Method and apparatus for cooperative channel switching

• US 9,491,593 B2
• Filed: 08/28/2015
• Issued: 11/08/2016
• Est. Priority Date: 06/07/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Vandwalle, Pierre B., Haque, Tashbeeb, Wolf, Andreas, Balasubramaniyan, Saravanan
• Primary Examiner(s): HAN, CLEMENCE S
• Application Number:
  US14/839,579
• Publication Number:
  US 20160007167A1
• Time in Patent Office: 438 Days
• US Class Current: 1/1
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

An apparatus and methods are provided for opportunistically conducting data communications on multiple wireless channels. In these methods, a device is engaged in data communications with a second device and receives a conflicting communication demand requiring action on one or more channels other than the data-communication channel (e.g., to conduct a channel scan, to issue or receive a beacon). The device arranges a schedule of channel switches to satisfy the communication demand and advises the second device of the schedule, and may explicitly invite the second device to implement the schedule. To the extent the second device does so, the data communications continue on the other channels. The devices may be participating in a synchronized peer-to-peer communication environment that requires their attendance on the data-communication channel and that is not associated with the other channels.

Claims

1. A device for participating in a peer-to-peer network of communication devices, the device comprising:

a processor;

a memory configured to store identifiers of multiple communication channels, including;

a first channel in use by the device to exchange data with a second device in the peer-to-peer network; and

one or more other channels the device must switch to in order to perform a scanning operation that involves scanning the one or more channels; and

a wireless interface for conducting wireless communications;

wherein the processor and the wireless interface are configured to;

exchange data with the second device on the first channel;

switch to the one or more other channels;

conduct the scanning operation on the one or more other channels, wherein the scanning operation includes receiving one or more Probe Response messages or one or more beacon messages;

continue to exchange data with the second device on the one or more other channels; and

synchronize with the second device based at least in part on an availability window, wherein the availability window is extracted from synchronization data from a periodic synchronization frame (PSF), and the PSF is received during a first number of periods on a predetermined social channel from the second device.

2. The device of claim 1,

wherein the scanning operation is separate from the synchronization with the second device.

3. The device of claim 1, wherein the processor and the wireless interface are further configured to:

broadcast, during the availability window, identification data identifying the device in the peer-to-peer network.

4. The device of claim 1, wherein the second device comprises a synchronization station.

5. The device of claim 1, wherein the processor and the wireless interface are further configured to:

receiving, from the second device, a master indication frame (MIF) including information to maintain synchronization between the device and the second device.

6. The device of claim 1, wherein the availability window is characterized by a channel, a time length, and a period of availability.

7. The device of claim 1, wherein the processor and the wireless interface are further configured to:

select the second device for synchronization based at least in part on a selection preference value included in the PSF.

8. A method of synchronizing a first peer device with a second peer device in a peer-to-peer communication network, the method comprising, at the first peer device:

listening on a predetermined social channel for a periodic synchronization frame (PSF) associated with the second peer device;

receiving the PSF on the predetermined social channel from the second peer device;

extracting synchronization data from the PSF, wherein the synchronization data indicates an availability window; and

configure with the first peer device based at least in part on the availability window.

9. The method of claim 8, further comprising:

broadcasting, during the availability window, identification data identifying the first peer device in the peer-to-peer communication network.

10. The method of claim 8, wherein the second peer device is a synchronization station.

11. The method of claim 8, further comprising:

receiving, from the second peer device, a master indication frame (MIF) including information to maintain synchronization between the first peer device and the second peer device.

12. The method of claim 8, wherein the availability window is characterized by a channel, a time length, and a period of availability.

13. The method of claim 8, further comprising:

selecting the second peer device for synchronization based at least in part on a selection preference value included in the PSF.

14. The method of claim 8, wherein the listening is performed for a first number of periods, and the receiving is performed for the first number of periods.

15. A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for synchronizing a first peer device with a second peer device in a peer-to-peer communication network, the method comprising:

receiving a periodic synchronization frame (PSF) on a predetermined social channel from a second peer device;

extracting synchronization data from the PSF, wherein the synchronization data includes an availability window; and

configure the first peer device based at least in part on the availability window.

16. The computer-readable storage medium of claim 15, the method further comprising:

broadcasting, during the availability window, identification data identifying the first peer device in the peer-to-peer communication network.

17. The computer-readable storage medium of claim 15, wherein the second peer device comprises a synchronization station.

18. The computer-readable storage medium of claim 15, the method further comprising:

receiving, from a second peer device, a master indication frame (MIF) including information to maintain synchronization between the first peer device and the second peer device.

19. The computer-readable storage medium of claim 15, wherein the availability window is characterized by a channel, a time length, and a period of availability.

20. The computer-readable storage medium of claim 15, the method further comprising:

selecting the second peer device for synchronization based at least on a selection preference value included in the PSF.