Decoupling of Multifrequency Dipole Antenna Arrays for Microwave Imaging Applications

<table>Near-field measurements of the surface illumination when the dipoles resonating are radiating in free space(left column) and with the superstrate (right column). (a), (b) Resonant frequency at <svg height="17.35" id="M80" style="vertical-align:-4.11684pt" version="1.1" viewbox="0 0 34.462502 17.35" width="34.462502" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,10.975,17.2)"><path d="M729 650v-28q-62 -5 -76 -19.5t-14 -75.5v-404q0 -62 13.5 -76t75.5 -19v-28h-268v28q65 5 79.5 19t14.5 76v199h-341v-199q0 -62 14 -76t76 -19v-28h-263v28q61 5 74.5 19t13.5 76v404q0 62 -14 76t-76 19v28h259v-28q-58 -5 -71 -19t-13 -76v-162h341v162
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</svg>. (c), (d) Resonant frequency at <svg height="17.35" id="M81" style="vertical-align:-4.11684pt" version="1.1" viewbox="0 0 35.625 17.35" width="35.625" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,10.975,17.2)"><path d="M495 163l30 -6q-19 -99 -36 -157h-453v28q63 5 77.5 20t14.5 78v400q0 63 -13 77t-75 19v28h261v-28q-61 -5 -74.5 -19t-13.5 -77v-395q0 -41 5 -59t18 -25q24 -13 96 -13q85 0 112 31q30 33 51 98z" id="x4C"></path></g><g transform="matrix(.012,-0,0,-.012,17.377,17.2)"><path d="M631 18l-4 -26q-24 0 -35 1q-57 3 -92.5 23t-69.5 68q-21 30 -101 160q-13 22 -30.5 31t-54.5 9h-32v-159q0 -63 14 -77.5t74 -19.5v-28h-262v28q62 5 76 19.5t14 77.5v402q0 62 -13 76t-73 19v28h248q109 0 159 -34q67 -42 67 -131q0 -115 -127 -172q27 -52 89 -144
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</svg></table>

International Journal of Antennas and Propagation

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Figure 5

Figure 5: Decoupling of Multifrequency Dipole Antenna Arrays for Microwave Imaging Applications 