In this article, the oversized substrate-integrated waveguide (OS-SIW) is proposed, analyzed, and experimentally demonstrated. The physical parameters and the effect of material surface roughness on the attenuation and the SIW power capability lead to the exploitation of wider and thicker waveguides, as an alternative to enhance the power-handling capability (PHC) and reduce the losses. The resulting oversized waveguide is a guide whose width or thickness is greater than that of the SIW, which is sized to support only the TE10 mode in the operating band. An SIW-to-OS-SIW transition has been designed to allow the component characterization in the W-band. The proposed transition allows to propagate only the desired mode TE10 in the OS-SIW and prevent the higher mode propagation. The experimental results of the manufactured prototypes accord well with the simulations in terms of power handling and transmission losses. The proposed OS-SIW line shows lower attenuation (1.5 Np/m) than a standard SIW (3 Np/m) or a microstrip line (about 3.7 Np/m). However, the OS-SIW 5a has achieved an average power of 90 W at 90 GHz. The investigated OS-SIW configuration offers high PHC, low losses, and easy integration into high-power millimeter-wave systems.

中文翻译：

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用于高功率毫米波系统的超大基板集成波导

在本文中，提出、分析并实验证明了超大尺寸衬底集成波导 (OS-SIW)。物理参数和材料表面粗糙度对衰减和 SIW 功率能力的影响导致开发更宽和更厚的波导，作为增强功率处理能力 (PHC) 和减少损耗的替代方案。由此产生的超大波导是一个宽度或厚度大于 SIW 的波导，SIW 的尺寸仅支持工作频段中的 TE10 模式。SIW 到 OS-SIW 的转换被设计为允许在 W 波段中进行组件表征。提议的转换允许在 OS-SIW 中仅传播所需的模式 TE10，并防止更高的模式传播。制造的原型的实验结果在功率处理和传输损耗方面与模拟非常吻合。建议的 OS-SIW 线显示出比标准 SIW (3 Np/m) 或微带线（约 3.7 Np/m）更低的衰减（1.5 Np/m）。然而，OS-SIW 5a 在 90 GHz 下实现了 90 W 的平均功率。所研究的 OS-SIW 配置具有高 PHC、低损耗和易于集成到高功率毫米波系统的特点。