PERIODIC RANGING IN A WIRELESS ACCESS SYSTEM FOR MOBILE STATION IN SLEEP MODE

• US 20090233654A1
• Filed: 05/21/2009
• Published: 09/17/2009
• Est. Priority Date: 08/09/2004
• Status: Active Grant

• Current Assignee: Beum-Joon Kim, Chang-Jae Lee, Ki-Seon Ryu
• Original Assignee: Beum-Joon Kim, Chang-Jae Lee, Ki-Seon Ryu
• Inventors: LEE, Chang-Jae, Ryu, Ki-Seon, Kim, Beum-Joon
• Granted Patent: US 7,672,696 B2
• Time in Patent Office: Days
• US Class Current: 455/574
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method of performing a ranging process between a base station and a mobile station in sleep mode in a wireless access system, wherein the base station provides the mobile station with an initial notification of a periodic ranging time that occurs during a sleep time interval and during which the mobile station is to perform the ranging process, the initial notification included in a first message, the first message indicating whether the mobile station should terminate sleep mode to receive downlink data, and wherein the base station provides the mobile station with subsequent notifications of periodic ranging times that occur during the sleep time interval, the subsequent notifications indicated in a second message, the second message transmitted to the mobile station as part of the ranging process such that the mobile station performs a plurality of ranging processes within the sleep time interval.

Claims

1-25. -25. (canceled)

26. A method of determining when to terminate a sleep mode between a base station and a mobile station in a wireless access system, comprising:

receiving a traffic indication message during a listening interval from the base station;

receiving a ranging response message from the base station in response to a ranging request message transmitted to the base station through uplink resources allocated by the base station, wherein the ranging response message comprises a next periodic ranging time;

checking whether or not one of the traffic indication message and the ranging response message indicates that downlink traffic exists;

maintaining a sleep mode if the traffic indication message indicates that downlink traffic does not exist;

when the next periodic ranging time has been reached, transmitting another ranging request message to the base station through the uplink resources allocated by the base station if the ranging response message indicates downlink traffic does not exist; and

terminating the sleep mode and receiving data if the traffic indication message or the ranging response message indicates that downlink traffic exists.

27. The method of claim 26, wherein the ranging response message indicates that downlink traffic exists by having a value of the next periodic ranging time set to zero.

28. The method of claim 26, the next periodic ranging time in the ranging response message has a type length value (TLV) form.

29. A mobile subscriber station of a wireless communication system, the mobile subscriber station configured to perform the following functions while in a sleep mode:

receive a traffic indication message during a listening interval from a base station;

receive a ranging response message from the base station in response to a ranging request message transmitted to the base station through uplink resources allocated by the base station, wherein the ranging response message comprises a next periodic ranging time;

check whether or not one of the traffic indication message and the ranging response message indicates that downlink traffic exists;

maintain a sleep mode if the traffic indication message indicates that downlink traffic does not exist;

when the next periodic ranging time has been reached, transmit another ranging request message to the base station through the uplink resources allocated by the base station if the ranging response message indicates downlink traffic does not exist; and

terminate the sleep mode and receiving data if the traffic indication message or the ranging response message indicates that downlink traffic exists.

30. The mobile subscriber station of claim 29, wherein the ranging response message indicates that downlink traffic exists by having a value of the next periodic ranging time set to zero.

31. The mobile subscriber station of claim 29, the next periodic ranging time in the ranging response message has a type length value (TLV) form.