Eli5:Why is it that cell phones , with their tiny antenaes are able to download files at LTE speeds inside concrete buildings from cell towers kilometers away yet getting wifi to work behind a corner is an exercise in frustration?

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Eli5:Why is it that cell phones , with their tiny antenaes are able to download files at LTE speeds inside concrete buildings from cell towers kilometers away yet getting wifi to work behind a corner is an exercise in frustration?

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Anonymous 0 Comments

Imagine a wireless signal is a string. Your cell signal and WiFi are the same length. Data is beads being sent along the string.

A cell signal is a lower frequency, so the string is put on the ground fairly straight with less “waves”, which means the beads can pass by your device one at a time, but they car go further along the string.

A WiFi signal is high frequency, so the string has a lot of “waves”, which means a lot of beads are able to pass by your device at the same time, but they can’t go as far because of all the corners they have to go around.

You also have to remember, LTE speeds are fast, but WiFi is *much* faster, with the slow speeds because of the internet connection, not the wifi

Anonymous 0 Comments

My favorite elif posts are the ones where the top 5 comments all say the person who explained it before them is an idiot and needs to take it upon themselves to rehash what everyone has said but with slightly different wording. Relax, we’re *all* special.

Anonymous 0 Comments

For the same reason you might struggle to hear a whisper from the other room, but you have no trouble hearing the nuclear attack horn miles away.

Anonymous 0 Comments

You fucking serious? You don’t know how cell phones and wi fi works?. Wifi is a limited signal coming from a small router. Not very powerful. A cell phone works off a giant tower.

How do you not know how the thing you carry in your pocket everyday works?

Anonymous 0 Comments

I wasn’t satisfied with the other answers. This is my best Eli5. *Source: used to work at AT&T.*

– Your phone usually hums a low tone (under 1ghz) which can penetrate most walls with ease and reach a cell tower that’s listening miles away. Your phone has to compete with all of the other phones and cell towers talking within miles of you, but luckily every phone and tower abides by strict rules and has a ton of space to adjust their pitch so they know who is talking.
– On the other hand, with Wi-Fi and Bluetooth, your phone has to use a shrill voice which barely reaches the other room to talk to your router (2.4ghz or 5ghz). As it happens, everything else in your house is forced to talk at only those 2 high pitches and it’s really hard for everyone to hear each other. Kind of like a school cafeteria at lunchtime. Even your microwave, when running, has to use this same shrill pitch.

T-Mobile service used to really suck in comparison to Verizon and AT&T because it was only licensed to talk in a relatively high pitched voice. Luckily, the government let them start humming that low, penetrating frequency like the other carriers, in exchange for a bag of money, of course.

Anonymous 0 Comments

Cell towers are absolutely BLASTING their signal–they have permission from the FCC do to this, and it works. WiFi is meant to be a personal or smaller-scale thing, and works at far lower power levels. As a result, the signals are easier to block.

If you want a fun read, google “cantenna” for a cool way to boost your signal.

Anonymous 0 Comments

There are many good explanations of different factors at play here (frequencies, number of routers/cell towers, signal power, etc), but I’d like to clear up a couple of assumptions you made here. In urban areas, cell towers are generally not kilometers away. And when cell towers *are* kilometers away, you won’t get your typical LTE speeds, it will be slower. There is always a tradeoff between connection speed and signal range – the higher the signal range, the lower the speed, and vice-versa. Of course, every new generation generally increases the speed for a certain range, but that truth still stays. I mean, think about it, if you didn’t have that tradeoff, we would all (probably) be using satellite internet.

Also, Concrete buildings don’t necessarily let cell signals through. What most concrete buildings have, though, are windows – and they do let signals through. But if you’re in a concrete building without any windows, and there’s nothing to bring the cell signal there, chances are, you won’t get any reception.

Anonymous 0 Comments

Cell phone towers are large massive towers that are built to provide cellular signal to large areas of the city. They have miles in range and use a lot of power.

Your wifi router plugs into the wall and is made to NOT be so powerful as to extend into other buildings and cause interference with other wifi routers. Their range is 200-300 feet when there is no walls between the router and the device using it.

So by design they have different ranges because by design they serve different purposes.

Anonymous 0 Comments

Most hotspots have a damn weak broadcast power! So the further you are, the nore likely your data transfer speeds are equaling those of the 1990’s.

Anonymous 0 Comments

The answer is they don’t. Commercial concrete buildings usually have multiple “micro cell” sites installed throughout the building to support cell phone data and voice communication. If this wasn’t done the density of cellphones would quickly overwhelm most cell phone towers in cities.
Cell phone towers have limits to the number of simultaneous connections. 5G requires even shorter distances than LTE, so there has been a major increase in the number of cell towers from previous needs. Here’s some good apps and websites to see just how many are around you. You won’t believe how many are located at Sport Stadiums
https://www.waveform.com/blogs/main/cell-tower-mapping