Secure beamforming and power‐efficient artificial‐noise optimization for multibeam directional modulation

Abstract

In this article, an anti‐eavesdropping zero‐forcing plus power‐efficient artificial‐noise optimization method for multibeam directional modulation (DM) synthesis is proposed. It aims to prevent known and unknown eavesdroppers intercepting useful signals as far as possible and achieve a narrower bit error rate (BER) main beamwidth under the premise of limited artificial‐noise (AN) power consumption. Beam pattern nulls are generated in known eavesdroppers directions by utilizing the orthogonality of zero‐forcing beamforming. Low‐sidelobe beamforming is also introduced to DM for the first time to suppress unknown eavesdroppers outside main lobes. The distribution of AN power in all directions is optimized by minimizing the AN transmit power subject to a series of secrecy rate (SR) constraints. Simulation results show that the proposed method outperforms the state‐of‐the‐art DM synthesis methods with regard to power efficiency, SR and BER performance.

Position‐sensitivity security transmission with orbital angular momentum directional modulation based on frequency diverse array

“…The DM baseband signal adopts the artificial noise and the synthetic constellation can change dynamically in Reference 5, which eavesdroppers cannot monitor the law of the constellation distortion. In Reference 6, the orthogonality of zero‐forcing beamforming is used to generate beam pattern zeros in known eavesdroppers directions and achieve a narrower bit error rate (BER) main beamwidth. At present, most DM beams are generated based on the phased array, which can obtain range‐independent steering vector 7,8 …”