Secure User Association in Ultra Dense Heterogeneous Cellular Networks with non-Uniformly Distributed Eavesdroppers

Abstract

Ultra-dense heterogeneous cellular networks (UD-HCNs) offer significant gains to network throughput and constitute a vital part of next generation wireless networks. However, due to the open access mode of small cells, they are vulnerable to wiretap attacks. In this paper we study the information-theoretic secure user association in a two-tier UDHCN where a random number of eavesdroppers coexist with legitimate users and attempt to wiretap the wireless channels. In particular, these eavesdroppers are assumed to proactively seek candidate base stations to maximize information leakage. We then devise a user association scheme that maximize network secrecy throughput. Simulation results show that compared with the traditional user association scheme, our proposed method improves network secrecy performance in terms of secrecy probability and capacity.