Ku-band Bandpass Filter Design with Compact Size and Broad Stopband by pHEMT Process

In this research a bandpass filter was designed which has a broad stopband and compact dimension and realized by the microstrip lines of 0.15-μm GaAs pHEMT fabrication process. To reach a wide stopband, designs were conducted to suppress the two major harmonic frequency peaks. This bandpass filter has a stepped impedance resonator with slow-wave coupling and cross coupled structure. The passband is designed at 13.5 GHz with a 11% bandwidth. The ADS software was adopted for the simulation of circuit design. The insertion loss of the passband is only 2.6 dB and the device has shown a compact dimension.