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Why satellite frequency can't penetrate walls and radio can?


Lucis
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Usually am radio wave are going through matter more easily. it may be use: https://www.quora.com/Why-cant-radio-waves-transmit-through-water, Im looking for more...

The answer requires that you understand electron orbitals and the amount of energy that is required to kick an electron from a discrete lower orbital to a discrete higher one. When a photon (light, radio, x-ray etc) passes through an atom, an electron in the atom can absorb it if the photon contains enough energy to kick the electron to a higher orbital. If the photon doesn't contain enough energy to be absorbed by the electron, then it simply passes through.

Due to the discrete nature of electron orbitals, electrons will only absorb photons of particular wavelengths (energies)

I took it from the web, its not from me

Edited by MaximThibodeau
i didnt express myself correctly, sorry
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1 hour ago, zapatos said:

I lose the AM signal on my radio driving my car under an overpass.

You loose FM under a tunnel or in a garage as well.

Edited by koti
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14 hours ago, koti said:

You loose FM under a tunnel or in a garage as well.

You can, but FM goes into tunnels/garages better than AM, because the wavelength is about 100 times shorter. AM is around 1 MHz, so the wavelength is ~300m, and a tunnel looks like a waveguide below cutoff. FM is around 100 MHz, so the wavelength is ~3m. If the tunnel can "see" the antenna, then you should still get signal. If it's getting away from that orientation, then the problem is the attenuation of the materials.

 

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23 hours ago, Fuzzwood said:

I am getting a gps signal on my phone (while inside my room) just fine. So what bandwidth are you referring to?

I'm referring to the TV satellite , frequency between 11 GHZ & 13 GHZ

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10 minutes ago, Lucis said:

I'm referring to the TV satellite , frequency between 11 GHZ & 13 GHZ

You've gotten into a frequency range where you are interacting with materials.  Lots of rotational state features.  

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I receive my television on 12GHz.   Think of a distant light bulb that has to illuminate an immense area.  Not a narrow beam directed only to your reception antenna.

The transmitted power from the satellite is spread so thinly to cover a huge area, that the reception signal level is faint at your location after propagating thousands of kilometres. Additionally,  if you place  obstacles in the signal path weakens the signal even more to the point of being less than the receiver sensitivity.  Your 'radio' stations may be much nearby yielding a stronger signal.  Some electromagnetic frequencies are also subject to attenuate, bounce, fade more or less than others.

A random  chosen footprint for a television transmitting satellite over Ecuador, its antenna aiming north America :

image.png.bb023e2c733ea40dcba5f9cfbdb8ba5c.png

(Nimiq 5 at 73W; taken from satbeams.com)

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