Abstract
This paper studies the use of multi-Antenna harvest-And-jam (HJ) helpers in a multi-Antenna amplify-And-forward (AF) relay wiretap channel assuming that the direct link between the source and destination is broken. Our objective is to maximize the secrecy rate at the destination subject to the transmit power constraints of the AF relay and the HJ helpers. In the case of perfect channel state information (CSI), the joint optimization of the artificial noise (AN) covariance matrix for cooperative jamming and the AF beamforming matrix is studied using semidefinite relaxation (SDR) which is tight, while suboptimal solutions are also devised with lower complexity. For the imperfect CSI case, we provide the equivalent reformulation of the worst-case robust optimization to maximize the minimum achievable secrecy rate. Inspired by the optimal solution to the case of perfect CSI, a suboptimal robust scheme is proposed striking a good tradeoff between complexity and performance. Finally, numerical results for various settings are provided to evaluate the proposed schemes.
| Original language | English |
|---|---|
| Article number | 7254226 |
| Pages (from-to) | 6616-6631 |
| Number of pages | 16 |
| Journal | IEEE Transactions on Signal Processing |
| Volume | 63 |
| Issue number | 24 |
| DOIs | |
| Publication status | Published - 15 Dec 2015 |
| Externally published | Yes |
Keywords
- Amplify-And-forward relay
- artificial noise
- cooperative jamming
- harvest-And-jam
- physical-layer security
- robust optimization
- semidefinite relaxation
- wireless energy transfer
ASJC Scopus subject areas
- Signal Processing
- Electrical and Electronic Engineering