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Possible Big Boost in WiFi Range
goger writes "An article in the New York Times this morning (insert obligatory note about free registration here, and don't forget the yada's) talks about a startup company in CA that says it will announce WiFi antenna technology today that can give a 2000 ft. range indoors (and up to 4 mi. outdoors). This would be awesome if they really deliver, of course (and if it doesn't require me to set up something the size of a rooftop TV antenna next to my laptop in the coffee shop...)."
Pringles will now be selling just the cans - no chips to dispose of first.
The outdoor range could replace my current ISP.
This could be a bad thing. If all the people in the suburbs drop their ISP's and leach on the fewer open ports they can now reach, the owners may clamp down on free access to get their bandwidth back. When it was short range, there were more points as more people would pay for bandwidth and would share with the few that could reach them. Now many users will consider dropping paid access and leaching the open ports. This may kill them just as it killed free dial-up ISP's. Sharing works only if enough users provide bandwidth to the system to prevent overloading access points. It does not work if most users drop their current ISP to leech off the generous few. The generous few will be hit with excess bandwidth demands and will have to re-think their generosity. Most ISP's already prohibit sharing the bandwidth. High usage may entice cable companies and DSL providers to start wardriving and shutting of offenders sharing bandwidth via wireless.
The truth shall set you free!
The tech is a phased array antenna, there was a good article about using it with 802.11 (notice there is no b) in the IEEE spectrum a while ago.
Consider it a sort of software antenna, you have a series of antenna that you can bias towards a particular direction. You then listen for incoming signals and use a processor to calculate environmental multipath (RF signals bouncing off buildings, etc.) and then fire off your signal so that the main signal and multipath reflections arrive at the reciever at the same time. Instant gain.
I'm skeptical on the reported max range but they should get a good amount. If you're sitting in the middle of a parabolic dish and so is your target, sure I expect that kind of increase in range, but in the real world...
Can you ping me now? Good.
B.
Your statements are true for a passive antenna design. There's only so much effeciency you can squeeze out of a chunk of metal.
However, this antena is not a passive antenna. It's a fully active antenna, specifically a phased array antenna. Because it's an active antenna, and it's probably got quite a few DSP's in it to sort out all the antenna signals, I'll bet this antenna is going to cost signifigantly more than a plain access point. I really do think that what they're claiming is possible. It's not like it boosts the S/N ratio in the passive antenna sense. It's able to tease out and build a better signal by watching a great many tiny antennas. It's an awful lot of DSP horsepower to get that done, though.
I'll venture it'll cost about $800, which includes an integral access point. And they'll say "to get the same coverage, you'd need 8 regular access points, or 8 * $200."
Nothing new here. All it is is a phased array. By definition a phased array is directive, meaning it only covers a portion of the spherical space around the antenna. The reason this is good, is because directivity means gain. So yes, this new antenna will increase range, but only in a given direction. There are antenna schemes for 802.11b that get 10's of miles in range by using very directive antennas. There have been some articles on slashdot about this. The only interesting thing here is that the directivity is achieved by a phased array so it should be stearable. They may scan the 3 dimensional space (but this will cut availabitlity and thus bandwidth at any point). Or they may be able to stear multiple beams to point at areas with a concentration of devices. They may even be able to do it on the fly as demand changes, but there is no big breakthrough here. This technology is older than I am and probably older than most of you too.