Method and apparatus for reducing power consumption of wireless LAN device

• US 20070058575A1
• Filed: 09/05/2006
• Published: 03/15/2007
• Est. Priority Date: 09/02/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Yang, Chil-youl, Kwon, Chang-yeul, Park, Joong-suk
• Granted Patent: US 8,116,245 B2
• Time in Patent Office: Days
• US Class Current: 370/318
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus for reducing the power consumption of a wireless LAN device that operates in a wireless network are disclosed. The method for reducing the power consumption includes receiving a high throughput (HT) frame; judging whether the received HT frame is decodable; and if the received HT frame is not decodable, switching the wireless LAN device into a standby mode, and maintaining the device in the standby mode for a duration of the HT frame.

Claims

1. A method of reducing power consumption of a wireless LAN device, comprising:

(a) receiving a high throughput (HT) frame;

(b) judging whether the received HT frame is decodable; and

(c) if the received HT frame is not decodable, switching the wireless LAN device into a standby mode, and maintaining the device in the standby mode for a duration of the HT frame.

2. The method of claim 1, further comprising (d) if it is judged in (b) that the HT frame is decodable, maintaining the device in a reception mode for the duration of the HT frame.

3. The method of claim 1, wherein a PHY header of the HT frame includes at least a legacy signal field (L-SIG field) and an HT signal field (HT-SIG field).

4. The method of claim 3, wherein the L-SIG field includes a RATE field for informing a legacy device of a transmission rate, and a LENGTH field informing the legacy device of a size of a MAC protocol data unit (MPDU) of the HT frame;

and the HT-SIG field includes an MCS field informing the HT device of a transmission characteristic, and an HT LENGTH field informing the HT device of the size of the MPDU of the HT frame.

5. The method of claim 4, wherein (b) judges whether the HT frame is decodable depending on whether the wireless LAN device supports the transmission characteristic.

6. The method of claim 4, wherein the duration is calculated by dividing a size recorded in the HT LENGTH field by the transmission rate indicated by an MCS index recorded in the MCS field.

7. The method of claim 1, wherein if the wireless LAN device is in a standby mode, the device consumes less than 5% of a maximum power.

8. The method of claim 1, further comprising (d) increasing the power to switch the standby mode into the reception mode for a specified time period before the expiration of the duration of the HT frame.

9. The method of claim 1, wherein (b) judges whether the HT frame is decodable according to a specified bit inserted into the HT frame.

10. A method of reducing power consumption of a wireless LAN device, comprising:

(a) receiving a high throughput (HT) frame;

(b) judging whether the received HT frame is decodable;

(c) if the received HT frame is not decodable, judging whether a spoofing occurs in the HT frame; and

(d) if it is judged in (c) that the spoofing occurs, switching the wireless LAN device into a standby mode, and maintaining the device in the standby mode for a legacy duration.

11. The method of claim 10, further comprising (e) if it is judged from (b) that the HT frame is decodable, maintaining the device in a reception mode for the legacy duration.

12. The method of claim 10, further comprising (e) if it is judged from (c) that no spoofing has occurred, switching the wireless LAN device into the standby mode, and maintaining the device in the standby mode for a duration of the HT frame.

13. The method of claim 10, wherein a PHY header of the HT frame includes a legacy signal field (L-SIG field) and an HT signal field (HT-SIG field).

14. The method of claim 13, wherein the L-SIG field includes a RATE field informing a legacy device of a transmission rate, and a LENGTH field informing the legacy device of a size of a MAC protocol data unit (MPDU) of the HT frame;

and the HT-SIG field includes an MCS field informing the HT device of a transmission characteristic, and an HT LENGTH field informing the HT device of the size of the MPDU of the HT frame.

15. The method of claim 14, wherein (b) judges whether the HT frame is decodable depending on whether the wireless LAN device supports the transmission characteristic.

16. The method of claim 14, wherein the duration of the HT frame is calculated by dividing a size value recorded in the HT LENGTH field by the transmission rate indicated by an MCS index recorded in the MCS field;

and the legacy duration is calculated by dividing a size value recorded in the LENGTH field by a transmission rate indicated by an index recorded in the RATE field.

17. The method of claim 16, wherein whether the spoofing has occurred is judged depending on whether the duration of the HT frame is identical to the legacy duration.

18. The method of claim 10, wherein (b) and (c) judges whether the HT frame is decodable and whether the spoofing has occurred according to a specified bit inserted into the HT frame, respectively.

19. A wireless LAN device comprising:

an RF unit which receives a high throughput (HT) frame;

a decoding judgment unit which judges whether the received HT frame is decodable;

a mode switching unit which switches the wireless LAN device into a standby mode if the received HT frame is not decodable, and maintains the device in the standby mode for a duration of the HT frame; and

a power source which supplies a corresponding power depending on a mode of the mode switching unit.

20. A wireless LAN device comprising:

an RF unit which receives a high throughput (HT) frame;

a decoding judgment unit which judges whether the received HT frame is decodable;

a mode switching unit which judges whether a spoofing has occurred in the HT frame if the received HT frame is not decodable, and if it is judged that spoofing has occurred, switches the wireless LAN device into a standby mode and maintains the device in the standby mode for a legacy duration; and

a power source which supplies a corresponding power depending on a mode of the mode switching unit.