The Gaussian Wiretap Channel with a Helping Interferer

• DOI: 10.48550/arxiv.0805.0108
• Publication Date: 2008-01-01
• Authors: Xiaojun Tang; Ruoheng Liu; Predrag Spasojević; H. Vincent Poor
• Keywords: FOS: Computer and information sciences; Computer Science - Cryptography and Security; Computer Science - Information Theory; Information Theory (cs.IT); 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology; Cryptography and Security (cs.CR)

Due to the broadcast nature of wireless medium, communication is susceptible adversarial eavesdropping. This paper describes how eavesdropping can potentially be defeated by exploiting superposition medium. A Gaussian wire-tap channel with a helping interferer (WTC-HI) considered in which transmitter sends confidential messages its intended receiver presence passive eavesdropper and help an interferer. The interferer, does not know message assists transmission sending signal that independent transmitted message. An achievable secrecy rate Sato-type upper bound on capacity are given for WTC-HI. Through numerical analysis, it found close when interference weak symmetric channels, under more general conditions asymmetric channels.