Fully Distributed Tunable Bandpass Filter Based on <svg style="vertical-align:-4.49648pt;width:124.775px;" id="M1" height="20.85" version="1.1" viewBox="0 0 124.775 20.85" width="124.775" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg"><g transform="matrix(.022,-0,0,-.022,.062,15.188)"><path id="x42" d="M372 352v-2q176 -27 176 -159q0 -99 -95 -151q-73 -40 -196 -40h-221v28q65 5 78.5 19t13.5 76v404q0 63 -12 77t-72 18v28h257q102 0 150 -34q26 -18 41 -48.5t15 -65.5q0 -111 -135 -150zM213 362h47q80 0 117.5 32t37.5 96q0 56 -33 92t-100 36q-41 0 -56 -10
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q-25 23 -56 39q-34 17 -97 38v17q69 21 100 53t31 78q0 103 -99 103q-40 0 -69.5 -19t-56.5 -64z" /></g></svg> Thin-Film Slow-Wave Structure

<table>Picture of the fabricated 3 <i>μ</i>m gap Fishbone bandpass filter under test.</table>

International Journal of Microwave Science and Technology

fig6

Figure 6

Figure 6: Fully Distributed Tunable Bandpass Filter Based on <svg style="vertical-align:-4.49648pt;width:124.775px;" id="M1" height="20.85" version="1.1" viewBox="0 0 124.775 20.85" width="124.775" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg"><g transform="matrix(.022,-0,0,-.022,.062,15.188)"><path id="x42" d="M372 352v-2q176 -27 176 -159q0 -99 -95 -151q-73 -40 -196 -40h-221v28q65 5 78.5 19t13.5 76v404q0 63 -12 77t-72 18v28h257q102 0 150 -34q26 -18 41 -48.5t15 -65.5q0 -111 -135 -150zM213 362h47q80 0 117.5 32t37.5 96q0 56 -33 92t-100 36q-41 0 -56 -10
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q-25 23 -56 39q-34 17 -97 38v17q69 21 100 53t31 78q0 103 -99 103q-40 0 -69.5 -19t-56.5 -64z" /></g></svg> Thin-Film Slow-Wave Structure 

International Journal of Microwave Science and Technology

Fully Distributed Tunable Bandpass Filter Based on Thin-Film Slow-Wave Structure

Figure 6