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by mostlyskeptical 3272 days ago
Real cell towers may use more power than unlicensed is allowed to in some cases, but not significantly much and definitely not hundreds of times. I worked at Clearwire (Clear wimax) and even on the spectrum we owned we generally used less than 1W of power per sector. Very small ones would only use a couple of hundred mW and our longest range sites in rural Texas were either 2W or 5W (memory is fuzzy).

To be fair, we used more sites closer together instead of a few larger ones, but the point stands. Cell sites biggest advantage is elevation and line of site, not massive transmit power.
1 comments
flashdance 3271 days ago
I work at Ericsson (one of the largest radio companies in the world) and we have towers that crank out 80w for 4g/5g. Mind you, I'm a software guy, not a hardware guy.

Elevation and line of sight are important but power is too!

Ctrl-f "watts" on this page to see what I'm talking about:

https://www.ericsson.com/en/networks/offerings/connecting-th...

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Johnythree 3271 days ago
You are confusing peak power with average power. The law of reciprocity says that nothing is to be gained if the base transmitter is more powerful than the mobile TX.

However because the base has multiple (hundreds) of low-power transmitters, it must cater for a very large instantaneous peak power when they momentarily add up.

And more importantly, excess Transmit power reduces the re-use ability of that frequency in nearby cells.

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flashdance 3270 days ago
> The law of reciprocity says that nothing is to be gained if the base transmitter is more powerful than the mobile TX.

Late response, but that assumes that the mobile RX is as good as the tower's RX, and I can assure you that's not the case.

The gear up on a tower has a way better low noise amplifier than a mobile phone, so it's able to "hear" the phone at a greater distance than you'd expect. That's why it's a-okay to have a base transmitter with a quite a bit more power than a mobile TX.

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Dylan16807 3271 days ago
> The law of reciprocity

The what? The only thing I can find about reciprocity is that antennas have the same characteristics in either direction. That doesn't mean your noise levels are the same, and you very often have different bandwidth requirements in each direction.

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