Heatsinks are widely utilized to maintain the temperature of the electronic circuit components on the printed circuit board (PCB) within a certain range. Even they are thermally used for maximum cooling; they can also act as a source of electromagnetic (EM) radiation, causing EM interference (EMI) to their surrounding elements in certain cases. In this article, the heatsinks with various fin types such as plate‐fin, parabole‐plate fin, square‐pin fin, and circular‐pin fin are designed and fabricated to investigate EMI and thermal performances. The simulated and measured results of the reflection coefficient and normalized radiation pattern are obtained and compared in the S‐C band (2‐8 GHz). The dimension of the heatsink base regarding the patch antenna determines the first resonance frequency (4.75 GHz) while its height regarding the monopole antenna determines the second resonance frequency (6.75 GHz). It is aimed to investigate the effect of fin types of them and their orientation on radiated emission (RE) on the PCB. If the operating frequencies of the circuit elements near the heatsink are in the 2 to 3.4 GHz, 4.7 to 5.6 GHz, 5.6 to 6.15 GHz, and 6.85 to 8 GHz, it is preferable to use pin‐fin type instead of plate fins to reduce the RE from the heatsinks. However, in the 6.15 to 6.85 GHz, plate fins types should be preferred. All heatsinks regardless of fin types in the 2 to 2.2 GHz, 3.6 to 5.6 GHz, and 6.6 to 7.2 GHz should be located as horizontal. However, for 2.2 to 3.6 GHz, 5.6 to 6.6 GHz, and 7.6 to 8 GHz frequency bands, they should be located as vertical. Consequently, while pin‐fin type heatsink is preferred in 50% of the entire frequency band, it is better to use plate‐fin type heatsink in 35% of the band. Regardless of the type of heatsink used, it is significant to place the heatsink horizontally and vertically in 35% and 34% of the frequency band, respectively.

中文翻译：

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散热片的鳍片类型对S‐C频段印刷电路板上的辐射发射的影响

散热器被广泛用于将印刷电路板（PCB）上的电子电路组件的温度保持在一定范围内。甚至将它们用于最大冷却。它们还可以充当电磁（EM）辐射源，在某些情况下会对周围的元件造成EM干扰（EMI）。在本文中，设计并制造了具有各种翅片类型的散热器，例如板翅，抛物板翅片，方钉翅片和圆钉翅片，以研究EMI和热性能。获得了反射系数和归一化辐射方向图的仿真和测量结果，并在S–C频段（2–8 GHz）中进行了比较。散热器底座相对于贴片天线的尺寸确定了第一谐振频率（4。75 GHz），而其相对于单极天线的高度决定了第二谐振频率（6.75 GHz）。目的是研究鳍片类型及其方向对PCB上辐射发射（RE）的影响。如果散热器附近的电路元件的工作频率在2到3.4 GHz，4.7到5.6 GHz，5.6到6.15 GHz和6.85到8 GHz，最好使用针鳍式代替板式鳍以减少散热器的RE。但是，在6.15至6.85 GHz中，应首选板翅片类型。无论2至2.2 GHz，3.6至5.6 GHz和6.6至7.2 GHz的鳍片类型如何，所有散热器都应水平放置。但是，对于2.2至3.6 GHz，5.6至6.6 GHz和7.6至8 GHz频带，它们应垂直放置。所以，虽然最好在整个频带的50％中使用针翅式散热器，但最好在频带的35％中使用板翅式散热器。无论使用哪种散热器，都必须将散热器水平和垂直放置在频带的35％和34％内，这一点很重要。