RF on-chip LC passive bandpass filter based on GaAs MMIC technology

The design and fabrication of a novel RF on-chip LC passive bandpass filter at S-band (2-4 GHz) based on using an LC passive lowpass filter and two DC-blocking capacitors are presented. The filter is accomplished with GaAs MMIC technology. Measurement results show that the quality factor (Q) of a 3 nH planar spiral MMIC inductor is 13.8 at 6.8 GHz and the self-resonant frequency is 15.5 GHz. The measured centre frequency of the bandpass filter shows agreement with the design performance and the contrast is 3.3%, the insertion loss of the filter is 6.7 dB at the centre frequency, and Q is 6.5.