APPARATUS AND METHOD OF POWER SAVING FOR STATIONS IN WIRELESS COMMUNICATION SYSTEM

• US 20110149855A1
• Filed: 12/16/2010
• Published: 06/23/2011
• Est. Priority Date: 12/17/2009
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: CHO, Seungkwon, Park, Jaewoo, Lee, Sok-Kyu
• Granted Patent: US 8,611,266 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04W 52/0251 using monitoring of local events, e.g. events related to user activity
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A power control apparatus of a wireless communication terminal providing a voice over internet protocol (VoIP) service in a wireless communication system includes a user interface unit configured to include a voice CODEC using in the VoIP service, a controller configured to be connected to the user interface unit, include predetermined application programs including a VoIP application program, and control signaling for setting up a VoIP call and canceling a VoIP call, and a medium access control (MAC) processor configured to perform a medium access control function and include a timer unit for beginning a unscheduled-service period (U-SP) by receiving a VoIP call setup signal and a VoIP call cancel signal from the controller.

Claims

1. A power control apparatus of a wireless communication terminal providing a voice over internet protocol (VoIP) service in a wireless communication system, comprising:

a user interface unit configured to include a voice CODEC using in the VoIP service;

a controller configured to be connected to the user interface unit, include predetermined application programs including a VoIP application program, and control signaling for setting up a VoIP call and canceling a VoIP call; and

a medium access control (MAC) processor configured to perform a medium access control function and include a timer unit for beginning a unscheduled-service period (U-SP) by receiving a VoIP call setup signal and a VoIP call cancel signal from the controller.

2. The power control apparatus of claim 1, further comprising:

a physical layer unit configured to be connected to the MAC processor, receive data from the MAC processor, encode and modulate the received data to a radio frequency (RF) signal to be suitable to a predetermined wireless channel environment, transfer the RF signal to an access point, receive a RF signal from the access point, demodulate and decode the RF signal to data, and transfer the data to the MAC processor; and

a power supply configured to supply power to the wireless communication terminal.

3. The power control apparatus of claim 1, wherein a trigger frame is regularly transmitted at a predetermined interval to the uplink after setting up a VoIP call.

4. A method for controlling power of a wireless communication terminal supporting a voice over internet protocol (VoIP) service using an unscheduled automatic power saving delivery (U-APSD) method after setting up four access categories as a delivery-enabled state in a wireless communication system, comprising:

initializing a timer when a VoIP call is setup for starting the VoIP service;

determining whether the VoIP call is terminated or not when a frame of an access category setup as a trigger-enabled state is not transmitted to an access point;

transmitting a trigger frame to the access point when it is determined that the VoIP call is not terminated and when a current timer value exceeds a predetermined timer maximum value; and

receiving buffered data from the access point that receives the trigger frame.

5. The method of claim 4, wherein the buffered data is received from the access point when a frame of the access category setup as the trigger-enabled state is transmitted to the access point.

6. The method of claim 4, wherein the timer is interrupted when the VoIP call is terminated.

7. The method of claim 4, wherein it is determined whether the frame of the access category setup as the trigger enabled state is transmitted or not when the maximum timer value does not exceed the current timer value.

8. The method of claim 4, further comprising determining whether an End of Service Period (EOSP) field is set up or not when the buffered data is received from the access point and initializing the timer when the ESOP field is set up.

9. The method of claim 8, wherein data is continuously received from the access point when the EOSP field is not set up.

10. The method of claim 8, wherein the predetermined maximum timer value is decided based on a voice CODEC packet generation cycle of the wireless communication terminal.

11. The method of claim 8, when the VoIP service is not supported, comprising:

receiving a beacon frame from the access point, and determining whether the access point includes buffered data or not by analyzing a traffic indication message (TIM) field in the received beacon frame;

transmitting a trigger frame to the access point when it is determined that the access point includes the buffered data; and

receiving the buffered data from the access point that receives the trigger frame.

12. The method of claim 11, further comprising:

inspecting the EOSP field when the buffered data is received from the access point, terminating receiving the buffered data when the EOSP field is setup, and waiting for receiving a next beacon frame.

13. The method of claim 11, wherein the buffered data is continuously received when the EOSP field is not set up.

14. The method of claim 11, wherein a next beacon frame is waited when the access point does not include the buffered data.