For example, when using your phone in areas of low service and the internet is slow or call audio quality is poor, what is happening to the radio / microwaves in transmission to your device?
In: Planetary Science
I’m not sure scattering is the right word for poor cellphone coverage. Scattering is when light passes through something with a clear input direction, and then leaves in a bunch of random output direction. Sunlight comes to earth from one direction, and the atmosphere scatters it. It scatters the blue more than the red, so the sky glows blue in every direction, not just from the sun.
Cellphone reception being poor is mostly due to two things: range and obstructed line of sight.
Cellphone and towers don’t beam lasers directly at each other. Towers point in a lose direction, that’s why you see multiple antennas on all side of a cellphone tower. They also all usually point slightly down. Phones are omnidirecitonal, that is they send the radio waves in all directions.
Phones lose signal at range because it weakens over distance. If you want to describe it as photons. Imagine the phone send out 10 trillion photons in a random ball. Stand 10m away, a lot will hit you. Stand 10km away, and a lot less will hit you. The photons didn’t vanish, they just missed you. That’s why the tower has trouble talking to a phone far away. If you view it as waves, it’s no different than having a conversation across a field. Waves go out in a sphere, sp the energy gets weaker over distance. 10 Watts of power over a 1 m sphere is a lot more power density than 10 W over a 10km sphere. The Watts didn’t vanish. They spread out. Watts, photons. Take your pick, same idea.
The second, line of sight, is easy. Ypur phone and the tower basically need to see each other to work. By see, I mean see in radio waves. This is easier than visible light, drywall is a clear window to radio waves. There are a lot of transparent windows for radio waves. A mountain is still going to block the signal. A think amount of concrete will block the signal. A thin sheet of metal will block the signal. A metal box would have terrible reception, even next to a tower.
Interference too, but for cell bands, that’s fairly regulated. Wifi is another story. Lose 2.4 GHz wifi when you microwave is on? Not a coincidence. Poor bluetooth headphone sound quality in say a busy area of a city is another common interference issue with 2.4 GHz band. Interference is pretty easy to explain. Try having a conversation in a room full of noise and other conversations versus a quiet room. That’s just sound interference, same thing. Not analogous, literally the same thing. If you phone is having trouble talking to your wifi router, it’s because the microwave oven is screaming nonsense in the background.
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