That's true--as far as it goes. There is also GSM-1800, GSM-1900 and PCS, at 1.8GHz, 1.9GHz and 1.9GHz, respectively.
"Can" being the operative word, here. We're talking near-microwave to microwave frequencies. They don't work like "garden variety" RF works. It can
happen, but the effect is completely arbitrary, because the behaviour of the "conductors" is completely arbitrary at those frequencies.
Depends. In free space there's the distance squared rule. But we're not in free space, we're in the atmosphere, which is full of water and dust and stuff. Again: We're talking near-microwave and microwave frequencies. The attenuation is much greater than at lower frequencies. And that's just line-of-sight: I.e.: Nothing in the way. At these frequencies, LOS is all
you have. Fixed-station microwave communications towers generally aren't placed more than 30 miles apart, and they're dealing with a good deal more power, and significantly better receivers than your average cell-to-handheld link. (Commonly, max. LOS for cellular and PCS is 10 miles, give or take, in open country or across the water.)
That's not quite accurate, either. It's the sensitivity and
the signal-to-noise ratio
. Which brings us to...
Mostly it's the receivers in the towers. There's no end of things you can do to increase sensitivity, improve S/N and reject interference when you aren't space-constrained
(Ex-microwave communications systems and SatCom guy, in case you were wondering.)
Look Jim.. I'm not going to argue with you about correcting my remarks.
You're a sailor, I'm not going to tell you how to set a sail, or when to reef it.
Don't tell me what you think I don't know about radios.
I've stated everything accurately. My background is over 40 years in radio - and NOT Ham radio. Professional, military radio systems. I've designed a lot of antennas. I do know my radio and antenna theory. I've been keeping it simple.
Certainly there are plenty of cell phones and types - but the VAST Majority of them are in the 800-900 Mhz band. Period. The phones that most people buy, and use are.
And it IS the front end, sensitivity that is taken into account, which includes the s/n ratio when you look at it from the end user's perspective. I'm trying specifically to not be too technical in detail because honestly, no one will read it if it is technical. If they have an idea of what to try, they can try it for themselves.
So - "Free space versus Atmosphere"... is utter BS.
It has nothing to do with atmosphere. They talk of "Free Space" as not being around objects with ground reference points and you know that as well as I do.
By the way, I'm not "ex" anything. I am still and always will be a radioman first.
Cellular telephones, regardless of the type are operating in the UHF and higher frequency bands. They are LOS ONLY. Period. If you can't see the bloody tower with a straight-line radio signal you ain't gonna hit it. Period. Reflective signals notwithstanding, you have to have enough signal for the tower to receive it.
YOU and I have no control over those towers or their antennas and normal users don't either. The ONLY thing they can do is get into a good signal. Their radios are much less powerful than the towers and while a phone might show a good receive signal, you might NOT make it to the tower.
So you can see we agree on a couple of things. But, don't make the mistake of going too technical here on radios. Most people, including the OP, don't know enough to make heads or tails of it. He even said "it's Magic" to him.
Keep is simple. You might find yourself in the same predicament when it comes to radio theory if you don't....