Dealing with wireless interference from cellphones

[Phalanx]

The question that needs to be asked is at what frequency band where you operating your DLINK and Driver Station at?

1) If you are using the 2.4ghz frequency, then yes, it's highly likely there was lots of interference from all the cells phones in the room, also broadcasting in the 2.4ghz range.

2) Does the school also have wireless? The schools wireless AP's could also be broadcasting in the 2.4ghz band. Again that creates even more "noise".

So all the cell phones and schools network are creating so much wireless noise your D-Link and Driver Station can't maintain a clean, reliable signal.

If your driver station and dlink are using the 5ghz frequency then you shouldn't have been impacted to that extent.
IIRC there are not that many cells phones that operate in the 5ghz band.

Lastly, having a 25 or 50 foot Ethernet cable available to be tethered instead of wireless can be helpful for such demos.