Metal curving or metal denting is usually an unwanted phenomenon in the printed circuit board (PCB) process. However, curved metal could provide some benefits to enhance performance of radio frequency components. In this article, an approach is proposed to develop a double-curved metal (DCM) in a multilayer PCB process by allocating a metal upon an air cavity and then laminating with buffer layers under suitable pressure and temperature. This approach could increase the degree of freedom on radio frequency component design in PCB process. Based on this approach, a millimeter-wave (mmWave) aperture-coupled patch antenna is produced with the improved characteristics of high gain, wide bandwidth, and compact size. Prototypes of the proposed antenna are designed, manufactured, measured, analyzed, dissected, and observed under a metallographic microscope. The measurements and simulations are in good agreement and demonstrate that the proposed antenna achieves a maximum gain of 8 dBi over an operating bandwidth of 27.4-34.2 GHz. Compared with an aperture-coupled patch antenna with a flat metal, the fractional bandwidth of that with a double-curved metal is enhanced by a factor of two.

中文翻译：

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多层印刷电路板中的双曲金属可增强毫米波贴片天线的带宽


金属弯曲或金属凹痕通常是印刷电路板 (PCB) 工艺中的不良现象。然而，弯曲金属可以提供一些好处来增强射频组件的性能。本文提出了一种在多层 PCB 工艺中开发双曲金属 (DCM) 的方法，即在气腔上分配金属，然后在适当的压力和温度下与缓冲层层压。这种方法可以增加 PCB 工艺中射频元件设计的自由度。基于这种方法，产生了毫米波（mmWave）孔径耦合贴片天线，具有高增益、宽带宽和紧凑尺寸的改进特性。所提出的天线原型经过设计、制造、测量、分析、解剖并在金相显微镜下观察。测量和仿真非常一致，并表明所提出的天线在 27.4-34.2 GHz 的工作带宽上实现了 8 dBi 的最大增益。与采用扁平金属的孔径耦合贴片天线相比，采用双曲金属的孔径耦合贴片天线的分数带宽提高了两倍。