Since the short-range devices seem to be regular battery-powered electronics (they've rarely been plugged in), Tony just installs a few larger devices powered by gigawatt arc reactor/repulsor 'battery' (or whatever we're calling it these days) generators on the top of the largest buildings in the city. Either that, or since he's all about networking these days, does it like a wifi setup for the city with jammers and repeaters every city block or so.
And for the specific type of emanation we're talking about here, I'd expect the jammers to deal with obstructions about as well as what they're jamming... and telepathy has never really been presented as blocked by walls or being in a subbasement in the MU as far as I can recall.