METHOD AND APPARATUS FOR IMPROVING UNBALANCE OF SERVICE OF CELL EDGE IN WIRELESS LOCAL AREA NETWORK

• US 20100124204A1
• Filed: 11/20/2009
• Published: 05/20/2010
• Est. Priority Date: 11/20/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: WON, Sang-Yeon
• Granted Patent: US 8,576,802 B2
• Time in Patent Office: Days
• US Class Current: 370/332
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN). A method of an Access Point (AP) for improving unbalance at service of a cell edge in a WLAN includes monitoring for a continuous decrease of a signal strength of a station over a predefined duration, determining if the station is to handover, when the continuous decrease of the signal strength occurs, and decreasing a transmit power of the AP, when it is determined that the corresponding station is to handover.

Claims

1. A method of an Access Point (AP) for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the method comprising:

monitoring a signal strength of a station for a continuous decrease of the signal strength over a predefined duration;

determining if the station is to handover, when there is the continuous decrease of the signal strength; and

decreasing a transmit power of the AP, when it is determined that the station is to handover.

2. The method of claim 1, wherein determining if the station is to handover comprises:

calculating at least one of a packet retransmission time count and transmission rate of the station;

comparing the at least one of the calculated packet retransmission time count and the transmission rate with threshold values, respectively; and

determining if the station is to handover using a comparison result.

3. A method of an Access Point (AP) for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the method comprising:

monitoring a signal strength and transmission rate of a predetermined time slot of a station; and

decreasing a transmit power of the AP based on the signal strength and transmission rate of the station.

4. The method of claim 3, wherein decreasing the transmit power of the AP comprises one of:

decreasing the transmit power of the AP to a predetermined magnitude; and

decreasing the transmit power of the AP by a predetermined increment.

5. A method of an Access Point (AP) for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the method comprising:

monitoring for a continuous decrease of a signal strength of a station over a predefined duration;

determining if the station is to handover, when there is the continuous decrease of the signal strength of the station; and

sending a handover command to the station, when it is determined that the station is to handover.

6. A method of a station for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the method comprising:

monitoring a signal strength of an Access Point (AP); and

when the signal strength of the AP is less than a threshold value, performing a handover to a target AP.

7. The method of claim 6, wherein performing the handover comprises:

searching peripheral Access Points (APs) through a channel search procedure;

selecting, as the target AP, an AP having a highest signal strength from among the searched peripheral APs; and

performing authentication with the target AP.

8. A method of a station for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the method comprising:

receiving a handover command from an Access Point (AP) through control channel; and

upon receiving the handover command, performing a handover to a target AR

9. The method of claim 8, wherein performing the handover comprises:

searching peripheral Access Points (APs) through a channel search procedure;

selecting, as the target AP, an AP having a highest signal strength from among the searched peripheral APs; and

performing authentication with the target AP.

10. An Access Point (AP) for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the AP comprising:

a signal measurer for monitoring for a continuous decrease of a signal strength of a station over a predefined duration;

a handover controller for determining if the station is to handover, when the continuous decrease of the signal strength occurs; and

a power controller for decreasing a transmit power of the AP, when it is determined that the station is to handover.

11. The AP of claim 10, wherein the handover controller

calculates at least one of a packet retransmission time count and transmission rate of the station,

compares the at least one of the calculated packet retransmission time count and the transmission rate with threshold value, respectively, and

determines if the station is to handover using a comparison result.

12. An Access Point (AP) for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the AP comprising:

a controller for monitoring a signal strength and transmission rate of a predetermined time slot of a station; and

a power controller for decreasing a transmit power of the AP, based on the signal strength and transmission rate of the station.

13. The AP of claim 12, wherein the transmit power is decreased to a predetermined magnitude or by a predetermined amount.

14. An Access Point (AP) for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the AP comprising:

a signal measurer for monitoring for a continuous decrease of a signal strength of a station over a predefined duration; and

a handover controller for determining if the station is to handover, when the continuous decrease of the signal strength occurs, and for sending a handover command to the station, when it is determined that the station is to handover,.

15. A station for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the station comprising:

a signal measurer for monitoring a signal strength of an Access Point (AP); and

a handover manager for performing a handover to a target AP, when the signal strength of the AP is less than a threshold value.

16. The station of claim 15, wherein the handover manager

searches peripheral Access Points (APs) through a channel search procedure,

selects, as the target AP, an AP having a highest signal strength from among the searched peripheral APs, and

performs authentication with the target AP.

17. A station for improving unbalance of service at a cell edge in a Wireless Local Area Network (WLAN), the station comprising:

a Radio Frequency (RF) processor for receiving a handover command from an Access Point (AP); and

a handover manager for performing a handover to a target AP, based on the handover command.

18. The station of claim 17, wherein the handover manager

searches peripheral Access Points (APs) through a channel search procedure,

selects, as the target AP, an AP having a highest signal strength from among the searched peripheral APs, and

performs authentication with the target AP.