how do radio signals (4G, WiFi etc.) manage to retain their information after passing through trees, buildings and other obstacles? And how are they not mixed up, intertwined?
In: Technology
They are, the key is there are error correction and detection algorithms that work to counter the problem. In bad environments they don’t always work.
Also, many newer devices actually utilize the attenuation and reflections to improve signal quality. Take a look into [MIMO](https://en.wikipedia.org/wiki/MIMO) technology. They do what is called [beamforming](https://en.wikipedia.org/wiki/Beamforming) where they vary the signal being output on multiple antennae to create hot spots in the signal at the receiving antenna(e) to improve reception. When multiple devices are connected it will actually change the beam forming per device moment to moment depending on the destination. It’s really cool stuff.
Edits: Links, typos.
Edit 2: Figured I could expand as well. When you’re dealing with reflections or other signals that could potentially interfere, they are usually a bit weaker than the main signal. This means that a receiver can filter them out by simply ignoring signals that are weaker than a certain level. This is called the noise floor of the radio. Think of it like being in a room full of people talking and ignoring all the background conversations because they’re harder to hear and focusing on your current one.
Attenuation of the main signal works similarly. As long as the signal isn’t attenuated below the noise floor, it will work. If the operating environment for the radios is bad enough, it may be impossible to get a strong enough signal to overcome the noise floor, and then nothing works.
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