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A narrow‐band bandpass filter (BPF) based on parallel coupled lines and shorted stubs with very wide upper stopband has been presented. The transmission coefficient and reflection coefficient of the proposed BPF are straightforwardly derived via the input impedances using odd‐ and even‐mode analysis method. The calculation results illustrate that two narrow passbands with very high frequency ratio of the upper‐band to lower‐band center frequencies can be realized, which is significantly suitable to design a narrow‐band BPF with very wide upper stopband. To verify the proposed design idea, a narrow‐band BPF example was designed and experimentally characterized, whose measured in‐band return loss is >30 dB with center frequency at 1.76 GHz. The measured upper stopband is up to 14.34 GHz with the rejection levels of over 20 dB. [ABSTRACT FROM AUTHOR]