Cooperative beamforming based artificial noise in uplink wiretap channels

Jiasi Zhou, Wenjun Hou, Yijie Mao +1 more

The matter of information security within healthcare systems holds paramount importance. Therefore, the purpose of this letter is to enhance the secure communication for the uplink multiple-input multiple-output (MIMO) wiretap channel. Our objective is to augment the secrecy rate for legitimate users (LUs). We present a novel system that incorporates uplink rate splitting (RS) and a cooperative jamming scheme. The base station operates as a jammer, introducing artificial noise (AN) to prevent the leakage of information. Specifically, we optimize the transmit beamforming for the LUs and the AN covariance, with the aim of maximizing the minimum secrecy rate across all LUs. For this, we develop precise surrogate functions for the non-convex secrecy rates and propose an iterative alternating optimization (AO) algorithm. This algorithm updates auxiliary variables and transmit beamforming iteratively. Simulation results demonstrate the superiority of our proposed scheme over existing benchmarks, resulting in significant gains in secrecy rates.

Yizhen Zhang, Guobing Li, Guomei Zhang +1 more

Sungjun Ahn, Seungjae Jung, Wonju Lee +4 more

In this paper, we tackle the physical-layer security issue in MISO wiretap channel considering the pilot-assisted channel estimation at the receiver side. Unlike the conventional schemes, we introduce the cooperative jamming scheme that transmits artificial noise (AN) only on downlink pilot transmission phase. In order to disrupt the channel estimation at the eavesdropper (Eve) effectively, an optimal beamforming at the cooperative jammer (CJ) was obtained by means of difference-of-convex (DC) algorithm and rank relaxation. In addition, with focus on the energy budget limitation issue at the CJ, energy efficiency at the CJ is verified based on the circuit power consumption model. Numerical results provide a performance comparison with a conventional scheme, which transmits AN only in data transmission phase.

Yuan Ren, Hui Gao, Tiejun Lv

Minyan Pei, Jibo Wei, Kai‐Kit Wong +1 more

This letter investigates masked beamforming schemes for multiuser multiple-input multiple-output (MIMO) downlink systems in the presence of an eavesdropper. With noisy and outdated channel state information (CSI) at the base station (BS), we aim to maximize the transmit power of an artificial noise, which is broadcast to jam any potential eavesdropper, while meeting individual minimum mean square error (MMSE) constraints of the desired user links. To this end, we adopt a Bayesian approach and derive an average MSE uplink-downlink duality with imperfect CSI. Using the duality, a robust beamforming algorithm is proposed. Simulation results show the effectiveness of the proposed scheme.

He-hao, Niu, Bang-ning +7 more