A UWB Bidirectional Rectangular Ring Antenna Fed by CDM with a Rod and Ridges for Constant Beam Direction

<table class="table-group" id="tab1"><tr><td><table class="table"><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr class="thead"><td align="left">Parameter</td><td align="center">Physical size</td><td align="center">Electrical size (<svg height="10.8125" id="M88" style="vertical-align:-0.20064pt" version="1.1" viewbox="0 0 8.5749998 10.8125" width="8.5749998" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,10.8125)">
<g transform="translate(72,-63.35)">
<text transform="matrix(1,0,0,-1,-71.95,63.6)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝜆</tspan>
</text>
</g>
</g>
</svg>)</td></tr><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr><td align="left"><span style="width: 7.9749999px;"><svg height="7.1750002" id="M89" style="vertical-align:-0.1254pt" version="1.1" viewbox="0 0 7.9749999 7.1750002" width="7.9749999" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,7.175)">
<g transform="translate(72,-66.26)">
<text transform="matrix(1,0,0,-1,-71.95,66.44)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑎</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">4.0 cm</td><td align="center">0.400</td></tr><tr><td align="left"><span style="width: 7.4749999px;"><svg height="10.7375" id="M90" style="vertical-align:-0.13794pt" version="1.1" viewbox="0 0 7.4749999 10.7375" width="7.4749999" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,10.7375)">
<g transform="translate(72,-63.41)">
<text transform="matrix(1,0,0,-1,-71.95,63.6)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑏</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">2.8 cm</td><td align="center">0.280</td></tr><tr><td align="left"><span style="width: 7.3874998px;"><svg height="7.1875" id="M91" style="vertical-align:-0.13794pt" version="1.1" viewbox="0 0 7.3874998 7.1875" width="7.3874998" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,7.1875)">
<g transform="translate(72,-66.25)">
<text transform="matrix(1,0,0,-1,-71.95,66.44)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑐</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">1.5 cm</td><td align="center">0.150</td></tr><tr><td align="left"><span style="width: 11.325px;"><svg height="11.0375" id="M92" style="vertical-align:-3.22282pt" version="1.1" viewbox="0 0 11.325 11.0375" width="11.325" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,11.0375)">
<g transform="translate(72,-63.17)">
<text transform="matrix(1,0,0,-1,-71.95,66.44)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑠</tspan>
</text>
<text transform="matrix(1,0,0,-1,-66.45,63.31)">
<tspan style="font-size: 8.75px; " x="0" y="0">𝑙</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">1.1 cm</td><td align="center">0.110</td></tr><tr><td align="left"><span style="width: 12.8125px;"><svg height="11.025" id="M93" style="vertical-align:-3.21404pt" version="1.1" viewbox="0 0 12.8125 11.025" width="12.8125" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,11.025)">
<g transform="translate(72,-63.18)">
<text transform="matrix(1,0,0,-1,-71.95,66.44)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑠</tspan>
</text>
<text transform="matrix(1,0,0,-1,-66.45,63.31)">
<tspan style="font-size: 8.75px; " x="0" y="0">𝑢</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">4.0 mm</td><td align="center">0.040</td></tr><tr><td align="left"><span style="width: 12.2125px;"><svg height="11.05" id="M94" style="vertical-align:-3.2316pt" version="1.1" viewbox="0 0 12.2125 11.05" width="12.2125" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,11.05)">
<g transform="translate(72,-63.16)">
<text transform="matrix(1,0,0,-1,-71.95,66.44)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑟</tspan>
</text>
<text transform="matrix(1,0,0,-1,-66.85,63.31)">
<tspan style="font-size: 8.75px; " x="0" y="0">𝑐</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">7.7 mm</td><td align="center">0.077</td></tr><tr><td align="left"><span style="width: 11.0625px;"><svg height="16.475" id="M95" style="vertical-align:-4.74141pt" version="1.1" viewbox="0 0 11.0625 16.475" width="11.0625" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,16.475)">
<g transform="translate(72,-58.82)">
<text transform="matrix(1,0,0,-1,-71.95,63.6)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑙</tspan>
</text>
<text transform="matrix(1,0,0,-1,-67.97,60.47)">
<tspan style="font-size: 8.75px; " x="0" y="0">𝑝</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">6.0 mm</td><td align="center">0.060</td></tr><tr><td align="left"><span style="width: 14.95px;"><svg height="14.8" id="M96" style="vertical-align:-3.21404pt" version="1.1" viewbox="0 0 14.95 14.8" width="14.95" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,14.8)">
<g transform="translate(72,-60.16)">
<text transform="matrix(1,0,0,-1,-71.95,63.41)">
<tspan style="font-size: 12.50px; " x="0" y="0">ℎ</tspan>
</text>
<text transform="matrix(1,0,0,-1,-64.74,60.28)">
<tspan style="font-size: 8.75px; " x="0" y="0">𝑢</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">3.0 mm</td><td align="center">0.030</td></tr><tr><td align="left"><span style="width: 13.4625px;"><svg height="14.8125" id="M97" style="vertical-align:-3.22282pt" version="1.1" viewbox="0 0 13.4625 14.8125" width="13.4625" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,14.8125)">
<g transform="translate(72,-60.15)">
<text transform="matrix(1,0,0,-1,-71.95,63.41)">
<tspan style="font-size: 12.50px; " x="0" y="0">ℎ</tspan>
</text>
<text transform="matrix(1,0,0,-1,-64.74,60.28)">
<tspan style="font-size: 8.75px; " x="0" y="0">𝑙</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center">3.0 mm</td><td align="center">0.030</td></tr><tr class="table-tr"><td colspan="3"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

International Journal of Microwave Science and Technology

tab1

Table 1

Table 1: A UWB Bidirectional Rectangular Ring Antenna Fed by CDM with a Rod and Ridges for Constant Beam Direction 