Millimeter-wave (mmWave) communication systems are realized to play a key role in next-generation communication systems to achieve high data rate requirements, allowing manifold connected devices and efficient bandwidth utilization. Although mmWave communication has severe degradation problems, security is considered as one of the most important issues. The objective of this study is to analyze and compare the effectiveness of secure communication among the transmitter, legitimate receiver and illegal user using different hybrid precoding and combining algorithms (phase extraction alternate minimizing (PE-AltMin), manifold optimization (MO-AltMin), spatially sparse precoding (SSP) and most recent reported algorithm in the literature). In this study, standard PE-AltMin and MO-AltMin algorithms are also modified in digital baseband domain to achieve better results. The security is achieved in two steps. First, cooperative analog precoder and combiner design algorithms are utilized to get RF precoder and combiner, and then, digital precoder and combiner are attained based on effective baseband digital channel. The simulation studies validate the impact of modified PE-AltMin algorithm that realizes better secrecy rate results than the other hybrid algorithms and ensures the most protected transmission. In simpler words, the utilization of proposed PE-AltMin hybrid algorithm offers the least information leakage towards Eavesdropper than others.

毫米波（mmWave）通信系统被实现为在下一代通信系统中发挥关键作用，以实现高数据速率要求，从而实现多种连接设备和高效带宽利用。尽管mmWave通信存在严重的降级问题，但是安全性被认为是最重要的问题之一。这项研究的目的是分析和比较使用不同的混合预编码和组合算法（相位提取交替最小化（PE-AltMin），流形优化（MO-AltMin），空间稀疏预编码（SSP）和文献中最新报道的算法）。在这个研究中，标准的PE-AltMin和MO-AltMin算法也在数字基带域中进行了修改，以实现更好的结果。安全性分两步实现。首先利用协同模拟预编码器和组合器设计算法得到RF预编码器和组合器，然后基于有效的基带数字信道获得数字预编码器和组合器。仿真研究验证了改进的PE-AltMin算法的影响，该算法实现了比其他混合算法更好的保密率结果，并确保了最受保护的传输。用简单的话来说，所提出的PE-AltMin混合算法的利用提供了最少的信息泄露给窃听者。利用协同模拟预编码器和组合器的设计算法得到RF预编码器和组合器，然后基于有效的基带数字信道获得数字预编码器和组合器。仿真研究验证了改进的PE-AltMin算法的影响，该算法实现了比其他混合算法更好的保密率结果，并确保了最受保护的传输。用简单的话来说，所提出的PE-AltMin混合算法的利用提供了最少的信息泄露给窃听者。利用协同模拟预编码器和组合器的设计算法得到RF预编码器和组合器，然后基于有效的基带数字信道获得数字预编码器和组合器。仿真研究验证了改进的PE-AltMin算法的影响，该算法实现了比其他混合算法更好的保密率结果，并确保了最受保护的传输。用简单的话来说，所提出的PE-AltMin混合算法的利用提供了最少的信息泄露给窃听者。