A simple speed estimation algorithm for mobility-aware SON RRM strategies in LTE

Mobility management in so-called heterogeneous networks (HetNets) becomes a complicated issue because of the increased complexity of inter-layer Radio Resource Management (RRM) techniques. Frequent inter-layer reselections and handovers should be minimized when dealing with high-speed users by taking into account both user speeds and relative cell sizes. In this paper we propose a simple User Equipment (UE) speed estimation algorithm for application in mobility-aware cell reselection and handover strategies in Long Term Evolution (LTE) wireless networks where Self-Organising Networks (SON) are intended to play a key role. The suitability of mobility-aware RRM strategies based on the exchange of speed and cell size information between terminals and base stations is analysed. A simple structure for speed detection is proposed that relies on the analysis of the downlink Doppler spread spectrum. Simulations show that the proposed algorithm is accurate enough for performing advanced RRM techniques based on user speed.