In this paper, we propose a novel parameter-free Landweber iteration (LI) method to improve the robustness of a beamformer based on the LI algorithm and the L-curve criterion. The critical aspect of the proposed method is the automatic parameter selection procedure, which determines the iteration stop number in a scenario-dependent manner. This parameter-free method can flexibly adapt to different communication environments. To further improve the computational efficiency, an accelerated parameter-free LI method is also proposed that incorporates the Newton iteration into the LI algorithm without compromising the robustness of the beamformer. Numerical experiments demonstrate the effectiveness of the proposed beamformer.

中文翻译：

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鲁棒自适应波束成形的无参数Landweber迭代法

在本文中，我们提出了一种新的无参数 Landweber 迭代 (LI) 方法，以提高基于 LI 算法和 L 曲线准则的波束形成器的鲁棒性。所提出方法的关键方面是自动参数选择程序，它以依赖于场景的方式确定迭代停止数。这种无参数方式可以灵活适应不同的通信环境。为了进一步提高计算效率，还提出了一种加速的无参数 LI 方法，该方法将牛顿迭代合并到 LI 算法中，而不会影响波束形成器的鲁棒性。数值实验证明了所提出的波束形成器的有效性。