Performance Evaluation of an Advanced Energy-aware Client-based Handover Solution in Heterogeneous LTE and WiFi Networks

The pervasive use of smartphones in daily life and the advanced expansion of cellular networks (LTE) has strongly increased the amount of mobile data traffic and has established the trend of always on connectivity. To cope with the huge amount of data, WiFi offload has become an indispensable solution. Keeping in mind the resource constraints of smartphones, energy-aware applications are of high importance. Vertical handover decision algorithms (VHDA) are indispensable for the balance and coordination of heterogeneous networks capacity and the handling of the increased amount of data traffic. In this paper we present an energy metric for vertical handover decision algorithms (VHDA) derived from measurements. Furthermore, we propose a client-based lightweight handover solution with an integrated energy-aware vertical handover decision algorithm based on Fuzzy logic. We analyze the handover delay and the energy consumption in a laboratory as well as in a real environment and compare our results with a RSS based solution. We show that our client-based energy-aware handover solution (EC) fulfills the requirement of small handover delays (<= 200ms) and outperforms RSS based solutions in terms of energy efficiency (E/Bit).