Method and apparatus for minimizing power consumption during idle mode in wireless communication system

• US 9,888,443 B2
• Filed: 05/07/2011
• Issued: 02/06/2018
• Est. Priority Date: 05/07/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Kang-Gyu
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): Ghafoerkhan, Faiyazkhan
• Application Number:
  US13/696,779
• Publication Number:
  US 20130070631A1
• Time in Patent Office: 2,467 Days
• Field of Search: None
• CPC Class Codes: H04W 52/0225 using monitoring of external events, e.g. the presence of a signal
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like
• CPC Class Codes: H04W 68/02 Arrangements for increasing efficiency of notification or paging channel
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for minimizing power consumption of a terminal during a power saving mode operation in a wireless communication system includes acquiring synchronization using a frequency used in a first paging listen interval or a frequency selected in a first paging listen interval; measuring a signal quality based on the acquired synchronization; and according to the measured signal quality, determining a length of a wake-up interval for a second paging listen interval. Thus, the terminal operating in the idle mode can minimize the power consumption of the terminal through the efficient control of the synchronization acquisition overhead interval and the frequency reselection algorithm carried out based on and the channel change.

Claims

1. A method for an operation of a terminal in a wireless communication system, the method comprising:

determining a quality of a first paging signal received in a first paging listen interval;

determining, based on the quality of the first paging signal, a length of a wake-up period where the terminal performs a synchronization with a base station, the wake-up period comprised in a paging unavailable interval; and

receiving, based on performing the synchronization with the base station during the wake-up period having the determined length, a second paging signal in a second paging listen interval from the base station.

2. The method of claim 1, wherein the determining the length of the wake-up period based on the quality of the first paging signal comprises:

comparing the quality of the first paging signal received in the first paging listen interval and a quality of a previous paging signal received in a previous paging listen interval; and

selecting one of a plurality of predefined wake-up periods based on the comparison result.

3. The method of claim 1, further comprising:

determining whether to change a state transition region based on the quality of the first paging signal,

wherein the determining whether to change the state transition region comprises;

when the quality of the first paging signal received in the first paging listen interval is greater than or equal to a first threshold, storing a value for the quality of the first paging signal received in the first paging listen interval without reselecting a frequency;

when the quality of the first paging signal received in the first paging listen interval is less than a second threshold, reselecting the frequency and storing the value for the quality of the first paging signal received in the first paging listen interval; and

when the quality of the first paging signal received in the first paging listen interval is greater than the second threshold and less than the first threshold, changing to a dynamic state transition region by comparing the quality of the first paging signal received in the first paging listen interval and a quality of a previous paging signal received in a previous paging listen interval.

4. The method of claim 3, wherein the first threshold is a maximum value of a quality of a paging signal with the state transition region, and the second threshold is a minimum value of the quality of the paging signal with the state transition.

5. The method of claim 4, wherein the second threshold is determined based on a maximum terminal travel speed and a terminal travel distance during a paging cycle, and the first threshold is determined as an offset of a second offset.

6. The method of claim 3, wherein the changing to the dynamic state transition region by comparing the quality of the first paging signal received in the first paging listen interval and the quality of the previous paging signal received in the previous paging listen interval,

changes S_n→

S<sub>n−

1</sub> when the quality of the first paging signal received in the first paging listen interval is greater than or equal to the quality of the previous paging signal received in the previous paging listen interval, and

changes S_n→

S_{n31 1} when the quality of the first paging signal received in the first paging listen interval is less than the quality of the previous paging signal received in the previous paging listen interval,

wherein the S_n, as a current state transition region, is an n-th transition state, S_n+1 is an n+1-th transition state region, and S<sub>n−

1</sub> is an n−

1-th transition state region.

7. The method of claim 6, wherein, when the S_n+1 is a maximum transition state region, the frequency is reselected.

8. The method of claim 1, determining the length of the wake-up period comprises:

if a value for indicating the determined quality is greater than a reference value, changing the length of the wake-up period from a first value to a second value greater than the first value; and

if the value is less than or equal to the reference value, changing the length of the wake-up period from the first value to a third value less than the first value.

