Pinterest Stumbleupon Whatsapp

radiotowerIn my role supporting SCADA units in the field, I’ve often been asked how does Wireless Internet work. I usually answer with the question, “Which kind of wireless Internet?” Some people say that WiFi is wireless Internet, some think of radio-based Internet access as wireless, some even think of satellite Internet access as wireless. Then there is cellular based Internet access as well. At that point, you guessed it, glazed over eyes and wandering away. Please don’t do that – I’ll get to the point soon.

Canopy 440 ReceiverReal wireless Internet access is most accurately described as the kind that is based on radio frequencies. You might see homes with the little white rectangular box mounted near their eaves trough. Those are folks with Wireless Internet Access.

Let’s work this from the Wireless Internet Service Provider (WISP) to your computer.

From your ISP there will either be cabling or a radio transmitter that will relay signals to a tower. It may go through several towers before it gets to your home, or you might be close enough that you catch it off the first one.

See, the challenge with wireless Internet service is that it should be line-of-sight. That means that if you were to put your head in the middle of the receiver and look straight ahead, you have to be able to see the tower. (I do NOT recommend doing this since those signals could be less-than-healthy for you.)

Once the signal makes it to your nearest tower, it then travels directly to your receiver.  From your receiver, it will go over ordinary networking cable (RJ-45) to your modulator/demodulator (you know it as a modem). When it is modulating, it is turning your outgoing information into something that the wireless network understands. When it is demodulating, it is turning the signal into something your computer will understand. Clear as mud? I thought so. Here’s a picture.



As I said before, this is all done with radio frequencies. Do you have a cordless telephone? It will probably have numbers on it that read something like 900 MHz, 2.4 GHz, 5.2 GHz or 5.7 GHz.? These are the radio frequencies in which your cordless phone operates. Well, so does wireless Internet!

The WISP’s use these frequencies because they don’t require a license to do so. Licenses cost money and come with severe restrictions, so why wouldn’t you use public frequencies? Ah hah! I heard someone say ‘security’! You are correct. Yet communications over these frequencies are acceptably secure. That’s because encryption is added to the signal. They take something that someone might possible be able to unravel, put it through encryption and, voila, secure Internet signal. Well, as secure as it can be anyway. DES encryption is commonly used.

Now, I hear someone asking why there are different frequencies. Think of them like highways – too many cars on it and everything comes to a standstill. So we use more than one highway.

Something else to consider with wireless Internet is that the frequencies also offer different attributes. Have you noticed that you can’t take your new 5.2 GHz cordless phone three doors down and still be able to talk on it? Yet when you are in your house the clarity of voices on it beat your old 900Mhz phone easily.

It’s similar with wireless Internet. Looking at Motorola’s Canopy receivers, you’ll notice that the 900 Mhz receiver has an effective range of up to 40 miles! Then the 2.4GHz receiver is limited to about 5 miles. That’s a huge difference! Go all the way up to the 5.7 Ghz receiver and we’re down to a measly 2 miles. However, the 900 Mhz receiver is more likely to have its signal interfered with by other signals out there. So, your choice, range or quality of signal? Choose wisely.

Are you currently using stationary wireless a.k.a broadband wireless? Like it? Hate it? Does this article help you to understand better what is going on with it? Let us know, down below!

Leave a Reply

Your email address will not be published. Required fields are marked *