This letter studies the secrecy capacity of the millimeter Wave (mmWave) Generalized Spatial Modulation (GSM) system with hybrid precoding. First of all, the capacity of the mmWave GSM system with Gram-Schmidt precoding is analyzed. Secondly, the influence of the shared scatterers on the secrecy capacity is explored under the wire-tap channel. Finally, artificial noise, which has no influence on legitimate user but can interfere with the eavesdropping user, is adopted to prevent eavesdropping. Simulation results show that in the most SNR region, the secrecy capacity of the proposed scheme is higher than that of the system directly adopting orthogonal matching pursuit, phase extraction alternating minimization, and semidefinite relaxation alternating minimization precoding algorithms.

中文翻译：

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毫米波 MIMO 系统中的混合预编码辅助安全广义空间调制


这封信研究了具有混合预编码的毫米波 (mmWave) 通用空间调制 (GSM) 系统的保密能力。首先，分析了采用 Gram-Schmidt 预编码的毫米波 GSM 系统的容量。其次，探讨了窃听信道下共享散射体对保密能力的影响。最后，采用对合法用户没有影响但会对窃听用户产生干扰的人工噪声来防止窃听。仿真结果表明，在最大信噪比区域，该方案的保密能力高于直接采用正交匹配追踪、相位提取交替最小化和半定松弛交替最小化预编码算法的系统。