Design of Balanced Dual-Band Bandpass Filter with Self-Feedback Structure

ETRI Journal

关键词: common-mode suppression;    open-loop resonator;    SIR;    dual-band;    Balanced;   

Others  :  1185805
DOI  :  10.4218/etrij.09.0209.0062

【 摘 要 】

A balanced dual-band bandpass filter based on λ/2 stepped-impedance resonators and open-loop resonators is proposed in this letter. By employing a type of self-feedback structure, an extra transmission zero is introduced near the common-mode resonance frequency, and the common-mode signal is suppressed. The measured results indicate that the filter can operate in 2.46 GHz and 5.6 GHz bands, and the insertion loss is 1.85 dB and 1.9 dB, respectively. Also, better common-mode suppression is achieved.

   

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