Artificial Noise Aided Secure Transmission in Active RIS-Assisted CF System Without Eavesdroppers' CSI

Zihang Huang, Limeng Dong, Xiao Tang, Yiran Huo, Jiale Shi

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

Reconfigurable Intelligent Surface (RIS) has emerged as a key technology capable of economically and efficiently reconfiguring wireless communication environments, and has been widely utilized to assist secure transmission in cell-free (CF) system in recent years. However, due to the presence of multiplicative fading effects, traditional passive RIS typically performs poorly when deployed far from the access point (AP) and users. Additionally, eavesdroppers (Eves) are malicious users hidden within the system, making it difficult for the system to acquire their channel state information (CSI). To address above issues, this paper investigates secure transmission of CF system aided by multiple active RISs. By considering no Eves' CSI, we propose an artificial noise (AN) aided transmssion strategy to enhance the secure transmission of system. In this strategy, the system total power is divided into two parts at the APs, one for the signal transmission and one for the AN signaling. To allocate the first part of power, we propose an efficient alternating optimization (AO) algorithm to optimize the active and passive beamformers at APs and RISs by ensuring that the users' quality of service (QoS) for communication is satisfied. To allocate the second part of residual power, we propose equal and unequal power allocation strategies for transmitting artificial noise (AN) so as to degrade Eves' signal reception performance. The simulation results show that compared with the benchmark schemes, our proposed method with the aide of active RISs in CF system can more effectively suppresse the performance of Eves, which in turn significantly enhances the secrecy rate for users in the system.

Original languageEnglish
Title of host publication2025 IEEE Wireless Communications and Networking Conference, WCNC 2025
PublisherInstitute of Electrical and Electronics Engineers Inc.
ISBN (Electronic)9798350368369
DOIs
StatePublished - 2025
Event2025 IEEE Wireless Communications and Networking Conference, WCNC 2025 - Milan, Italy
Duration: 24 Mar 202527 Mar 2025

Publication series

NameIEEE Wireless Communications and Networking Conference, WCNC
ISSN (Print)1525-3511

Conference

Conference2025 IEEE Wireless Communications and Networking Conference, WCNC 2025
Country/TerritoryItaly
CityMilan
Period24/03/2527/03/25

Keywords

  • Active reconfigurable intelligent surface
  • artificial noise
  • cell-free
  • eavesdropper

Fingerprint

Dive into the research topics of 'Artificial Noise Aided Secure Transmission in Active RIS-Assisted CF System Without Eavesdroppers' CSI'. Together they form a unique fingerprint.

Cite this