Title :
A Compact Via-Hole-Free Hairpin-Comb Bandpass Filter With 50-dB Stopband Suppression Up to Quadruple Passband Frequency
Author :
Chou, Cheng-Yu ; Chang, Sheng-Fuh ; Chen, Yi-Ming
Author_Institution :
Dept. of Electr. Eng., Nat. Chung Cheng Univ., Chiayi
Abstract :
A compact microstrip hairpin-comb bandpass filter with strong spurious-band suppression up to a quadruple of passband central frequency is presented. The open-circuited stepped-impedance resonators are folded in a U-shape and aligned in the same orientation such that the filter has advantages of smaller filter length and free of via-hole grounds. The input and output tapped-transformer feeding scheme is employed for impedance match and for higher stopband suppression. A demonstrated 2.45-GHz hairpin-comb bandpass filter achieves measurement results of 50-dB stopband rejection up to 10 GHz with a maximum of 80 dB suppression from 6.5 to 7.5 GHz.
Keywords :
UHF filters; band-pass filters; band-stop filters; comb filters; impedance matching; interference suppression; microstrip filters; resonator filters; frequency 2.45 GHz; frequency 6.5 GHz to 7.5 GHz; hairpin-comb bandpass filter; impedance match; input tapped-transformer feeding scheme; microstrip bandpass filter; output tapped-transformer feeding scheme; quadruple passband frequency; spurious-band suppression; stepped-impedance resonators; stopband rejection; stopband suppression; Band pass filters; Capacitors; Circuits; Current measurement; Frequency; Impedance; Microstrip filters; Microwave communication; Passband; Resonator filters; hairpin-comb; microstrip; stepped-impedance resonator;
Conference_Titel :
Microwave Conference, 2007. APMC 2007. Asia-Pacific
Conference_Location :
Bangkok
Print_ISBN :
978-1-4244-0748-4
Electronic_ISBN :
978-1-4244-0749-1
DOI :
10.1109/APMC.2007.4554749
