A Wire-Line Secure Communication System Based on CCFD Self-Interference Cancellation

Wenjian Lu,Sanjun Liu,Guohong Lai

doi:10.1051/wujns/2021266507

Abstract

This paper presents a design scheme of wire-line telephone system using self-interference (SI) cancellation technology in co-frequency co-time full-duplex (CCFD) system to realize absolute secure communication at the physical layer. This scheme can hide the target signal by skillfully releasing the high-power artificial noise to the whole link at the receiving node, and then make use of the receiver’s knowledge of the SI signal to achieve high dB SI cancellation with the help of analog domain SI cancellation technology in CCFD domain, so that the signal-to-noise ratio (SNR) received by the eavesdropper at any position of the link is far lower than that of the legitimate receiver, so as to realize the absolutely secure communication in the sense of Wyner principle. This paper not only puts forward the specific design scheme of absolutely secure communication telephone, but also analyzes the calculation of security capacity under different eavesdropping positions, different SI cancellation capability and different system parameters according to Shannon theory.

Highlights

Traditional wire-line secure communication systems mostly adopt encryption algorithms based on cipher key, such as DES algorithm[1] and AES algorithm[2]
This paper measures the security communication capability of the system by analyzing the security capacity of the wire-line communication system: if the maximum eavesdropping capacity obtained by Eve when eavesdropping the target signals from Alice and Bob at any eavesdropping position is less than the security capacity of the legal channel, the absolute physical layer security communication can be realized, otherwise there is the possibility of eavesdropping
This paper presents a wire-line secure communication system based on the co-frequency co-time SI cancellation technology, and studies the problem of absolutely secure communication in the process of wire-line communication

Summary

Introduction

Traditional wire-line secure communication systems mostly adopt encryption algorithms based on cipher key, such as DES algorithm[1] and AES algorithm[2]. In order to realize absolute physical layer security in the whole space, it must be ensured that there is a very high self-interference cancellation effect in all positions, which is difficult to achieve in practical applications. These studies do not give the specific SI cancellation scheme. Based on Wyner principle, this paper proposes a new design scheme of wired secure communication system, which gives up the traditional confidential methods, and uses the analog domain SI cancellation technology in CCFD[13] to enable both nodes of the full-duplex system to eliminate the artificial noise. Both the system security capacity calculation method and its relationship between SI cancellation capability will be studied in this paper

System Model

Analysis of System Security Capacity

Simulation Results and Analysis

Conclusion