In this study, an ultra-compact meandered grounding resonator is proposed to design two millimetre wave bandpass filters (BPFs) in a standard 0.13-µm silicon-germanium (Bi)-complementary metal oxide semiconductor (CMOS) technology. The fundamental second-order prototype, namely BPF-I, consists of a pair of proposed resonators and a pair of grounded metal-insulator-metal (MIM) capacitors. To better understand the principle of the second-order BPF-I, an equivalent LC-circuit model and theoretical analysis method are presented in this study. Based on BPF-I, the second-order BPF-II is proposed by adding the additional two pairs of MIM capacitors to improve the frequency selectivity, by means of introducing a transmission zero at lower stopband. Finally, both of the two second-order BPFs are fabricated. The measured results show a good agreement with the full-wave simulation results. The insertion loss of the first BPF-I is 1.79 dB at the centre frequency of 46.6 GHz, and the fractional bandwidth is up to 96.5%. The second BPF-II has a centre frequency at 46.8 GHz with a fractional bandwidth of 94.1%. The minimum insertion loss is 2.08 dB and the lower stopband attenuation is up to 42.7 dB. Moreover, the die sizes of the two compact BPFs, excluding the test pads, are only 0.0197 mm ² (0.104 × 0.190 mm ² ).

中文翻译：

---

紧凑的片上毫米波带通滤波器，采用0.13-μm（Bi）-CMOS技术的弯曲接地谐振器

在这项研究中，提出了一种超紧凑的弯曲接地谐振器，以采用标准的0.13 µm硅锗（Bi）互补金属氧化物半导体（CMOS）技术设计两个毫米波带通滤波器（BPF）。基本的二阶原型，即BPF-1，由一对建议的谐振器和一对接地的金属-绝缘体-金属（MIM）电容器组成。为了更好地理解二阶BPF-I的原理，本研究提出了等效的LC电路模型和理论分析方法。基于BPF-I，通过在较低的阻带处引入传输零，通过添加额外的两对MIM电容器来提高频率选择性，提出了二阶BPF-II。最后，两个二阶BPF均被制造。测量结果与全波模拟结果吻合良好。在中心频率46.6 GHz处，第一BPF-1的插入损耗为1.79 dB，并且小数带宽高达96.5％。第二个BPF-II的中心频率为46.8 GHz，分数带宽为94.1％。最小插入损耗为2.08 dB，下阻带衰减高达42.7 dB。此外，除测试焊盘外，两个紧凑型BPF的芯片尺寸仅为0.0197 mm ²（0.104×0.190 mm ² ）。