Energy efficient IEEE 802.11 WLAN discovery for heterogeneous 3GPP LTE network

Integration of IEEE 802.11 wireless local area networks with the 3GPP based cellular networks has attracted significant interest in recent releases of 3GPP. But the current scanning procedures used for the discovery of WLANs, implemented in most smartphones, is very inefficient due to unnecessary scan operations. In this paper, we have proposed modified scanning algorithms to reduce the amount of undesirable scans. In the proposed schemes, the UE schedules its scanning operations with assistance from the cellular network on the operator deployed WLAN network and offload policies. The simulation results in ns-3, with additional modules implemented for ANDSF and IEEE 802.11u for 3GPP-WLAN interworking, have shown significant improvement in energy consumption along with better association time for the users.