Method and apparatus for cooperative channel switching

• US 9,125,236 B2
• Filed: 06/07/2013
• Issued: 09/01/2015
• 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:
  US13/913,278
• Publication Number:
  US 20140362726A1
• Time in Patent Office: 816 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; and

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

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

synchronize with a plurality of peer devices in the peer-to-peer network, including the second device;

wherein the scanning operation is separate from synchronization with the plurality of peer devices.

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

prior to switching to the one or more other channels, broadcast a sequence of channel switches to be conducted by the device;

wherein the sequence of channel switches includes the first channel and the one or more other channels.

4. The device of claim 3, wherein broadcasting the sequence of channel switches comprises:

broadcasting a synchronization frame that identifies the sequence of channel switches and that includes an invitation to the second device to match the channel switches.

5. A method of conducting opportunistic data communications at a first device, the method comprising:

commencing a data exchange with a second device on a first wireless communication channel;

receiving a communication demand, separate from the data exchange, that requires switching to a second wireless communication channel different from the first wireless communication channel;

satisfying the communication demand on the second wireless communication channel; and

continuing the data exchange on the second wireless communication channel.

6. The method of claim 5, further comprising, prior to receiving the communication demand:

synchronizing with a logical hierarchy of peer communication devices that includes the second device; and

implementing a first sequence of channel switches supporting synchronization with the logical hierarchy, wherein the first sequence includes the first wireless communication channel.

7. The method of claim 6, wherein synchronizing with the logical hierarchy comprises:

broadcasting a first periodic synchronization frame that identifies the first sequence of channel switches; and

receiving periodic synchronization frames broadcast by one or more of the peer communication devices.

8. The method of claim 6, further comprising, after receiving the communication demand:

devising a second sequence of channel switches supporting satisfaction of the communication demand; and

broadcasting a periodic synchronization frame configured to;

identify the second sequence of channel switches; and

invite the second device to implement the second sequence of channel switches.

9. The method of claim 5, further comprising, prior to continuing the data exchange:

identifying a sequence of channel switches that includes the first wireless communication channel and the second wireless communication channel; and

informing the second device of the sequence of channel switches;

wherein the second device implements at least a portion of the sequence of channel switches.

10. The method of claim 5, wherein:

the first wireless communication channel is a channel on which multiple devices in a synchronized peer-to-peer network environment rendezvous; and

the second wireless communication channel is a channel that is not used as part of the synchronized peer-to-peer network environment.

11. The method of claim 5, wherein:

the communication demand is a request to conduct a channel scan on one or more wireless communication channels; and

continuing the data exchange includes exchanging data with the second device when not transmitting a probe request or receiving a probe response.

12. The method of claim 5, wherein:

the first wireless communication channel supports a peer-to-peer communication network;

the communication demand includes supporting a first infrastructure communication connection on the second wireless communication channel; and

continuing the data exchange comprises;

alternating between the second wireless communication channel and a third wireless communication channel on which the second device is engaged in an infrastructure communication connection; and

continuing to exchange data with the second device during said alternating.

13. A method of exchanging data within a peer-to-peer communication network, the method comprising, at a first peer device:

synchronizing with multiple peer devices by congregating with the multiple peer devices on a set of rendezvous channels;

implementing a first sequence of wireless channel switches that includes the set of rendezvous channels;

engaging in a transfer of data with a second peer device on at least one of the rendezvous channels;

receiving a communication requirement separate from the peer-to-peer communication network;

scheduling a second sequence of wireless channel switches that includes one or more channels not used by the peer-to-peer communication network;

advising the second peer device of the second sequence of wireless channel switches prior to implementation of the second sequence of wireless channel switches;

implementing the second sequence of wireless channel switches; and

continuing the transfer of data with the second peer device on at least one of the one or more channels.

14. The method of claim 13, further comprising, after satisfaction of the communication requirement:

advising the second peer device of the first sequence of wireless channel switches; and

re-implementing the first sequence of wireless channel switches.

15. The method of claim 13, wherein advising the second peer device of the second sequence of wireless channel switches comprises:

generating a synchronization frame configured to;

identify the second sequence of wireless channel switches; and

invite peer devices, including the second peer device, to implement the second sequence of wireless channel switches; and

broadcasting the synchronization frame on one or more of the rendezvous channels.

16. The method of claim 13, wherein synchronizing with the multiple peer devices comprises:

receiving multiple synchronization frames broadcast by one or more of the multiple peer devices, each said synchronization frame identifying one or more of the rendezvous channels; and

tuning to the rendezvous channels at one or more times specified in the multiple synchronization frames;

wherein the multiple peer devices also tune to the rendezvous channels at the one or more times.

17. The method of claim 13, wherein the communication requirement is one of:

conduct a channel scan; and

support an infrastructure communication connection.

18. The method of claim 13, wherein:

the communication requirement includes transmitting a Probe Request message on a scan channel; and

continuing the transfer of data comprises exchanging data with the second peer device on the scan channel.

19. The method of claim 13, wherein:

the communication requirement includes supporting an infrastructure communication connection; and

continuing the transfer of data comprises exchanging data with the second peer device on a scan channel.

20. The method of claim 13, wherein:

the communication requirement includes supporting a first infrastructure communication connection; and

continuing the transfer of data includes;

alternating between a first infrastructure communication channel associated with the first infrastructure communication connection and a second infrastructure communication channel associated with an infrastructure communication connection of the second peer device; and

continuing the transfer of data on the first infrastructure communication channel and the second infrastructure communication channel.