Hi Jorge,
The short answer is no if they are all using the same radio (802.11g) for example. Because all the devices are sharing in the medium. So even if you added another SSID these devices are still on the same channel / radio thus sharing the same medium.
However, if you are curious, your ap does support 5 ghz (802.11a). You could broadcast the same ssid on the 5 ghz side, and attach 10 of your devices to the 802.11a side. This is of course if your devices support 802.11a.
Unless you are pulling heavy video and data, in most cases 20 clients are fine on a single access point.
I hope this helps.
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
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