Method and apparatus for device synchronization and power conservation in a wireless communication system

• US 9,204,409 B2
• Filed: 02/22/2011
• Issued: 12/01/2015
• Est. Priority Date: 02/22/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Bhatia, Ashutosh, Patro, Ranjeet Kumar, Arunan, Thenmozhi
• Primary Examiner(s): Patel, Jay P
• Application Number:
  US13/580,653
• Publication Number:
  US 20130058318A1
• Time in Patent Office: 1,743 Days
• Field of Search: 370/377
• US Class Current: 1/1
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 56/003 Arrangements to increase tolerance to errors in transmission or reception timing
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

The present invention provides a method and apparatus for device synchronization and power conservation in a wireless communication system. In one embodiment, a method of a communication device for device synchronization and conserving power includes determining one or more device parameters in a wireless communication system, where the one or more device parameters are indicative of one or more time slots and at least one additional guard slot required during data transaction. The method also includes forming a connection request including the one or more device parameters, and communicating the connection request to a controller in the wireless communication system. Moreover, the method includes receiving a connection assignment frame including a device allocation interval from the controller based on the one or more device parameters, wherein the device allocation interval includes the one or more time slots and the at least one additional guard slot allocated to the communication device for data transaction.

Claims

1. A method of operating a communication device for device synchronization and power conservation in a wireless communication, the method system comprising:

generating a connection request including one or more device parameters indicative of the one or more time slots and at least one additional guard slot required for data transaction;

communicating the connection request to a controller in the wireless communication system; and

receiving a connection response indicating the one or more time slots and the at least one additional guard slot allocated to the communication device for data transaction based on the one or more device parameters,

wherein at least one of the one or more device parameters is determined based on a remaining battery power of the communication device.

2. The method of claim 1, wherein the one or more device parameters are selected from the group consisting of a clock slew of the communication device with respect to the controller, minimum number of beacons frames to be skipped, a scale up factor, and a scale down factor.

3. The method of claim 2, wherein the scale up factor and the scale down factor are determined based on remaining battery power and packet arrival rate.

4. The method of claim 3, wherein the scale up factor and the scale down factor indicate minimum and maximum values of guard time with respect to the one or more time slots.

5. The method of claim 1, further comprising:

skipping listening of a number of beacons frames to conserve power, wherein the number of beacon frames to be skipped are advertised by the controller in the connection response.

6. A non-transitory computer-readable storage medium having instructions stored therein, that when executed by a communication device, result in performing a method comprising:

generating a connection request including one or more device parameters indicative of the one or more time slots and at least one additional guard slot required for data transaction;

communicating the connection request to a controller in the wireless communication system; and

receiving a connection response indicating the one or more time slots and the at least one additional guard slot allocated to the communication device for data transaction based on the one or more device parameters,

wherein at least one of the one or more device parameters is determined based on a remaining battery power of the communication device.

7. The storage medium of claim 6, wherein the one or more device parameters are selected from the group consisting of a clock slew of the communication device with respect to the controller, minimum number of beacons frames to be skipped during a connection establishment phase, a power saving requirement, a scale up factor, and a scale down factor.

8. The storage medium of claim 7, wherein the scale up factor and the scale down factor are determined based on remaining battery power, packet arrival rate, and expected battery life time.

9. The storage medium of claim 8, wherein the scale up factor and the scale down factor indicate minimum and maximum values of guard time with respect to the one or more time slots.

10. The storage medium of claim 9, wherein the method further comprises:

skipping listening of a number of beacons frames during a connection establishment phase to conserve power, wherein the number of beacon frames are advertised by the controller in the connection response.

11. A communication device comprising:

a processor configured to generate a connection request including one or more device parameters indicative of the one or more time slots and at least one additional guard slot required for data transaction; and

an interface unit configured to communicate the connection request to a controller in a wireless communication system and to receive a connection response indicating the one or more time slots and the at least one additional guard slot allocated for data transaction based on the one or more device parameters,

wherein at least one of the one or more device parameters is determined based on a remaining battery power of the communication device.

