This letter proposes a compact low-pass filter (LPF) using dielectric filled capacitor based on the substrate integrated suspended line (SISL) platform. A dielectric filled capacitor with high capacitance density is presented for the first time. Using this type of capacitor, a three-order lumped element LPF with a cutoff frequency of 120 MHz is designed, fabricated, and tested. The measured results agree with the simulated ones. The circuit size of the implemented SISL LPF is only $0.005\,\,\lambda \text{g}\,\,\times0.013\,\,\lambda \text{g}$ , which is very small when compared to the state of art. The measured insertion loss of SISL LPF in the passband is 0.12 dB and the stopband is from 0.35 to 2.27 GHz with a suppression level greater than 20 dB. A seven-order LPF is also designed to further demonstrate the good property of the proposed capacitor.

中文翻译：

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在 SISL 平台上使用电介质填充电容器的紧凑型低通滤波器

这封信提出了一种基于基板集成悬浮线 (SISL) 平台的使用介质填充电容器的紧凑型低通滤波器 (LPF)。首次提出了具有高电容密度的介质填充电容器。使用这种电容器，设计、制造和测试了截止频率为 120 MHz 的三阶集总元件 LPF。测量结果与模拟结果一致。实现的 SISL LPF 的电路尺寸仅为 $0.005\,\,\lambda \text{g}\,\,\times0.013\,\,\lambda \text{g}$ ，与最先进的技术。SISL LPF 在通带中测得的插入损耗为 0.12 dB，阻带为 0.35 至 2.27 GHz，抑制电平大于 20 dB。