the second base station; and

the second base station being further configured to utilize the first backup timing synchronization information sent from the first base station to generate a synchronized timing signal in the second base station;

wherein the second base station receives additional backup timing synchronization information transmitted over the mesh network from additional base stations of the others of the plurality of base stations; and

wherein the second base station is configured to send a message to the additional base stations that backup timing synchronization information from the additional base stations is no longer needed to thereby utilize only the backup timing synchronization information from the first base station to generate the synchronized timing signal in the second base station.

8. The system as recited in claim 7, wherein one of the additional base stations is a third base station configured to transmit second backup timing synchronization information based on receipt of the primary timing synchronization signal by the third base station and the request.

9. The system as recited in claim 8 wherein the first, second, and third base stations provide radio coverage for respective first, second, and third macro cells.

10. The system as recited in claim 7 wherein the first base station provides radio coverage for a small cell.

11. A system comprising:

a plurality of base stations coupled in a mesh network; and

a first and second antenna associated respectively with a first base station and a second base station of the plurality of base stations to receive a primary timing synchronization signal;

wherein the first and second base stations of the plurality of base stations broadcast or multicast first and second backup timing synchronization information, respectively, based on the primary timing synchronization signal, over the mesh network on a periodic basis without a request for backup timing synchronization information from another of the plurality of base stations; and

wherein a frequency of the broadcast or multicast of the first and second backup timing synchronization information over the mesh network varies dynamically according to a size of the mesh network and network bandwidth.

12. The system as recited in claim 11 wherein the mesh network utilizes a packet switched wired communication link coupled to each of the plurality of base stations.