12. The device of claim 11, wherein the one or more device parameters are selected from the group consisting of a clock slew of the communication device with respect to the controller, minimum number of beacons frames to be skipped during a connection establishment phase, a power saving requirement, a scale up factor, and a scale down factor.

13. The device of claim 12, wherein the scale up factor and the scale down factor are determined based on the remaining battery power, a packet arrival rate, and an expected battery life time.

14. The device of claim 13, wherein the scale up factor and the scale down factor indicate minimum and maximum values of guard time with respect to the one or more time slots.

15. The device of claim 11, wherein the processor is configured to skip listening of a number of beacons frames to conserve power, wherein the number of beacon frames are advertised by the controller in the connection response.

16. A method of a controller for allocating time slots in a medium access control (MAC) superframe to a communication device in a wireless communication system, the method comprising:

receiving a connection request from the communication device for establishment of a connection with the controller, wherein the connection request includes device parameters indicative of number of time slots and additional guard slots required for data transaction;

configuring the number of time slots and the additional guard slots in a MAC superframe based on the device parameters in the connection request; and

transmitting a connection response indicating the number of time slots and the additional guard slots allocated to the communication device based on the device parameters,

wherein at least one of the one or more device parameters is determined based on a remaining battery power of the communication device.

17. The method of claim 16, wherein receiving the connection request from the communication device for establishment of the connection with the controller further comprises:

sending an acknowledgement frame to the communication device in response to the connection request.

18. The method of claim 16, wherein configuring the number of time slots and the additional guard slots in the MAC superframe based on the device parameters in the connection request comprises:

determining whether there are unallocated time slots equal to the number of time slots and the additional guard slots in the MAC superframe;

if so, allocating the unallocated time slots in the MAC superframe to the communication device;

if not, determining whether there are any time slots in the MAC superframe allocated to one or more communication devices, wherein the one or more communication devices are having a lower priority than the communication device;

if so, unallocating the allocated time slots from the MAC superframe and allocating the unallocated time slots to the communication device; and

if not, rejecting the connection request received from the communication device.

19. The method of claim 18, wherein unallocating the allocated time slots from the MAC superframe and reallocating the unallocated time slots to the communication device comprises:

reallocating one or more unallocated time slots in the MAC superframe to the one or more communication devices; and

transmitting a connection response indicating reallocation of the time slots in the MAC superframe to the one or more communication devices.

20. The method of claim 19, wherein the scale up factor and the scale down factor are determined based on the remaining battery power, a packet arrival rate, and an expected battery life time.

21. The method of claim 16, wherein the device parameters are selected from the group consisting of clock slew of the communication device with respect to the controller, minimum number of beacons frames to be skipped, power saving information, a scale up factor, and a scale down factor.

22. The method of claim 16, further comprising:

periodically determining a maximum number of beacon frames that the communication device can skip to listen based on a current network load; and

advertising the maximum number of beacon frames allowed to skip to the communication device.

23. A non-transitory computer-readable storage medium having instructions stored therein for allocating time slots in a medium access control (MAC) superframe to a communication device in a wireless communication system, that when executed by a controller, result in performing a method comprising:

receiving a connection request from the communication device for establishment of a connection with the controller, wherein the connection request includes device parameters indicative of number of time slots and additional guard slots required for data transaction;

configuring the number of time slots and the additional guard slots in a MAC superframe based on the device parameters in the connection request; and

transmitting a connection response indicating the number of time slots and the additional guard slots allocated to the communication device based on the device parameters,

wherein at least one of the one or more device parameters is determined based on a remaining battery power of the communication device.

24. The storage medium of claim 23, wherein the instructions to receive the connection request from the communication device for establishment of the connection with the controller further comprises:

sending an acknowledgement frame to the communication device in response to the connection request.

