LOW POWER SYNCHRONIZATION IN A WIRELESS COMMUNICATION NETWORK

• US 20160150474A1
• Filed: 07/07/2015
• Published: 05/26/2016
• Est. Priority Date: 11/21/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Ang, Peter Pui Lok, Soriaga, Joseph Binamira, JI, Tingfang, Burke, Joseph Patrick, Shellhammer, Stephen Jay, Mukkavilli, Krishna Kiran, Smee, John Edward
• Granted Patent: US 9,763,189 B2
• Time in Patent Office: Days
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0293 having a sub-controller with a low clock frequency switching on and off a main controller with a high clock frequency
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Some aspects of the present disclosure provide for methods, apparatus, and computer software for low-power synchronization of wireless communication devices. In one example, an asynchronous code division multiple access (CDMA) channel may be utilized for uplink communication. By utilizing asynchronous CDMA on the uplink, synchronization requirements are relaxed relative to other forms of communication. Accordingly, a synchronization period after coming out of a sleep state can be short, reducing power consumption during re-synchronization. In another example, a low-power companion receiver, rather than the full-power WWAN receiver, may be utilized to acquire a sync signal while the device is in its sleep state. Once synchronism is achieved via the low-power companion receiver, the full-power radio may power up and perform communication with the network. By shifting the synchronization from the full-power radio to the low-power companion radio, power consumption during re-synchronization can be achieved.

Claims

1. A method of wireless communication operable at a wireless communication device, comprising:

while a first transmitter and/or first receiver is in a sleep state, waking a second receiver for a synchronization period to listen for a synchronization signal from a wireless network, wherein the second receiver is configured to utilize less power to receive than the first receiver;

receiving the synchronization signal with the second receiver;

establishing synchronism with the wireless network in accordance with the synchronization signal; and

waking the first transmitter and/or receiver from the sleep state to communicate with the wireless network.

2. The method of claim 1, wherein the synchronization signal is of a waveform the first receiver is configured to be capable of receiving and demodulating.

3. The method of claim 2, further comprising:

determining whether to utilize the second receiver for receiving the synchronization signal in accordance with a determination whether the second receiver would perform more poorly than the first receiver according to network conditions, or in accordance with a determination whether timing drift is predicted to be below a predetermined threshold.

4. The method of claim 1, wherein the synchronization signal is a waveform dedicated for the second receiver, of a type different than those waveforms the first receiver is configured to be capable of receiving and demodulating.

5. The method of claim 4, wherein the second receiver is a super-regenerative receiver.

6. The method of claim 4, wherein the first transmitter and/or first receiver is configured for operation in a first radio access technology (RAT), and wherein the second receiver is configured for operation in a second RAT different than the first RAT.

7. The method of claim 1, wherein the waking of the second receiver further comprises waking the second receiver at a time corresponding to a predicted timing of the synchronization signal, and a timing uncertainty of the predicted timing.

8. The method of claim 1, wherein the synchronization signal is periodic having a synchronization signal period, and wherein the synchronization period has a duration at least as long as one synchronization signal period.

9. The method of claim 1, further comprising:

receiving downlink data utilizing the first receiver; and

returning the first receiver to the sleep state.

10. The method of claim 9, further comprising:

utilizing the second receiver to monitor for a paging signal from the wireless network; and

utilizing the second receiver to receive the paging signal.

11. The method of claim 10, wherein the paging signal comprises a page indicator, and wherein the downlink data comprises a full page message.

12. The method of claim 11, wherein the downlink data further comprises information on a traffic channel.

13. The method of claim 1, wherein the synchronization period is configured to span a duration of a predicted worst case timing drift between the wireless communication device and a peer node in a peer to peer network.

14. The method of claim 1, further comprising:

transmitting a capability message to the wireless network for indicating a capability of the second receiver for communication with the wireless network.

15. The method of claim 14, wherein the capability message is configured to indicate at least one of

one or more waveforms the second receiver is capable of receiving and decoding;

or

a capability of the second receiver to receive and detect page messages.

