Radio waves bouncing off each other is a simple and straightforward consequence of applying the Poynting vector and the Poynting-Heavisde theory of electromagnetic energy flow to superpositions of electromagnetic waves. They "bounce" in the sense that a forward propagating wave exchanges energy with a reverse propagating wave. The waves pass through each other, but the energy recoils elastically or "bounces." See <a href="http://arxiv.org/abs/1407.1800" rel="nofollow">http://arxiv.org/abs/1407.1800</a> for more technical details.