Polymeric foams are one of the new candidates for the insulation of signal cables due to their effect on decreasing the signal loss. Accordingly, the effect of using foamed polyethylene in the dielectric section of coaxial cables on their transmission properties is investigated in this study. The samples were coaxial cables with identical properties in all sections except the dielectric part which had different foam structures. The expansion ratio and structural properties including cell size and cell density of the foams were measured. In the next step, the attenuation along the cable was determined both experimentally and theoretically. Due to the results, attenuation showed up to 38.46% reduction by foaming the dielectric compared to the solid dielectric sample. The experimental results showed good accordance with theoretical data. However, in higher frequencies, difference between these two approaches rose. A comparison of experimental and theoretical data also revealed that the expansion ratio of the foam is not the only effective parameter on the attenuation of cable. There are two other major factors: cell density and open‐cell content. High cell density foams show a lower attenuation, while in foams with high open‐cell content, a major increase was observed in the attenuation.

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研究泡沫特性对使用发泡聚乙烯电介质的同轴电缆衰减的影响

聚合泡沫材料由于可降低信号损耗而成为信号电缆绝缘的新候选材料之一。因此，在本研究中研究了在同轴电缆的介电部分使用发泡聚乙烯对其传输性能的影响。样品是在所有部分中具有相同特性的同轴电缆，除了介电部分具有不同的泡沫结构。测量泡沫的膨胀率和结构性质，包括孔尺寸和孔密度。下一步，通过实验和理论确定沿电缆的衰减。由于该结果，与固体电介质样品相比，通过使电介质发泡，衰减显示最多可降低38.46％。实验结果与理论数据吻合良好。然而，在较高的频率下，这两种方法之间的差异会增加。实验和理论数据的比较还表明，泡沫的膨胀率并不是电缆衰减的唯一有效参数。还有其他两个主要因素：孔密度和开孔含量。高孔密度泡沫显示较低的衰减，而在高开孔含量的泡沫中，观察到衰减显着增加。