Harmonic cancellation of parallel-coupled bandpass filter with transmission zero realign method

This paper presents the harmonic cancellation of a 3/sup rd/ order Butterworth response parallel-coupled bandpass filter by introducing periodical grooves. The cancellation was obtained by aligning the transmission zero of the tight coupling (TCg) coupler with the harmonic of the weak coupling (WCg) coupler. The alignment of transmission zero and harmonic… CONTINUE READING