Dual‐band bandstop filter using stub‐loaded resonators with sharp rejection characteristic.

Dual‐band bandstop filters using open‐circuited stub‐loaded resonators are presented. The first and second resonant frequencies of the open‐circuited stub‐loaded resonator can be flexibly controlled by tuning the length and position of the open‐circuited stub. To illustrate the concept, a dual‐band bandstop filter has been designed, fabricated and measured. The prototype of the dual‐band bandstop filter achieved attenuation of 42 and 44 dB at 2.4 and 5.2 GHz. [ABSTRACT FROM AUTHOR]