Low-Complexity Physical Layer Security Technique Using Uniform Linear Arrays

Exploiting the immanent randomness of the wireless networks, physical layer security (PLS) is an promising technique that can overcome the limitations of conventional security schemes based on cryptography. Most of the existing PLS algorithms employ multiple antennas, which are used for digital beamforming. However, while it is challenging to adjust both amplitude and phase, because of significant energy consumption if the number of antennas is large. Thus, in this paper, we consider an analog beamforming-based PLS algorithm, which consumes considerably lower energy. In addition, motivated by the simple line-of-sight (LoS) channel assumption in prior work for analog beamforming-based PLS, we investigate the impact of the fading and scattering effects, assuming Rician fading channels, which has both LoS and non-LoS components. Through simulation, we show that secrecy rate decreases as the Rician K factor increases.