9. A method for an operation of a terminal in a wireless communication system, the method comprising:

determining a quality of a first paging signal received in a first paging listen interval;

determining, based on the quality of the first paging signal, a length of a wake-up period where the terminal performs a synchronization with a base station, the wake-up period comprised in a paging unavailable interval;

selecting a frequency to use in a second paging listen interval based on the quality of the first paging signal; and

receiving, based on performing the synchronization with the base station during the wake-up period having the determined length, a second paging signal in the second paging listen interval from the base station.

10. The method of claim 9, wherein the determining the length of the wake-up period based on the quality of the first paging signal comprises:

comparing the quality of the first paging signal received in the first paging listen interval and a quality of a previous paging signal received in a previous paging listen interval; and

selecting one of a plurality of predefined wake-up periods based on the comparison result.

11. The method of claim 9, wherein the selecting the frequency to use in the second paging listen interval based on the quality of the first paging signal comprises:

when the quality of the first paging signal received in the first paging listen interval is greater than or equal to a first threshold, storing a value for the quality of the first paging signal received in the first paging listen interval without reselecting another frequency;

when the quality of the first paging signal received in the first paging listen interval is less than a second threshold, reselecting the another frequency and storing the value for the quality of the first paging signal received in the first paging listen interval; and

when the quality of the first paging signal received in the first paging listen interval is greater than the second threshold and less than the first threshold, changing to a dynamic state transition region by comparing the quality of the quality of the first paging signal received in the first paging listen interval and a quality of a previous paging signal received in a previous paging listen interval.

12. The method of claim 11, wherein the first threshold is a maximum value of a quality of a paging signal with a state transition region, and the second threshold is a minimum value of the quality of the paging signal with the state transition region.

13. The method of claim 12, wherein the second threshold is determined based on a maximum terminal travel speed and a terminal travel distance during a paging cycle, and the first threshold is determined as an offset of a second offset.

14. The method of claim 9, wherein the wake-up period is a time period required in a synchronization process.

15. A terminal in a wireless communication system, the terminal comprising:

a transceiver; and

at least one processor configured to;

determine a quality of a first paging signal received in a first paging listen interval;

determine, based on the quality of the first paging signal, a length of a wake-up period where the terminal performs a synchronization with a base station, the wake-up period comprised in a paging unavailable interval; and

receive, based on performing the synchronization with the base station during the wake-up period having the determined length, a second paging signal in a second paging listen interval from the base station.

16. The terminal of claim 15, wherein to determine the length of the wake-up period based on the quality of the first paging signal, the at least one processor is configured to:

compare the quality of the first paging signal received in the first paging listen interval and a quality of a previous paging signal received in a previous paging listen interval; and

select one of a plurality of predefined wake-up periods based on the comparison result.

17. The terminal of claim 15, wherein the at least one processor is further configured to determine whether to change a state transition region based on the quality of the first paging signal by:

when the quality of the first paging signal received in the first paging listen interval is greater than or equal to a first threshold, storing a value for the quality of the first paging signal received in the first paging listen interval without reselecting a frequency;

when the quality of the first paging signal received in the first paging listen interval is less than a second threshold, reselecting the frequency and storing the value for the quality of the first paging signal received in the first paging listen interval; and

when the quality of the first paging signal received in the first paging listen interval is greater than the second threshold and less than the first threshold, changing to a dynamic state transition region by comparing the quality of the first paging signal received in the first paging listen interval and a quality of a previous paging signal received in a previous paging listen interval.

18. The terminal of claim 17, wherein the first threshold is a maximum value of a quality of a paging signal with the state transition region, and the second threshold is a minimum value of the quality of the paging signal with the state transition.

19. The terminal of claim 18, wherein the second threshold is determined based on a maximum terminal travel speed and a terminal travel distance during a paging cycle, and the first threshold is determined as an offset of a second offset.

20. The terminal of claim 15, wherein the at least one processor is configured to control to:

if a value for indicating the determined quality is greater than a reference value, changing the length of the wake-up period from a first value to a second value less than the first value; and

if the value is less than or equal to the reference value, changing the length of the wake-up period from the first value to a third value greater than the first value.