Cactus TurboNet Newsletter April 2008               

   The Many Faces of Wireless Internet

When someone says they have “wireless Internet”, what do they mean?

1.  It might mean that within their home, their computer connects to a wireless router.  The signal might reach their home over the phone line (ADSL), cable, wireless, fiber-optic, or even dial-up, but it’s wireless within the home.  (We sell wireless routers in many different flavors.)

2.  It might mean that the signal gets to their home through the air, without wires.  Normally there’s a radio mounted on the outside of the building to receive the signal.  Within the home, they might also have a wireless router, or a hub, or connect directly to the radio with a cable.  (We provide wireless connections to homes – phone us to see if you’re in range.)

3.  Or they might skip a step, and a radio (wireless card) in their computer might connect to an access point outside the home - on their apartment building or nearby.  (We have a few hotspots in Moscow, Pullman and Garfield.)

4.  It might mean they use their cell phone for Internet.

   With all of the above, the quality of the wireless signal (and your Internet speed and reliability) depend on four things.

1.  The quality of your radio.  You can roughly judge quality by price, but as with all things electronic, you can pay too much for junk, or you can get a bargain.  Some very good radios cost over $500, and can send reliable signals for miles.  MIMO radios and other radios with multiple antennas have special firmware which can take advantage of signal reflections from buildings and large metal objects, using them instead of considering them to be noise.

2.  The distance between your radio and its access point.  Most radios you find in a notebook computer are good for a couple of blocks if there’s just air between the radio and its access point.  Since you don’t normally use a notebook outside, think of the practical distance as about three walls.

3.  What’s in between.  With an outdoor radio attached to your home, you might have just air, trees, buildings, or a hill in between your radio and your access point.  The more water that’s in the air, the less reliable the signal.  If there are trees, the denser the foliage, and the wetter it is, the worse the signal.  With buildings, the more steel or concrete in them, the worse the signal.  And any hill cuts you off entirely.

4.  The background noise.  In the 2.4 GHz spectrum, background noise comes from wireless routers, notebook computers, microwave ovens, garage door openers, X-box consoles – the list seems endless.  That’s why 2.4 in an urban environment is only good for short range.  In the 5.8 GHz spectrum there is much less noise, so interference usually comes from other 5.8 GHz access points on the same frequency.