Design of a 20-to-40 GHz bandpass MMIC amplifier

A millimeterwave bandpass MMIC amplifier, which integrates both features of gain amplifier and bandpass filter, is presented. A synthesis method for such amplifier is developed from the image-parameter filter theory. By employing the proposed bandpass amplifier in a receiver, the bulky of chip filter may not be required. An experimental chip fabricated by 0.1 /spl mu/m PHEMT shows 14.2dB gain from 20 to 40 GHz and 60-dB attenuation below 7 GHz and above 60 GHz. This confirms the proposed method and shows the feasibility of the function integration of gain amplifier with bandpass filter in the millimeterwave range.