WEBVTT 00:00:00.000 --> 00:00:04.640 Obviously, your phone gets its signal from a cell tower, but where do those towers get 00:00:04.640 --> 00:00:09.520 their signals from? Do they pass data between each other, or is there one tower at some 00:00:09.520 --> 00:00:14.320 headquarters somewhere acting as a source of all the content? Most cell towers are basically 00:00:14.320 --> 00:00:19.760 big wireless antennas connected to a router at the base via cables, which are plugged into the 00:00:19.760 --> 00:00:24.800 back hall of the carrier's network so you can both make voice calls and connect to the internet. 00:00:24.800 --> 00:00:29.440 If you think about it, the setup is kind of like a really big version of a Wi-Fi access point 00:00:29.440 --> 00:00:35.280 connected to a normal router or modem. But this doesn't mean that towers never talk to each other. 00:00:35.280 --> 00:00:39.520 If you look up the next time you're riding past one, you might see an antenna glob down to the 00:00:39.520 --> 00:00:44.960 side of the tower that looks like a big bowl, dish, or drum. These are special microwave antennas 00:00:44.960 --> 00:00:50.400 responsible for wireless back hall, and they're usually pointed directly at another tower in 00:00:50.400 --> 00:00:54.960 case there's a problem with the wired network underground. And some towers even use microwave 00:00:54.960 --> 00:01:00.800 antennas exclusively to get your phone traffic where it needs to go, especially if laying cables 00:01:00.800 --> 00:01:06.480 in an area is too expensive or physically unfeasible. But the back hall just connects towers to your 00:01:06.480 --> 00:01:12.880 carrier. It doesn't connect to your phone. So where are the antennas that actually provide your 00:01:12.880 --> 00:01:18.560 phone with a signal then? Okay, steer to cell tower for a little longer, and you'll see skinnier, 00:01:18.560 --> 00:01:24.880 vertically oriented antennas. These are what give your phone that sweet 4G or 5G. 00:01:24.880 --> 00:01:29.440 Unlike the typical wireless router antenna, which blasts a signal out 360 degrees, 00:01:30.000 --> 00:01:35.440 cell antennas are usually more directional. They focus the signal one way. Although this might 00:01:35.440 --> 00:01:39.760 sound counterintuitive, as you obviously want to have a signal extend out in all directions from 00:01:39.760 --> 00:01:45.760 around the tower, it actually makes sense. Having multiple directional antennas provides a stronger 00:01:45.760 --> 00:01:50.720 signal than just one central omnidirectional antenna. A typical setup is to have them arranged 00:01:50.720 --> 00:01:56.160 in a triangle, with each covering 120 degrees instead of 360. On the side of each triangle, 00:01:56.160 --> 00:02:00.720 you might have something like three directional antennas covering 40 degrees of space each. 00:02:00.720 --> 00:02:06.080 You might also see multiple layers of antennas stacked on a tower. But this is usually not 00:02:06.080 --> 00:02:12.000 for signal strength. Instead, it's common for different wireless carriers to share a tower. 00:02:12.000 --> 00:02:16.320 With whoever gets there first, typically taking the very top level, kind of like siblings fighting 00:02:16.320 --> 00:02:20.480 over the bunk bed. But the real ones know that the bottom bunk is actually the best. 00:02:20.480 --> 00:02:24.720 And although it can be hard to tell from the ground, these antennas are often tilted slightly 00:02:24.720 --> 00:02:29.280 downward, and transmitting at reduced power to reduce interference with neighboring towers. 00:02:29.920 --> 00:02:34.560 Ideally, this is calibrated so that the signal extends to just the end of where the next tower 00:02:34.560 --> 00:02:40.000 picks up so that you won't run into any dead zones. On that note, exactly how far does a cell 00:02:40.080 --> 00:02:44.880 signal reach? Well, if we're talking about a 4G tower that has some open space around it, 00:02:44.880 --> 00:02:50.880 those can send a signal to about 40 miles or so. Midband 5G, though, has a significantly 00:02:50.880 --> 00:02:56.000 shorter range of only around 6 miles at best. So instead of very tall towers that try to 00:02:56.000 --> 00:03:01.040 blast signals as far as possible, the faster iterations of 5G tend to use shorter towers 00:03:01.040 --> 00:03:06.480 that are relatively close together, sometimes well under a mile apart. Some cell deployments 00:03:06.480 --> 00:03:10.640 even place antennas on the sides of buildings, obviating the need for a tower at all. 00:03:11.200 --> 00:03:15.760 And this might become more common as 5G continues to roll out in dense urban areas. 00:03:15.760 --> 00:03:22.080 But it is a shame that city dwellers might never experience the beauty of a fake cell tower cactus. 00:03:22.080 --> 00:03:25.680 Thanks for watching guys, like, dislike, maybe check out some of our other videos, 00:03:25.680 --> 00:03:29.200 comment with video suggestions down below, and don't forget to subscribe and follow.