Physical Layer Security of Multi-hop Aided Downlink MIMO heterogeneous Cellular Networks

This study investigates physical layer security in downlink multipleinput multiple-output(MIMO) multi-hop heterogeneous cellular networks(MHCNs),in which communication between mobile users and base stations(BSs) is established by a single or multiple hops,to address the problem of insufficient security performance of MIMO heterogeneous cellular networks.First,two-dimensional homogeneous Poisson point processes(HPPPs) are utilized to model the locations of K-tier BSs in MIMO MHCNs and receivers,including those of legitimate users and eavesdroppers.Second,based on the channel gain distribution and the statistics property of HPPP,the achievable ergodic rates of the main and eavesdropper channels in direct and ad hoc links are derived,respectively.Third,the secrecy coverage probability and the achievable ergodic secrecy throughput of downlink MIMO MHCNs are explored,and their expressions are derived.Lastly,the correctness of the theoretical derivation is verified through Monte Carlo simulations.

具有固定中继节点多跳小区结构

为了在低发射功率的前提下扩展蜂窝小区的覆盖范围,本文基于多跳通信模式,提出由中心基站负责固定中继节点接入,移动节点通过固定中继节点的多跳中继而连接基站的网络结构,即接人式多跳小区结构。此结构提供了在低成本条件下完成区域覆盖的方法。对该小区结构的覆盖特性进行了分析,结果显示具有3个或4个固定中继节点的多跳小区结构可以有效地实现基站覆盖范围的扩展。