Millimeter-Wave Bandpass Filter Based on Spiral Resonators and DGS Using SiGe BiCMOS Technology
Yiqun Liu, Xiaoyu Weng, Kai‐Da Xu
Abstract
A new ultra-compact millimeter-wave on-chip bandpass filter (BPF) is presented based on two spiral resonators and a defected ground structure (DGS). For investigating the working mechanism of the proposed BPF, an <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> equivalent circuit is constructed, and then the corresponding transmission zeros (TZs) are calculated in order to make the filter be quickly optimized with the guidance of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> equivalent circuit. Finally, the BPF is fabricated using 0.13- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> SiGe BiCMOS technology for demonstration. The measured results show that the fabricated BPF has a center frequency at 70.65 GHz with a bandwidth of 29.3%. The chip area of the BPF, excluding testing pads, is only 0.0288 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .