We propose a theoretical mechanism and new coding strategy to realize extremely accurate manipulations of nonlinear electromagnetic harmonics in ultrawide frequency band based on a time-domain digital coding metasurface (TDCM). Using the proposed mechanism and coding strategy, we design and fabricate a millimeter-wave (mmWave) TDCM, which is composed of reprogrammable meta-atoms embedded with positive-intrinsic-negative diodes. By controlling the duty ratios and time delays of the digital coding sequences loaded on a TDCM, experimental results show that both amplitudes and phases of different harmonics can be engineered at will simultaneously and precisely in broad frequency band from 22 to 33 GHz, even when the coding states are imperfect, which is in good agreement with theoretical calculations. Based on the fabricated high-performance TDCM, we further propose and experimentally realize a large-capacity mmWave wireless communication system, where 256 quadrature amplitude modulation, along with other schemes, is demonstrated. The new wireless communication system has a much simpler architecture than the currently used mmWave wireless systems, and hence can significantly reduce the hardware cost. We believe that the proposed method and system architecture can find vast application in future mmWave and terahertz-wave wireless communication and radar systems.

中文翻译：

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通过时域数字编码超表面对谐波幅度和相位进行精确和宽带操作以达到 256 QAM 毫米波无线通信

我们提出了一种理论机制和新的编码策略，以实现基于时域数字编码超表面（TDCM）的超宽频带非线性电磁谐波的极其精确的操作。使用所提出的机制和编码策略，我们设计和制造了一种毫米波 (mmWave) TDCM，它由嵌入正-本征-负二极管的可重编程元原子组成。通过控制加载在 TDCM 上的数字编码序列的占空比和时间延迟，实验结果表明，即使在 22 至 33 GHz 的宽频带内，不同谐波的幅度和相位都可以同时且精确地进行设计。编码状态不完善，与理论计算吻合较好。基于制造的高性能TDCM，我们进一步提出并通过实验实现了一个大容量毫米波无线通信系统，其中演示了 256 正交幅度调制以及其他方案。新的无线通信系统的架构比目前使用的毫米波无线系统简单得多，因此可以显着降低硬件成本。我们相信，所提出的方法和系统架构可以在未来的毫米波和太赫兹波无线通信和雷达系统中找到广泛的应用。因此可以显着降低硬件成本。我们相信，所提出的方法和系统架构可以在未来的毫米波和太赫兹波无线通信和雷达系统中找到广泛的应用。因此可以显着降低硬件成本。我们相信，所提出的方法和系统架构可以在未来的毫米波和太赫兹波无线通信和雷达系统中找到广泛的应用。