Microstrip cascade trisection filter

A new configuration of odd-degree cascade trisection bandpass filter realized by combining a microstrip hairpin resonator and /spl lambda//2-line open-circuited resonator is proposed. The general asymmetric Chebyshev function is used to synthesize the cascade trisection prototype. A five-pole microstrip cascade trisection bandpass filter with two asymmetrically prescribed transmission zeros located on opposite of the passband is designed and fabricated. The experimental result matches well with the theory.