this post was submitted on 06 Sep 2024
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Well, air-concrete-air is 2 media but 3 transitions. You can re-use the model for the transition which makes the math easier, but you still have to re-do all the math with different numbers, some of which you have to determine by analyzing the transformation the signal channel underwent through the transitions.
I don't think it would be an order of magnitude more power for EM trying to go through a transition between air and concrete, it's not like the wave is actually moving the matter so much as its bouncing into it sometimes, and the change in propagation velocity and group delay coupled with frequency rolloff in the transition, but it adds a ton of noise, mostly as the group delay gives you effective multipath, and especially modern modulation relies on heavily phase measurement (PSK and QAM) which can make everything all really icky when the phase interference is that small, we designed our modulation for large phase interference like multipath reflections, etc, the assumption that going between media would cause the reflected/refracted component to heavily rolloff, which might not be the case here.