论文标题
通过IRS提高了定向调制网络的保密率最大化
Enhanced Secrecy Rate Maximization for Directional Modulation Networks via IRS
论文作者
论文摘要
智能反射表面（IRS）具有低成本和能源效率，对于未来的无线通信（如第六代）将是一项有前途的技术。为了解决常规定向调制（DM）的问题，即爱丽丝仅将单个机密位平流（CBS）传输到Bob中，并在视线渠道中具有多个天线，建议IRS为DM创建友好的多径，以使两个CBS可以从爱丽丝传输到鲍勃。这将显着提高DM的保密率（SR）。为了最大化SR（MAX-SR），通过IRS相移矩阵（PSM）的单位模式约束来提出一个一般的非凸优化问题，并提出了一般交替的迭代（GAI）算法，以共同获得递送光束成型的载体（TBVS）和PSM，并通过另一种固定一个并固定在另一个和固定的。为了降低其高复杂性，通过将空空间（NS）的约束（NS）的约束（称为NS投影（NSP））放置，提出了Max-SR的低复杂性迭代算法。在这里，每个CBS在其他CBS和AN通道的NSS中分别传输。仿真结果表明，所提出的GAI和NSP的SRS大约可以在高信噪比区域中用于大量IRS的单个CBS基于IRS的DM的SRS。
Intelligent reflecting surface (IRS) is of low-cost and energy-efficiency and will be a promising technology for the future wireless communications like sixth generation. To address the problem of conventional directional modulation (DM) that Alice only transmits single confidential bit stream (CBS) to Bob with multiple antennas in a line-of-sight channel, IRS is proposed to create friendly multipaths for DM such that two CBSs can be transmitted from Alice to Bob. This will significantly enhance the secrecy rate (SR) of DM. To maximize the SR (Max-SR), a general non-convex optimization problem is formulated with the unit-modulus constraint of IRS phase-shift matrix (PSM), and the general alternating iterative (GAI) algorithm is proposed to jointly obtain the transmit beamforming vectors (TBVs) and PSM by alternately optimizing one and fixing another. To reduce its high complexity, a low-complexity iterative algorithm for Max-SR is proposed by placing the constraint of null-space (NS) on the TBVs, called NS projection (NSP). Here, each CBS is transmitted separately in the NSs of other CBS and AN channels. Simulation results show that the SRs of the proposed GAI and NSP can approximately double that of IRS-based DM with single CBS for massive IRS in the high signal-to-noise ratio region.