16. The method of claim 14, further comprising:

receiving the synchronization signal configured in accordance with the capability message.

17. The method of claim 1, wherein the waking of the second receiver comprises waking the second receiver a plurality of times according to a first schedule unrelated to a second schedule for the waking of the first transmitter and/or receiver from the sleep state to communicate with the wireless network.

18. A wireless communication device, comprising:

means for communicating with a wireless network;

means for receiving a synchronization signal from a wireless network, wherein the means for receiving the synchronization signal is configured to utilize less power to receive than the means for communicating with the wireless network;

while the means for communicating with the wireless network is in a sleep state, means for waking the means for receiving the synchronization signal for a synchronization period to listen for the synchronization signal;

means for establishing synchronism with the wireless network in accordance with the synchronization signal; and

means for waking the means for communicating with the wireless network from the sleep state to communicate with the wireless network.

19. A non-transitory computer-readable medium storing computer executable code, comprising instructions for causing a processor to:

while a first transmitter and/or first receiver is in a sleep state, wake a second receiver for a synchronization period to listen for a synchronization signal from a wireless network, wherein the second receiver is configured to utilize less power to receive than the first receiver;

receive the synchronization signal with the second receiver;

establish synchronism with the wireless network in accordance with the synchronization signal; and

wake the first transmitter and/or receiver from the sleep state to communicate with the wireless network.

20. A wireless communication device, comprising:

a memory;

a first transmitter and/or a first receiver;

a second receiver for receiving a synchronization signal from a wireless network, wherein the second receiver is configured to utilize less power to receive than the first transmitter and/or first receiver; and

at least one processor communicatively coupled to the memory, the first transmitter and/or first receiver, and the second receiver,

wherein the at least one processor and the memory are configured to;

while the first transmitter and/or first receiver is in a sleep state, wake the second receiver for a synchronization period to listen for the synchronization signal from the wireless network;

receive the synchronization signal with the second receiver;

establish synchronism with the wireless network in accordance with the synchronization signal; and

wake the first transmitter and/or receiver from the sleep state to communicate with the wireless network.

21. The wireless communication device of claim 20, wherein the synchronization signal is of a waveform the first receiver is configured to be capable of receiving and demodulating, and wherein the at least one processor and the memory are further configured to:

determine whether to utilize the second receiver for receiving the synchronization signal in accordance with a determination whether the second receiver would perform more poorly than the first receiver according to network conditions, or in accordance with a determination whether timing drift is predicted to be below a predetermined threshold.

22. The wireless communication device of claim 20, wherein the second receiver is a super-regenerative receiver.

23. The wireless communication device of claim 20, wherein the second receiver is further configured for monitoring for and receiving a paging signal from the wireless network.

24. The wireless communication device of claim 23, wherein the paging signal comprises a page indicator, and wherein the first receiver is configured to receive a full page message indicated in the page indicator.

25. The wireless communication device of claim 20, wherein the synchronization period is configured to span a duration of a predicted worst case timing drift between the wireless communication device and a peer node in a peer to peer network.

26. The wireless communication device of claim 20, wherein the at least one processor and the memory are further configured to transmit a capability message to the wireless network for indicating a capability of the second receiver for communication with the wireless network.

27. The wireless communication device of claim 26, wherein the capability message is configured to indicate at least one of

one or more waveforms the second receiver is capable of receiving and decoding;

or

a capability of the second receiver to receive and detect page messages.

28. The wireless communication device of claim 26, wherein the at least one processor and the memory are further configured to receive the synchronization signal configured in accordance with the capability message.

29. The wireless communication device of claim 20, wherein the at least one processor and the memory, being configured to wake the second receiver, are further configured to wake the second receiver a plurality of times according to a first schedule unrelated to a second schedule for the waking of the first transmitter and/or receiver from the sleep state to communicate with the wireless network.