Reduced terminal power consumption via use of active hold state

• US 8,689,025 B2
• Filed: 02/20/2007
• Issued: 04/01/2014
• Est. Priority Date: 02/21/2006
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Attar, Rashid Ahmed Akbar, Bhushan, Naga, Au, Jean Put Ling
• Primary Examiner(s): WANG, ALBERT C
• Application Number:
  US11/676,902
• Publication Number:
  US 20070195723A1
• Time in Patent Office: 2,597 Days
• Field of Search: 370/468, 370/311, 455/574, 455/343.2, 713/320
• US Class Current: 713/320
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

An access terminal (AT) in a cellular communication system is configured to operate in an active hold (AH) state, a transitional state between traffic and dormant states. The AT applies power to its transmit chain with a low duty cycle while in the AH state, conserving battery power. To improve robustness of the communications, the radio network may power control the AT to a higher level relative to the power control level of the AT in the traffic state. Transition from the traffic state to the AH state may be initiated after a brief period of inactivity on the reverse link. The AT may remain in the AH state while receiving forward link payload data. Transmission of a reverse link payload packet in the AH state may initiate transition to the traffic state. A prolonged period of inactivity may initiate a transition from the AH state to the dormant state.

Claims

1. A wireless access terminal for communicating with a base transceiver station of a radio network, the wireless access terminal comprising:

a transmitter configured to send reverse link transmissions to the base transceiver station; and

a controller coupled to the transmitter, wherein the controller is configured to execute program code to cause the wireless access terminal to;

initiate transitions between a traffic state, a dormant state, and an active hold state, wherein the transitions between the traffic state and the active hold state are initiated by sending a codeword on a reverse rate indicator (RRI) channel,

receive an indication of whether the radio network has granted the transitions on an acknowledgement (ACK) channel, and

power off at least one component of the transmitter in the active hold state so that a duty cycle of said at least one component is less than a predetermined duty cycle threshold in the active hold state.

2. The wireless access terminal of claim 1, wherein the controller is further configured to execute the program code to cause the wireless access terminal to power on said at least one component of the transmitter for at least a majority of time in the traffic state.

3. The wireless access terminal of claim 2, wherein the controller is further configured to execute the program code to cause the wireless access terminal to provide feedback to the base transceiver station with a first frequency in the active hold state, and to provide feedback to the base transceiver station with a second frequency in the traffic state, the second frequency being greater than the first frequency.

4. The wireless access terminal of claim 3, wherein the second frequency is twice the first frequency.

5. The wireless access terminal of claim 3, wherein the second frequency is four times the first frequency.

6. The wireless access terminal of claim 3, wherein the feedback comprises reverse link pilot and forward link rate control.

7. The wireless access terminal of claim 2, wherein the controller is further configured to execute the program code to cause the wireless access terminal to provide feedback to the base transceiver station once in eight slots in the active hold state, and to provide feedback to the base transceiver station once in four slots in the traffic state.

8. The wireless access terminal of claim 2, wherein the controller is further configured to execute the program code to cause the wireless access terminal to provide feedback to the base transceiver station once in sixteen slots in the active hold state, and to provide feedback to the base transceiver station once in four slots in the traffic state.

9. The wireless access terminal of claim 1, wherein the controller is further configured to execute the program code to cause the wireless access terminal to transition from the dormant state to the active hold state in response to simultaneous presence of forward link traffic and absence of reverse link traffic.

10. The wireless access terminal of claim 1, further comprising:

a receiver configured to receive forward link transmissions from the base transceiver station,

wherein the controller configured to execute program code to cause the wireless access terminal to initiate transitions between a traffic state, a dormant state, and an active hold state is configured to;

initiate a transition from the traffic state to the active hold state in response to absence of reverse link traffic during a first predetermined time period,

initiate a transition from the active hold state to the traffic state in response to presence of reverse link traffic,

initiate a transition from the active hold state to the dormant state in response to absence of forward link traffic and reverse link traffic during a second predetermined period,

initiate a transition from the dormant state to the traffic state in response to presence of reverse link traffic, and

remain in the active hold state after transitioning into the active hold state during simultaneous presence of forward link traffic and absence of reverse link traffic.

11. The wireless access terminal of claim 1, wherein the predetermined duty cycle threshold is less than fifty percent.

12. The method of claim 1, wherein the codeword on the RRI channel comprises a spare codeword on the RRI channel, wherein the spare codeword is otherwise unused at the radio network.

