Design of an Integrated on-chip bandpass filter using inverse-coupled resonator

This paper presents an Integrated on-chip bandpass filter design using an inverse-coupled resonator. Both the resonator and bandpass filter are designed and fabricated in a standard silicon-germanium technology. The designed resonator is based on a unique structure, which consists of two broadside-coupled meander lines with opposite orientation. Using this structure along with capacitors, the bandpass filter is designed. The measured results show that the BPF has a center frequency at 31 GHz and insertion loss of 2.5 dB. The chip size of the BPF, excluding the pads, is only 0.024 mm² (0.09 × 0.27 mm²), which the most compact one among the other state-of-the-art designs.