25. The storage medium of claim 23, wherein the instructions to configure the number of time slots and the additional guard slots in the MAC superframe based on the device parameters in the connection request comprises:

determining whether there are unallocated time slots equal to the number of time slots and the additional guard slots in the MAC superframe;

if so, allocating the unallocated time slots in the MAC superframe to the communication device;

if not, determining whether there are any time slots in the MAC superframe allocated to one or more communication devices, wherein the one or more communication devices are having a lower priority than the communication device;

if so, unallocating the allocated time slots from the MAC superframe and allocating the unallocated time slots to the communication device; and

if not, rejecting the connection request received from the communication device.

26. The storage medium of claim 25, wherein the instructions to unallocate the allocated time slots from the MAC superframe and reallocating the unallocated time slots to the communication device comprises:

reallocating one or more unallocated time slots in the MAC superframe to the one or more communication devices; and

transmitting a connection response indicating reallocation of the time slots in the MAC superframe to the one or more communication devices.

27. The storage medium of claim 23, wherein the device parameters are selected from the group consisting of clock slew of the communication device with respect to the controller, minimum number of beacons frames to be skipped, power saving information, a scale up factor, and a scale down factor.

28. The storage medium of claim 27, wherein the scale up factor and the scale down factor are determined based on remaining battery power, packet arrival rate, and expected battery life time.

29. The storage medium of claim 23, wherein the method further comprises:

periodically determining a maximum number of beacon frames that the communication device can skip to listen based on a current network load; and

advertising the maximum number of beacon frames allowed to skip during the connection establishment phase to the communication device.

30. A controller comprising:

an interface unit configured to receive a connection request from a communication device for establishment of a connection with the controller, wherein the connection request includes device parameters indicative of number of time slots and additional guard slots required for data transaction; and

a processor configured to configure the number of time slots and the additional guard slots in a MAC superframe based on the device parameters in the connection request,

wherein the interface unit is configured to transmit a connection response indicating the number of time slots and the additional guard slots allocated to the communication device based on the device parameters,

wherein at least one of the one or more device parameters is determined based on a remaining battery power of the communication device.

31. The controller of claim 30, wherein the interface unit is configured to send an acknowledgement frame to the communication device in response to the connection request.

32. The controller of claim 30, wherein the processor is configured to:

determine whether there are unallocated time slots equal to the number of time slots and the additional guard slots in the MAC superframe;

if so, allocate the unallocated time slots in the MAC superframe to the communication device;

if not, determine whether there are any time slots in the MAC superframe allocated to one or more communication devices, wherein the one or more communication devices are having a lower priority than the communication device;

if so, unallocate the allocated time slots from the MAC superframe and allocating the unallocated time slots to the communication device; and

if not, reject the connection request received from the communication device.

33. The controller of claim 32, wherein the processor is configured to reallocate one or more unallocated time slots in the MAC superframe to the one or more communication devices,

wherein the interface unit is configured to transmit a connection response indicating reallocation of the time slots in the MAC superframe to the one or more communication devices.

34. The controller of claim 30, wherein the device parameters are selected from the group consisting of clock slew of the communication device with respect to the controller, minimum number of beacons frames to be skipped, power saving information, a scale up factor, and a scale down factor.

35. The controller of claim 34, wherein the scale up factor and the scale down factor are determined based on the remaining battery power, a packet arrival rate, and an expected battery life time.

36. The controller of claim 30, wherein the processor is configured to periodically determine a maximum number of beacon frames that the communication device can skip to listen based on a current network load,

wherein the interface unit is configured to advertise the maximum number of beacon frames allowed to skip to the communication device.

37. A method of a communication device for device synchronization in a wireless communication, the method system comprising:

transmitting a connection request including one or more device parameters indicative of feature of the communication device to a controller in the wireless communication system; and

receiving a connection response indicating one or more time slots and at least one additional guard slot allocated to the communication device for data transaction based on the one or more device parameters,

wherein at least one of the one or more device parameters is determined based on a remaining battery power of the communication device.

38. The method of claim 37, wherein the feature of the communication device comprises remaining battery power of the communication device.