Patent ID: 9468034
Filing Date: 2016-10-11
CPC Classification: H04W

Claim Text:
1. A method for performing a coverage loss detection procedure at a base station in a wireless communication system, the method comprising: transmitting an unsolicited advanced air interface ranging response (unsolicited AAI-RNG-RSP) message to a mobile station, wherein the unsolicited AAI-RNG-RSP message includes an indicator bit set to ‘1’ to request the mobile station to perform a ranging; starting a first timer when the unsolicited AAI-RNG-RSP message is transmitted; receiving an advanced air interface ranging confirmation (AAI-RNG-CFM) message including a station identifier (STID) of the mobile station after a successful periodic ranging, the AAI-RNG-CFM message indicating the successful periodic ranging initiated by the unsolicited AAI-RNG-RSP message; and starting a second timer if the AAI-RNG-CFM message is not received from the mobile station upon expiration of the first timer, wherein the second timer is related to a retention period of context of the mobile station.