By cascading lowpass filter using stepped impedance hairpin resonator, the stopband rejection of a bandpass filter can be significantly improved.

• 这种方法通过级联阶跃阻抗发夹线谐振器构成的椭圆函数低通滤波器于带通滤波器的输入／输出端，显著改善了后者的阻带抑制特性。