Automating radio enablement to facilitate power saving

• US 8,811,247 B2
• Filed: 06/25/2010
• Issued: 08/19/2014
• Est. Priority Date: 06/25/2010
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Thomson, Allan, Torres, Esteban
• Primary Examiner(s): Hsu, Alpus H
• Assistant Examiner(s): DIVITO, WALTER J
• Application Number:
  US12/823,546
• Publication Number:
  US 20110317600A1
• Time in Patent Office: 1,516 Days
• Field of Search: 370/311, 370/313, 370/390, 370/432, 370/338, 340/7.32, 340/7.33, 340/7.35, 340/7.36, 340/5.8, 455/522, 455/343.1, 455/343.2, 455/410, 455/411, 713160- 62, 713/163, 713/176, 713/190, 713/324, 726/3
• US Class Current: 370/311
• CPC Class Codes: H04B 1/005 adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
• CPC Class Codes: H04L 12/12 Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In an example embodiment, there is disclosed herein an apparatus comprising a wireless transceiver and a controller coupled to the wireless transceiver and configured to receive data via the wireless transceiver. The controller operates the wireless transceiver at a first power save state where the wireless transceiver can receive a frame but other circuits are de-energized. The controller is responsive to the wireless transceiver receiving a frame while the wireless transceiver is in a first power state to determine whether the frame is a predefined wakeup frame. The controller provides additional power to the wireless transceiver responsive to determining the frame is a predefined wakeup frame.

Claims

1. A dual communication mode apparatus, comprising:

a first wireless transceiver, the first wireless transceiver comprises a transmitter, a receiver and a decryption circuit, the first wireless transceiver being operable in a first communication mode for communication with an associated first communication network;

a second wireless transceiver operable in a second communication mode different than the first communication mode for communication with an associated second communication network;

a controller coupled with the first and second wireless transceivers and configured to communicate data via the first and second wireless transceivers;

wherein the controller operates the first wireless transceiver in a first power state where the receiver, decryption circuit, and transmitter, are de-energized;

wherein the controller operates the first wireless transceiver in a second power state for repeated predetermined intervals wherein in the second power state power is provided to the receiver for each predetermined interval but the decryption circuit and transmitter are initially de-energized for each predetermined interval;

wherein the controller is responsive to the first wireless transceiver receiving a frame while the wireless transceiver is in the second power state to determine whether the frame is a predefined wakeup frame;

wherein the controller selectively provides power to the receiver and the decryption circuit of the first wireless transceiver with the transmitter being de-energized responsive to determining the frame is a predefined wakeup frame;

wherein the controller determines the frame is the predefined wakeup frame based on an address contained within the frame;

wherein the controller determines, by the decryption circuit decrypting the received frame, whether the frame has a valid signature corresponding to the predefined wakeup frame;

wherein the controller selectively provides power to the receiver, the transmitter, and the decryption circuit of the first wireless transceiver for operative communication with the associated first network responsive to determining that the received frame has the valid signature corresponding to the predefined wakeup frame; and

wherein the controller selectively re-routs traffic of the dual communication mode apparatus initially targeted to the second wireless transceiver for communication via the associated second network to the first wireless transceiver for communication of the traffic with the associated first network while the first wireless transceiver is in operative communication with the associated first network.

2. The apparatus of claim 1, wherein the address of the frame includes a destination address;

and

wherein the controller determines the frame is a predefined wakeup frame by determining whether the destination address of the frame is a predefined multicast destination address.

3. The apparatus of claim 1, wherein the first wireless transceiver is configured to operate on a plurality of wireless channels;

and

wherein the first wireless transceiver operates on a selected one of the plurality of wireless channels to listen for the predefined wakeup frame.

4. The apparatus of claim 1, wherein the controller switches on a transmitter associated with the wireless transceiver responsive to determining the predefined wakeup frame was received;

and

wherein the controller attempts to associate with a network via the first wireless transceiver.

5. The apparatus of claim 4, wherein the controller returns the first wireless transceiver to the second power state for a remainder of the predetermined interval responsive to not successfully associating with the network within a specified time period.

6. The apparatus of claim 1, wherein the controller obtains access point and channel data for at least one access point from the predefined wakeup frame.

7. The apparatus of claim 6, wherein the controller switches the first wireless transceiver to a channel obtained from channel data obtained from the predefined wakeup frame.

8. The apparatus of claim 1, wherein:

the controller is responsive to the first wireless receiver receiving a sequence of frames while the first wireless transceiver is in the second power state to determine whether the sequence of frames are a predefined sequence of wakeup frames; and

,

the controller provides power to the decryption circuit associated with the first wireless transceiver responsive to determining the sequence of frames are the predetermined sequence of wakeup frames.

