Public Safety Priority-Based User Association for Load Balancing and Interference Reduction in PS-LTE Systems

This paper addresses the issues of user association in multi-tier heterogeneous networks (HetNets) to reduce co-channel interference and provide load balancing for proactively of loading users onto mobile personal cells (mPC). Previously, much of the literature discussed the user' association problem for HetNets with conventional fixed small cells. The problem discussed in the existing literature is easy to analyze owing to fix nature of the small cells. In this paper, we focus on the mPC instead of fixed small cells, which complicates the user association problem due to its nature of mobility. In this paper, we propose the public safety ( PS) users priority-based mPC user association (PS-UA) scheme for load balancing and interference reduction in highly fluctuating PS long-term evolution systems. The proposed scheme improves the user-association problem by minimizing call blocking probability (CBP) according to the network load conditions and PS user priority. Moreover, it further improves user signal-to-interference-and-noise ratio by implementing enhanced intercell interference coordination scheme to further reduce the interference to the off loaded users. System-level simulations confirrmed the validity of the proposed PS-UA scheme, because it convincingly reduces the CBP for PS users as compared with the conventional static user association scheme.