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The Future of Wireless Connectivity
Unimonomous writes "CoolTechZone.com analyzes the future of wireless connectivity with WiMax standard. "WiMax is an upgrade from Wi-Fi and offers brilliant advantages over its predecessor. The obvious one being extended range (up to 15 miles), which means that establishing a few towers would pretty much make the entire city connected. Now this probably won't matter to those of us with 24/7 connectivity, but people living in rural and undeveloped areas would surely benefit from it." Update looks like the site buckled. Sorry.
Looks like CoolTechZone is down...second story today that the referenced article was unavailable...
Anyway, just so we have something to talk about...here's some info on WiMAX:
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~ |rip/\/\aster /\/\onkey
Drill baby drill - on Mars
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but people living in rural and undeveloped areas would surely benefit from it
Unless you are talking about automating your farm equipment with wifi, I doubt many rural areas will see this until far into the future.
Who is going to pay to set up a tower to give 20 people internet? The reason wimax is so attractive in cities is the user density. I suppose the point is that it is cheaper than laying new land lines in rural areas (where broadband capable lines may be absent)?
It doesn't seem likely to happen any time soon, though. And there is still the matter of wiring the towers. Unless you wanted them to route signals wirelessly... I wouldn't want to risk my data travelling hundreds of miles over air. Fifteen is bad enough.
Nothing worse than exposing your php/mysql site with an error message. Hello.... security?
(let's hope the website is fixed soon)
Wimax doesn't require line of sight.
http://en.wikipedia.org/wiki/Wimax
In fact, aside from IR, I don't recall any standard wireless communication that was only limited to line of sight. Obviously, density and EM radiation attenuation properties of the objects between sending and receiving antenna will affect the range and signal strength. But that doesn't mean it won't go through walls.
There are two types of people in the world: Those who crave closure
Here's a nice link for you...you'll need to have GreaseMonkey installed for it. Won't do you much good in this particular instance, but might help in the future.
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~ |rip/\/\aster /\/\onkey
It should be noted that these claims, especially that such distances can be achieved without line of sight, represent, at best, a theoretical maximum under ideal circumstances
Line of sight is ALWAYS going to be required in that frequency spectrum, unless you are very close or at very high power levels.
..don't panic
WiFi offers maybe 110Mbps in a 700m radius. WiMax offers maybe 650Mbps in 24000m radius. That's 71bps:m for WiFi vs. 0.36bps:m for WiMax . WiFi is 200x as dense as WiMax. Rural areas have much larger areas which don't account for bandwidth usage, with big users every few miles. While urban areas have much more even distribution of consumption - even stacking 3-4 layers per meter, sometimes 20-50+ layers (like urban centers like Manhattan). Real consumption shows that WiMax is better for rural areas, or long backhauls (attenuated into beams that can carry the network maybe hundreds of miles across gaps like open water). Even in rural areas, WiFi is better for the hotspots, like actual buildings or vehicles. While in urban areas, even public places like streets are very dense, with 655Mbps shared by hundreds of people every block.
So WiFi isn't exactly an "upgrade" to WiFi. It's a complementary technology. Even throttling down the power to cover only a few blocks with each WiMax AP to use its higher bandwidth is only useful as a connection "umbrella" to interconnect denser WiFi hotspots in buildings and cars. Which is also appropriate, because users in public places are usually mobile or casual, without the bandwidth demands of a stationary user. WiMax marketers are selling it as an upgrade to WiFi because WiFi is such a popular brand name, and WiMax has to sell to anyone who will buy. But we should get excited only about the WiMax features that are actually better than WiFi in the scenarios where WiFi is now the round peg in the square hole. Otherwise we'll be sorely disappointed when inappropriate WiMax applications underperform even WiFi, and we'll be stuck with the wrong solution - and the marketdroids will be stuck with our money, without which we can't buy what we actually want.
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make install -not war
Wimax doesn't require line of sight.
No, but you must be damn close to line of sight (you must be NLOS - near line of sight). And you need something for signals to reflect off of. WiMax is able to handle multipathing and multipath distortion of signals.
But that doesn't mean it won't go through walls.
When we're talking about RF frequencies above 1 GHz, if the relevant signals goes right through a wall from transmitter to receiver, you have line of sight for it. Line of sight means the signal is going from transmitter to receiver directly without significant reflection, attenuation, or refraction. If the signal does not arrive directly, you do not have line of sight. If the signal arrives mainly via reflection or refraction (possibly by more than one path, 'multipathing') you have near line of sight (NLOS).
Examples:
If you have two antennas on opposite sides of a wall, and the signals go through, you have (direct) line of sight.
If it doesn't go through the walls, you do not have line of sight.
If you do not have line of sight but the signal goes out the door of one room, bounces down the hall and into the door of the other room and to the other antenna, you have near line of sight.
If you have an 2.4 GHz transmitter on one side of a magic optically transparent glass wall that blocks 2.4 GHz, and a receiver on the other side, you do not have line of sight for 2.4 GHz. You do have line of sight for the visible spectrum, however.
"Alcohol, Tobacco, Firearms, and Explosives" should be a convenience store, not a government agency.