Method and apparatus for controlling power consumption of stations on a CSMA/CA-based wireless LAN

• US 7,953,030 B2
• Filed: 07/27/2004
• Issued: 05/31/2011
• Est. Priority Date: 07/28/2003
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Hwang, Hyo-sun, Jang, Kyung-hun, Cho, Jin-youn, Seo, Chang-woo, Chang, Jin-bong, Woo, Sang-hyun
• Primary Examiner(s): Moe; Aung S
• Assistant Examiner(s): Louis; Vinncelas
• Application Number:
  US10/899,130
• Publication Number:
  US 20050025106A1
• Time in Patent Office: 2,499 Days
• Field of Search: 370/318, 370/311, 370/338, 370/278, 370/392, 455/13.4, 455/522, 455571-574, 455/127.1, 455/127.5, 4553431-3436, 455/260, 455/255, 455/258, 455/259, 455/262, 455/265, 331/16, 331/17, 331/103, 342/357.1, 701/213, 701/214, 375/316, 375/215, 375/294, 375/327, 375/373, 375/376, 713/320, 713/324, 340/870.02, 340/7.32
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus controls power consumption of stations having a hierarchical structure when the stations transmit and receive a wireless signal to and from one another on a CSMA/CA wireless LAN. The controlling involves extracting information on frame transmission speed and transmission period information on first and second layers of the hierarchical structure from the wireless signal; determining a power-controlled period for each of the first and second layers based on the extracted information; and reducing the power consumption of the first and second layers by switching a current mode of the first and second layers to a predetermined mode for the power-controlled period if a reception address included in the extracted information is not identical to an address of the station.

Claims

1. A method of controlling power consumption of a station when it receives a wireless local area network signal using a hierarchical structure having a first layer and a second layer, the method comprising:

extracting information on frame transmission speed and transmission period information on the first and second layers from the wireless signal;

determining a power-controlled period for each of the first and second layers based on the extracted information;

reducing the power consumption of the first and second layers by switching an original mode of the first and second layers to a predetermined mode during the power-controlled period if a reception address included in the extracted information is not identical to an address of the station; and

maintaining the power consumption of the first and second layers at the original mode only when the reception address included in the extracted information is identical to the address of the station,

wherein the first layer is an RF layer and the second layer is a baseband layer, and

wherein in the predetermined mode, all the elements of the RF layer except for a PLL (Phase Locked Loop) and a first register are powered down and all the elements of the baseband layer except for a second register are powered down.

2. The method as claimed in claim 1, further comprising:

counting the power-controlled period for each of the first and second layers;

returning the first layer to its original mode if the power-controlled period for the first layer is over; and

returning the second layer to its original mode if the power-controlled period for the second layer is over.

3. The method as claimed in claim 1, further comprising, after the power-controlled period is over:

returning the first layer to its original mode; and

returning the second layer to its original mode after the first layer is returned to its original mode.

4. The method as claimed in claim 1, wherein if the reception address included in the excluded information is identical to the address of the station, the station receives the wireless signal via the first and second layers.

5. The method as claimed in claim 1, further comprising determining, after determining the power-controlled period, whether the reception address included in the extracted information is identical to the address of the station.

6. The method as claimed in claim 1, wherein, in the predetermined mode, selected elements of the first and second layers, which require less time to be stabilized after being powered than other elements of the first and second layers.

7. An apparatus for controlling power consumption of a station when it receives a wireless local area network signal using a hierarchical structure, the apparatus comprising:

a first layer of the hierarchical structure, the first layer for converting the wireless signal into a baseband signal;

a second layer of the hierarchical structure, the second layer for restoring an original signal from the baseband signal; and

a received power controller, which determines a power-controlled period for each of the first and second layers and reduces the power consumed by the first and second layers during the power-controlled period by switching an original mode of the first and second layers to a predetermined mode when a reception address included in the restored original signal is not identical to an address of the station, and maintaining the power consumption of the first and second layers at the original mode only when the reception address is identical to the address of the station,

wherein the first layer is an RF layer and the second layer is a baseband layer, and

wherein in the predetermined mode, all the elements of the RF layer except for a PLL (Phase Locked Loot)) and a first register are powered down and all the elements of the baseband layer except for a second register are powered down.

8. The apparatus as claimed in claim 7, wherein the first layer comprises:

a signal processor, which converts the wireless signal into the baseband signal;

a reference frequency provider, which provides the signal processor with a reference frequency; and

a first register, which stores data necessary for the operation of the signal processor,

wherein the received power controller supplies power only to the reference frequency provider and the first register in the predetermined mode.

9. The apparatus as claimed in claim 8, wherein the second layer comprises:

an analog-to-digital converter, which converts the baseband signal into a digital signal;

a baseband signal processor, which restores the original signal from the digital signal; and

a second register, which stores data necessary for the operation of the analog-to-digital converter or the baseband signal processor,

wherein the received power controller supplies power only to the second register in the predetermined mode.

10. The apparatus as claimed in claim 7, wherein the second layer comprises:

an analog-to-digital converter, which converts the baseband signal into a digital signal;

a baseband signal processor, which restores the original signal from the digital signal; and

a second register, which stores data necessary for the operation of the analog-to-digital converter or the baseband signal processor,

wherein the received power controller supplies power only to the second register in the predetermined mode.

11. The apparatus as claimed in claim 7, wherein the received power controller determines the power-controlled period for each of the first and second layers based on the restored original signal.

12. The apparatus as claimed in claim 11, wherein the first layer is restored to its original mode before the second layer is restored to its original mode.

13. The apparatus as claimed in claim 7, wherein the received power controller determines, after the power-controlled period is determined, whether the reception address included in the restored original signal is identical to the address of the station.

14. The apparatus as claimed in claim 7, wherein, in the predetermined mode, selected elements of the first and second layers, which require less time to be stabilized after being powered than other elements of the first and second layers.