دانلود مقاله انعکاس هوشمند به حداکثر رساندن نرخ محرمانگی MIMO
چکیده
مقدمه
حداکثر کردن نرخ رازداری با کمک IRS
نتایج عددی
نتیجه گیری
منابع
Abstract
Introduction
IRS-aided secrecy rate maximization
Numerical results
Conclusion
References
چکیده
این مقاله به حداکثر رساندن نرخ رازداری MIMO به کمک سطح بازتابی هوشمند می‌پردازد. ما بهینه سازی متناوب را برای به حداکثر رساندن میزان محرمانه بودن کانال های استراق سمع MIMO اعمال می کنیم. ما ابتدا راه‌حل شکل بسته را برای هر زیرمسئله بهینه‌سازی ضریب واحد بازتابی ارائه می‌کنیم و نشان می‌دهیم که دنباله ایجاد شده توسط روش نزول مختصات به یک نقطه ثابت از مسئله بهینه‌سازی اصلی همگرا می‌شود. نتایج عددی نشان می‌دهد که سطح بازتابی هوشمند به طور قابل‌توجهی نرخ محرمانگی را در کانال‌های استراق سمع MIMO افزایش می‌دهد.
توجه! این متن ترجمه ماشینی بوده و توسط مترجمین ای ترجمه، ترجمه نشده است.
Abstract
This paper considers the intelligent reflecting surface-aided MIMO secrecy rate maximization. We apply the alternating optimization to maximize the secrecy rate of the MIMO wiretap channels. We first provide the closed-form solution to each subproblem of optimizing reflecting unit coefficient and show that the sequence generated by the coordinate descent method converges to a stationary point of the main optimization problem. Numerical results show that the intelligent reflecting surface significantly increases secrecy rates in MIMO wiretap channels.
Introduction
Intelligent reflecting surface (IRS) is a promising solution that can cost-effectively and energy-efficiently improve wireless communication capacity by adjusting a large number of passive reflecting units to appropriately change signal propagation [1]. IRS implemented with conventional reflectarray antennas or software defined metamaterials can achieve passive beamforming for directional signal enhancement or nulling by adjusting reflecting unit phase and amplitude. Recently, IRS has been considered in physical layer security and MISO/MIMO systems to improve wireless communication capabilities [2]. In addition, the benefits of joint non-orthogonal multiple access and IRS were investigated [3]. However, in scenarios where the channels of the legitimate communication link and the channel of the eavesdropping link are spatially highly correlated, the achievable secrecy rate may be very limited.
Conclusion
In this paper, we presented closed-form expressions for the optimal IRS coefficient in the IRS-aided MIMO wiretap channel. We transformed the IRS coefficient optimization problem into an equivalent linear-fractional optimization under amplitude constraints, which admits the closed-form optimal solution. In the literature, many IRS optimization problems usually have been numerically solved approximately using semidefinite relaxation or majorization minimization. We first provided the closed-form expression for optimal reflection coefficient without resorting to any numerical optimization for IRS-aided MIMO secrecy rate maximization. Thus, our derived solution is much better in the sense that it is exact and can be computed with much lower complexity and with more numerical stability.