9. The apparatus of claim 8, wherein the controller determines via the decryption circuit whether each of the received sequence of frames has a valid signature corresponding to a predefined sequence of wakeup frames for one of a group consisting of an access point sending the wakeup frame and a network associated with the access point.

10. The apparatus of claim 9, wherein the controller provides power to a transmit circuit associated with the first wireless transceiver responsive to determining that each of the received sequence of wakeup frames has a signature corresponding to a predefined sequence of wakeup frames.

11. The apparatus of claim 1, wherein the controller provides additional power to the first wireless transceiver responsive to determining a predefined sequence of wakeup frames were received.

12. The apparatus of claim 1, wherein the second wireless transceiver operates while the first wireless transceiver is in a power save mode.

13. A method of operating an associated dual mode device for power savings, the method comprising:

operating a first wireless transceiver in a first communication mode for communication of traffic with an associated first network;

periodically switching a second wireless transceiver between a first power state and a second power state, where the wireless transceiver can receive a frame while in the first power state but not while in the second power state, wherein in the first power state a receiver associated with the second wireless transceiver is energized and operable in a second communication mode different from the first communication mode, and a decryption circuit and a transmitter associated with the second wireless transceiver are each initially de-energized, wherein in the second power state the decryption circuit, the transmitter, and the receiver are each de-energized;

receiving a frame via the second wireless transceiver while in the first power state;

determining whether the frame is a predefined wakeup frame from an associated second network affiliated with the associated first network in communication with the first wireless transceiver;

selectively providing power to the receiver and to the decryption circuit associated with the second wireless transceiver while in the first power state with the transmitter being de-energized responsive to determining the frame is a predefined wakeup frame;

validating a signature in the frame by the decryption circuit;

selectively providing power to the transmitter associated with the second wireless transceiver, to the receiver associated with the second wireless transceiver, and to the decryption circuit associated with the second wireless transceiver while in the first power state responsive to validating the signature in the frame by the decryption circuit;

associating with the associated second network in communication with the second wireless transceiver responsive to validating the signature in the frame; and

re-routing traffic of the associated dual mode device initially targeted to the first wireless transceiver for communication via the associated first network to the second wireless transceiver for communication of the traffic with the associated second network while the second wireless transceiver is in operative communication with the associated second network.

14. The method of claim 13, wherein the determining whether a frame is a predefined wakeup frame comprises determining whether the frame is addressed to a predefined multicast address.

15. The method of claim 13, wherein receiving a frame via the second wireless transceiver while in the first power state further comprises receiving a plurality of frames;

wherein determining whether the frame is a predefined wakeup frame from a network affiliated with a network in communication with the first wireless transceiver further comprises determining whether the plurality of frames contains a predefined sequence of frames; and

wherein providing power to at least one additional circuit associated with the second wireless transceiver is responsive to determining the plurality of frames contained a predefined sequence of frames.

16. A dual communication mode apparatus, comprising:

a first wireless transceiver operable to communicate in a first communication mode with an associated cellular network;

a second wireless transceiver operable to communicate in a second communication mode different than the first communication mode with an associated wireless local area network, the second wireless transceiver comprising a receiver, a decryption circuit, and a transmitter;

a controller operably coupled with the first wireless transceiver and the second wireless transceiver;

wherein the controller periodically switches the second wireless transceiver between a first power state for a predetermined time period and a second power state, wherein in the first power state the receiver is powered, the decryption circuit is initially de-energized, and the transmitter is initially de-energized and the wireless transceiver can receive data, wherein while in the second power state the receiver, decryption circuit, and transmitter are de-energized and the wireless transceiver is unable to receive data;

wherein the controller is responsive to receiving a frame via the second wireless transceiver while in the first power state to determine whether the frame is a predefined wakeup frame;

wherein the controller selectively provides power to the receiver and to the decryption circuit associated with the second wireless transceiver with the transmitter being de-energized responsive to determining the frame is a predefined wakeup frame;

wherein the decryption circuit is operable to validate a signature in the received frame;

wherein the control is operable to selectively provide power to the transmitter associated with the second wireless transceiver, to the receiver associated with the second wireless transceiver, and to the decryption circuit associated with the second wireless transceiver responsive to validating the signature in the received frame by the decryption circuit;

wherein the controller associates with the associated wireless local area network in communication with the second wireless transceiver responsive to validating the signature in the frame; and

wherein the controller is operable to selectively re-route traffic initially targeted to the first wireless transceiver for communication via the associated cellular network instead to the second wireless transceiver for communication via the associated wireless local area network while the second wireless transceiver is associated with the associated wireless local area network.