Open AccessJoint optimization of beamforming and power allocation for DAJ‐based untrusted relay networks
Author(s) -
Yao Rugui,
Lu Yanan,
Mekkawy Tamer,
Xu Fei,
Zuo Xiaoya
Publication year - 2018
Publication title -
etri journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 46
eISSN - 2233-7326
pISSN - 1225-6463
DOI - 10.4218/etrij.2018-0145
Subject(s) - jamming , beamforming , computer science , computer network , relay , secure transmission , power (physics) , electronic engineering , telecommunications , engineering , encryption , physics , quantum mechanics , thermodynamics
Destination‐assisted jamming (DAJ) is usually used to protect confidential information against untrusted relays and eavesdroppers in wireless networks. In this paper, a DAJ‐based untrusted relay network with multiple antennas installed is presented. To increase the secrecy, a joint optimization of beamforming and power allocation at the source and destination is studied. A matched‐filter precoder is introduced to maximize the cooperative jamming signal by directing cooperative jamming signals toward untrusted relays. Then, based on generalized singular‐value decomposition (GSVD), a novel transmitted precoder for confidential signals is devised to align the signal into the subspace corresponding to the confidential transmission channel. To decouple the precoder design and optimal power allocation, an iterative algorithm is proposed to jointly optimize the above parameters. Numerical results validate the effectiveness of the proposed scheme. Compared with other schemes, the proposed scheme shows significant improvement in terms of security performance.