If it works similar to my sight survey card, it'd be close to invisible. There could very easily be a set of common frequencies and phase angles that it would just pan through as it goes with a very low powered and essentially empty carrier wave. When something on the same freq and phase were broadcasting into the same space, constructive interference would create slight crosstalk and the TI would be aware of the presence of the node (and very likely the other way around as well, if TI works in the wireless mesh topology I'm picturing from that brief description).
The beauty of a set up like that is, if your carrier signal is on one phase, other phases of the same waveform can be used to carry the meaningful information, which makes the (fractal) antennae much less costly and simple.