AIR LINK UP/DOWN PROTOCOL (ALUDP) Russian patent published in 2016 - IPC H04W76/02 

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to wireless communication. In an advanced broadband wireless system, an air link refers to a communication channel between a BS (base station) and a SS (subscriber station) using air as the medium. At a lower layer, the air link status may determine whether or not upper layer data may be transported over the air between the two ends of the air link. If data may be transported, the air link is considered "up", otherwise the air link is considered "down". The system may monitor, report and manage the air link status. A method of detecting coverage loss at a base station (BS) comprises: launching a coverage loss detection (CLD) timer for the SS; under the condition that the CLD timer for said SS expires: distributing an uplink (UL) grant to said SS to enable identification of the status of said SS; receiving an UL data packet from said SS through the distributed UL grant; resetting the CLD timer for said SS based on the received UL data packet from said SS; forwarding a unicast ranging acknowledgement (RNG-ACK) to said SS based on the received UL data packet from said SS, wherein said unicast RNG-ACK allows said SS to reset the timer for periodic ranging of said SS.

EFFECT: improved communication quality.

14 cl, 9 dwg