13. A non-transitory machine-readable medium comprising instructions that, when executed by at least one processor of a wireless access terminal for communicating with a base transceiver station of a radio network, cause the wireless access terminal to perform operations comprising:

initiating transitions between a traffic state, a dormant state, and an active hold state, wherein the transitions between the traffic state and the active hold state are initiated by sending a codeword on the reverse rate indicator (RRI) channel;

receiving an indication of whether the radio network has granted the transitions on an acknowledgement (ACK) channel; and

in the active hold state, powering off at least one component of a transmitter of the access terminal so that a duty cycle of said at least one component is less than a predetermined duty cycle threshold in the active hold state.

14. The machine-readable medium of claim 13, wherein the instructions, when executed by said at least one processor, further cause the wireless access terminal to perform operations comprising:

powering on said at least one component of the transmitter for at least a majority of time in the traffic state.

15. The machine-readable medium of claim 14, wherein the instructions, when executed by said at least one processor, further cause the wireless access terminal to perform operations comprising:

providing feedback to the base transceiver station in the active hold state, the step of providing feedback in the active hold state being performed with a first frequency; and

providing feedback to the base transceiver station in the traffic state, the step of providing feedback in the traffic state being performed with a second frequency, the second frequency being greater than the first frequency.

16. The machine-readable medium of claim 15, wherein the feedback comprises reverse link pilot and rate control.

17. The machine-readable medium of claim 13, wherein the instructions, when executed by said at least one processor, further cause the wireless access terminal to perform operations comprising:

transitioning from the dormant state to the active hold state in response to simultaneous presence of forward link traffic and absence of reverse link traffic.

18. The machine-readable medium of claim 13, wherein initiating transitions between a traffic state, a dormant state, and an active hold state, comprises:

initiating a transition from the traffic state to the active hold state in response to absence of reverse link traffic during a first predetermined time period,

initiating a transition from the active hold state to the traffic state in response to presence of reverse link traffic,

initiating a transition from the active hold state to the dormant state in response to absence of forward link traffic and reverse link traffic during at least a second predetermined period,

initiating a transition from the dormant state to the traffic state in response to presence of reverse link traffic, and

after transitioning into the active hold state, remaining in the active hold state during simultaneous presence of forward link traffic and absence of reverse link traffic.

19. The machine-readable medium of claim 13, wherein the predetermined duty cycle threshold is less than fifty percent.

20. The machine-readable medium of claim 13, wherein the codeword on the RRI channel comprises a spare codeword on the RRI channel, wherein the spare codeword is otherwise unused at the radio network.

21. A wireless access terminal for communicating with a base transceiver station of a radio network, the wireless access terminal comprising:

a means for sending reverse link transmissions to the base transceiver station; and

a controller means for executing the program code to cause the wireless access terminal to perform steps comprising;

initiating transitions between a traffic state, a dormant state, and an active hold state, wherein the transitions between the traffic state and the active hold state are initiated by sending a codeword on the reverse rate indicator (RRI) channel,

receiving an indication of whether the radio network has granted the transitions on an acknowledgement (ACK) channel, and

powering off at least one component of the transmitter so that a duty cycle of said at least one component is less than a predetermined duty cycle threshold in the active hold state.

22. The wireless access terminal of claim 21, further comprising:

a means for receiving forward link transmissions from the base transceiver station,

wherein initiating transitions between a traffic state, a dormant state, and an active hold state comprises;

initiating a transition from the traffic state to the active hold state in response to absence of reverse link traffic during a first predetermined time period,

initiating a transition from the active hold state to the traffic state in response to presence of reverse link traffic,

initiating a transition from the active hold state to the dormant state in response to absence of forward link traffic and reverse link traffic during at least a second predetermined period,

initiating a transition from the dormant state to the traffic state in response to presence of reverse link traffic, and

after transitioning into the active hold state, remaining in the active hold state during simultaneous presence of forward link traffic and absence of reverse link traffic.

23. The wireless access terminal of claim 21, wherein the predetermined duty cycle threshold is less than fifty percent.

24. The wireless access terminal of claim 21, wherein the controller means is further configured to execute the program code to cause the wireless access terminal to power on said at least one component of the transmitter for at least a majority of time in the traffic state.

25. The wireless access terminal of claim 24, wherein the controller means is further configured to execute the program code to cause the wireless access terminal to provide feedback to the base transceiver station with a first frequency in the active hold state, and to provide feedback to the base transceiver station with a second frequency in the traffic state, the second frequency being greater than the first frequency.

