Secrecy performance analysis of cooperative transmission and cooperative jamming for multi-tier heterogeneous cellular networks

Abstract

The particularity of security threats for multi-tier heterogeneous cellular networks (HCNs) is causedby the nonuniformity between the tiers and the complex and unplanned topology. To promote the study of secrecy transmission in HCNs, we utilize stochastic geometry tools and physical-layer security technologies to obtain theexpressions for the secrecy coverage probability and average secrecy rate under different scenarios such as nocooperation, only macrocell base stations (MBSs) involved in cooperation, all base stations (BSs) involved incooperation, and with/without channel measurements between the cooperative BSs and the mobile users. Furthermore,we simulate and analyze the influences on security performance caused by the fraction of transmit powerused for transmitting artificial noise, the fraction of cooperative power used for transmitting artificial noise, thesecrecy rate threshold, the number of transmission antennas for an MBS, and the eavesdropper density. Basedon the simulation results, we propose a security-performance-oriented strategy for cooperative transmission andjamming in HCN.