A Defected Ground Structure without Ground Contact Problem and Application to Branch Line Couplers

<table>DGS line using the double-layered substrate. Area “<svg height="11.4625" id="M6" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 12.5875 11.4625" width="12.5875" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,11.4)"><path d="M716 28l-8 -28h-254l8 28q55 5 66 17.5t5 47.5l-30 145h-232l-74 -138q-21 -43 -11 -54.5t72 -17.5l-6 -28h-235l8 28q53 7 73.5 21t53.5 70l319 540l33 8q6 -43 33 -176l80 -381q10 -49 26.5 -63t72.5 -19zM495 281l-49 264h-2l-149 -264h200z" id="x1D434"></path></g>
</svg>” completely contains the DGS patterns.</table>

International Journal of Antennas and Propagation

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Figure 2

Figure 2: A Defected Ground Structure without Ground Contact Problem and Application to Branch Line Couplers 