Analysis and Design of Bandpass Filters with Ultra-Wide Reflectionless Range in GaAs Technology

In this work, two reflectionless bandpass filters based on lumped elements were designed and fabricated using 0.25um GaAs technology, which realizing 60GHz ultra-wide reflectionless frequency range. Filter A consists a third-order reflectionless low-pass filter and a third-order reflectionless high-pass filter. Measured results show the bandpass filter demonstrates an insertion loss below 3.5 dB within the 24~34 GHz frequency range and a return loss exceeding 13.8 dB over the 0~60 GHz frequency band. Meanwhile, the dimensions of the fabricated filter circuit are just 420 μm * 688 μm. Filter B is built upon Filter A by increasing the order of the low-pass structure, thereby optimizing frequency selectivity. The design results demonstrate the excellent performance of the on-chip reflectionless filter achieved in the high-frequency band.