In this paper, we propose and develop a novel reconfigurable bandpass filter based on microstrip LC resonators. The equivalent circuit model of the proposed filter is presented. The filter can be reconfigured by tuning the capacitance of the microstrip LC resonators. A reconfigurable bandpass filter based on semiconductor varactor diode loaded microstrip LC resonators with a tuning range of 2.496 GHz to 2.937 GHz, and a fractional bandwidth of 6.3% to 8.2% is demonstrated, and the measured insertion loss is 1.7 dB to 3.8 dB. The out-band rejection is better than 25 dB up to 10 GHz.
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