A Power-Efficient Soft-Output Detector for Spatial-Multiplexing MIMO Communications

<table class="table-group" id="tab3"><tr><td><table class="table"><tr><td class="thead-hr" colspan="5"><hr/></td></tr><tr class="thead"><td align="left"></td><td align="center"><span style="width: 69.137497px;"><svg height="13.25" id="M79" style="vertical-align:-1.95624pt" version="1.1" viewbox="0 0 69.137497 13.25" width="69.137497" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,13.25)">
<g transform="translate(72,-61.4)">
<text transform="matrix(1,0,0,-1,-71.95,63.4)">
<tspan style="font-size: 12.50px; " x="0" y="0">[</tspan>
<tspan style="font-size: 12.50px; " x="4.1634989" y="0">2</tspan>
<tspan style="font-size: 12.50px; " x="10.414999" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="15.616247" y="0">3</tspan>
<tspan style="font-size: 12.50px; " x="21.867746" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="27.081497" y="0">4</tspan>
<tspan style="font-size: 12.50px; " x="33.332996" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="38.534245" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="44.785748" y="0">6</tspan>
<tspan style="font-size: 12.50px; " x="51.037247" y="0">]</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center"><span style="width: 69.137497px;"><svg height="13.25" id="M80" style="vertical-align:-1.95624pt" version="1.1" viewbox="0 0 69.137497 13.25" width="69.137497" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,13.25)">
<g transform="translate(72,-61.4)">
<text transform="matrix(1,0,0,-1,-71.95,63.4)">
<tspan style="font-size: 12.50px; " x="0" y="0">[</tspan>
<tspan style="font-size: 12.50px; " x="4.1634989" y="0">2</tspan>
<tspan style="font-size: 12.50px; " x="10.414999" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="15.616247" y="0">2</tspan>
<tspan style="font-size: 12.50px; " x="21.867746" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="27.081497" y="0">2</tspan>
<tspan style="font-size: 12.50px; " x="33.332996" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="38.534245" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="44.785748" y="0">6</tspan>
<tspan style="font-size: 12.50px; " x="51.037247" y="0">]</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center"><span style="width: 69.137497px;"><svg height="13.25" id="M81" style="vertical-align:-1.95624pt" version="1.1" viewbox="0 0 69.137497 13.25" width="69.137497" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,13.25)">
<g transform="translate(72,-61.4)">
<text transform="matrix(1,0,0,-1,-71.95,63.4)">
<tspan style="font-size: 12.50px; " x="0" y="0">[</tspan>
<tspan style="font-size: 12.50px; " x="4.1634989" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="10.414999" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="15.616247" y="0">2</tspan>
<tspan style="font-size: 12.50px; " x="21.867746" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="27.081497" y="0">2</tspan>
<tspan style="font-size: 12.50px; " x="33.332996" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="38.534245" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="44.785748" y="0">6</tspan>
<tspan style="font-size: 12.50px; " x="51.037247" y="0">]</tspan>
</text>
</g>
</g>
</svg></span></td><td align="center"><span style="width: 69.137497px;"><svg height="13.25" id="M82" style="vertical-align:-1.95624pt" version="1.1" viewbox="0 0 69.137497 13.25" width="69.137497" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,13.25)">
<g transform="translate(72,-61.4)">
<text transform="matrix(1,0,0,-1,-71.95,63.4)">
<tspan style="font-size: 12.50px; " x="0" y="0">[</tspan>
<tspan style="font-size: 12.50px; " x="4.1634989" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="10.414999" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="15.616247" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="21.867746" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="27.081497" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="33.332996" y="0">,</tspan>
<tspan style="font-size: 12.50px; " x="38.534245" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="44.785748" y="0">6</tspan>
<tspan style="font-size: 12.50px; " x="51.037247" y="0">]</tspan>
</text>
</g>
</g>
</svg></span></td></tr><tr><td class="thead-hr" colspan="5"><hr/></td></tr><tr><td align="left"> Nodes</td><td align="center"> 657</td><td align="center"> 241</td><td align="center"> 177</td><td align="center"> 65</td></tr><tr class="table-tr"><td colspan="5"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

Visited nodes in tree search with different fixed branches in 16-QAM modulation 4 × 4 MIMO system.

Journal of Electrical and Computer Engineering

tab3

Table 3

Table 3: A Power-Efficient Soft-Output Detector for Spatial-Multiplexing MIMO Communications 