並列摘要
In this thesis, the parallel coupled lines are used to design the microstrip bandpass filters. The main objectives of this study are to improve the selectivity and to suppress the spurious responses of bandpass filters. By suitably introducting the cross-coupling path in the filter circuit, multiple transmission zeros may be generated to improve the filter selectivity. The filters based on quarter-wavelength coupled line have spurious passbands at odd-multiples of passband center frequency. In this study, the coupled-line sections are made shorter than quarter wavelength so that the spurious response may be suppressed. The next spurious passband then appears around five times the center frequency.
參考文獻
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