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Psychologists explain that people primarily have a need for food, followed by safety, and then a sense of belonging. In the last twenty years, this seems to have changed to first WiFi, then food and safety, and that sense of belonging will come naturally. In the past, conversations began with all sorts of pleasantries, but nowadays your WiFi password is the first thing asked for.
Have you ever wondered how this marvel of modern civilization works? I'll try to lay it out simply.
Perhaps we would understand it better if we knew what the word WiFi means. Wireless Fibercable perhaps? No. Officially, it would be called something like IEEE 802.11 Direct Sequence, but of course, no one would remember that. Then a clever marketeer came up with the catchy term WiFi, which actually doesn't mean anything but everyone easily adopts it. Marketeers are good at that.
Some people seem to think that WiFi is the same as the Internet. However, WWW stands for World-Wide Web, not Wonderful WiFi World. The Internet is a global network of computers that communicate with each other, forming one large system. WiFi is one of the technologies that allows them to communicate. This can also be done with LAN cables, fiber optics, phone lines, etcetera. WiFi is essentially digital radio, like DAB for data, a kind of wireless LAN cable.
WiFi operates on radio frequencies similar to those used by your mobile phone. The use of such high frequencies means that the transmitter and receiver must be able to "see" each other. WiFi cannot "see" over the horizon, just like DAB or your mobile phone. That is why there are tall masts in IJsselstein or Lopik in the Netherlands - although those are not for WiFi - or all those antennas on high buildings.
The WiFi transmission power is never very high, otherwise you would get interference between routers, or your robot vacuum cleaner might start behaving in an unsettling manner. In the Netherlands, one-tenth of a Watt is the standard, which is about the power your headphone amplifier provides. With more power, you could indeed browse in the back of the garden, but the connection would become unreliable because your neighbour would want that too. Besides, WiFi signals cannot travel further than the line of sight of the router, remember?
Several building materials weaken radio waves, such as reinforced concrete, plaster, or glass. You notice this for example in a large shopping center – mobile Internet becomes so weak that you can't consult your shopping list on your phone. Fortunately, shopkeepers install WiFi hotspots. At home, you’ll notice that on the attic your WiFi becomes very weak. Then a WiFi booster helps, as long as you place it where the signal is still decent – a booster can't create something out of nothing, of course.
Why do we actually have both WiFi and Bluetooth – both are wireless and work at almost the same frequencies, right? The difference lies in the application. WiFi is really intended for efficient wireless Internet traffic, while Bluetooth is meant for short-distance generic communication between Bluetooth devices. These two uses cannot be captured in one single solution, so we have two systems.
Now I have to fiddle with the WiFi antennas on my router to get this piece uploaded to my server so you can read it.
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© 2002-2025 J.M. van der Veer (jmvdveer@xs4all.nl)
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