AVOIDANCE OF HFN DESYNCHRONIZATION IN UPLINK OVER WLAN IN LTE-WLAN AGGREGATION

摘要

A number of techniques for mitigating or eliminating hyper frame number (HFN) desynchronization, for uplink LWA, are described herein. In one embodiment, separate PDCP discard timers are maintained for packets sent over the WLAN and LTE links. The discard timers may be independently set for the WLAN and LTE links. In a second embodiment, status reports may be sent by the eNB, and to the UE, indicating acknowledgement (ACK) and/or negative acknowledgement (NACK) of uplink PDCP SDUs. The status reports may be transmitted periodically or after a certain number of packets are transmitted. In a third embodiment, retransmission of PDCP SDUs after being sent once over the WLAN link may be disabled.