26. The wireless access terminal of claim 25, wherein the second frequency is twice the first frequency.

27. The wireless access terminal of claim 25, wherein the second frequency is four times the first frequency.

28. The wireless access terminal of claim 25, wherein the feedback comprises reverse link pilot and forward link rate control.

29. The wireless access terminal of claim 24, wherein the controller means is further configured to execute the program code to cause the wireless access terminal to provide feedback to the base transceiver station once in eight slots in the active hold state, and to provide feedback to the base transceiver station once in four slots in the traffic state.

30. The wireless access terminal of claim 24, wherein the controller means is further configured to execute the program code to cause the wireless access terminal to provide feedback to the base transceiver station once in sixteen slots in the active hold state, and to provide feedback to the base transceiver station once in four slots in the traffic state.

31. The wireless access terminal of claim 21, wherein the controller means is further configured to execute the program code to cause the wireless access terminal to transition from the dormant state to the active hold state in response to simultaneous presence of forward link traffic and absence of reverse link traffic.

32. The wireless access terminal of claim 21, wherein the codeword on the RRI channel comprises a spare codeword on the RRI channel, wherein the spare codeword is otherwise unused at the radio network.

33. A method of operating a wireless access terminal for communicating with a base transceiver station of a radio network, the method comprising:

initiating transitions between a traffic state, a dormant state, and an active hold state, wherein the transitions between the traffic state and the active hold state are initiated by sending a codeword on the reverse rate indicator (RRI) channel and receiving an indication of whether the radio network has granted the transitions on an acknowledgement (ACK) channel; and

in the active hold state, powering off at least one component of a transmitter of the wireless access terminal so that a duty cycle of said at least one component is less than a predetermined duty cycle threshold in the active hold state.

34. The method of claim 33, wherein the predetermined duty cycle threshold is twenty-five percent.

35. The method of claim 34, further comprising:

causing the wireless access terminal to power on said at least one component of the transmitter for at least a majority of time in the traffic state.

36. The method of claim 35, further comprising:

providing feedback from the wireless access terminal to the base transceiver station in the active hold state, the step of providing feedback in the active hold state being performed with a first frequency; and

providing the feedback from the wireless access terminal to the base transceiver station in the traffic state, the step of providing feedback in the traffic state being performed with a second frequency, the second frequency being greater than the first frequency.

37. The method of claim 36, wherein the second frequency is at least twice the first frequency.

38. The method of claim 36, wherein the second frequency is at least four times the first frequency.

39. The method of claim 36, wherein the second frequency is about 150 Hertz, and the first frequency is about 75 Hertz.

40. The method of claim 36, wherein the second frequency is about 150 Hertz, and the first frequency is about 37.5 Hertz.

41. The method of claim 36, wherein the feedback comprises reverse link pilot and rate control.

42. The method of claim 36, wherein the feedback comprises data rate control (DRC).

43. The method of claim 36, wherein the feedback comprises data source control (DSC).

44. The method of claim 35, further comprising:

providing feedback from the wireless access terminal to the base transceiver station once in eight slots in the active hold state; and

providing feedback from the wireless access terminal to the base transceiver station once in four slots in the traffic state.

45. The method of claim 35, further comprising:

providing feedback from the wireless access terminal to the base transceiver station once in sixteen slots in the active hold state; and

providing feedback from the wireless access terminal to the base transceiver station once in four slots in the traffic state.

46. The method of claim 33, further comprising:

causing the wireless access terminal to transition from the dormant state to the active hold state in response to simultaneous presence of forward link traffic and absence of reverse link traffic.

47. The method of claim 33, further comprising:

receiving from the base transceiver station an acknowledgement of the codeword on the RRI channel; and

transitioning the wireless access terminal to the active hold state in response to the acknowledgement.

48. The method of claim 33, wherein initiating transitions between a traffic state, a dormant state, and an active hold state comprises:

initiating a transition from the traffic state to the active hold state in response to absence of reverse link traffic during a first predetermined time period,

initiating a transition from the active hold state to the traffic state in response to presence of reverse link traffic,

initiating a transition from the active hold state to the dormant state in response to absence of forward link traffic and reverse link traffic during at least a second predetermined period,

initiating a transition from the dormant state to the traffic state in response to presence of reverse link traffic, and

after transitioning into the active hold state, remaining in the active hold state during simultaneous presence of forward link traffic and absence of reverse link traffic.

49. The method of claim 33, wherein the predetermined duty cycle threshold is less than fifty percent.

50. The method of claim 33, wherein the codeword on the RRI channel comprises a spare codeword on the RRI channel, wherein the spare codeword is otherwise unused at the radio network.