Investigation of Compact Balun-Bandpass Filter Using Folded Open-Loop Ring Resonators and Microstrip Lines

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</svg>-parameters and (b) phase/amplitude difference of the designed balun BPF with about 100-<svg height="11.425" id="M50" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 12.9875 11.425" width="12.9875" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> balanced impedance.</table>

Mathematical Problems in Engineering

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Figure 8

Figure 8: Investigation of Compact Balun-Bandpass Filter Using Folded Open-Loop Ring Resonators and Microstrip Lines 