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High-Gain Patch Antennas Boost Wi-Fi Capacity In Crowded Lecture Halls
An anonymous reader writes "To boost its Wi-Fi capacity in packed lecture halls, Georgia Institute of Technology gave up trying to cram in more access points with conventional omni-directional antennas, and juggle power settings and channel plans. Instead, it turned to new high-gain directional antennas. They look almost exactly like the bottom half of a small pizza box, and focus the Wi-Fi signal from the ceiling-mounted access point in a precise cone-shaped pattern, covering part of the lecture hall floor. Instead of the flaky, laggy connections, about which professors had been complaining, users now consistently get up to 144Mbps (if they have 802.11n client radios). 'Overall, the system performed much better' with the new antennas, says William Lawrence, IT project manager principal with the university's academic and research technologies group. 'And there was a much more even distribution of clients across the room's access points.'"
why cram all the bodies into the hall?
It is hardly newsworthy that a group of IT network techs 'fixed' their coverage and performance problems using directional antenna technology. Radio techs have been doing exactly that since they learnt about propagation. A newsworthy story would be that they have (finally) started incorporating at least basic RF theory in all IT networking related courses and subjects.
In Europe we limit the maximum radiated power (EIRP). This means you'd have to drop TX power and the directional antenna helps on RX only. Still might be worthwhile.
Although there is ample proof that WiFi don't have health issues, I still want to limit the EIRP. But to what level, I do not know. I think directional antennas currently have too strict a limit - you are not supposed to be standing next to a directional antenna anyway. OTOH people hardly understand what a 20dB antenna does (in TX).
This is a parroting of a marketing-derived press release. Move along. I think I'm going to move along. Thanks for the memories, Slashdot.
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IT guys fix their spotty wireless coverage by installing the proper antennas.
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Wow, thank God for that. Good thing that we have slashdot to tell us that a university installed some standard equipment on their campus. Be sure to run an article when MIT replaces a couple of their switches next month.
-1 disagree is not a modifier for a reason. -1 troll, flaimbait, redundant, overrated are NOT acceptable substitutes.
Well, they're "new" in the sense that they just purchased them, and knowing how much red tape there can be at universities, I'd say that is something to be impressed at.
Directional antennas are not new. But configuring an array of directional antennas to precisely cover the seats in the lecture hall to minimize the number of users on any single access point is a new and novel way to deploy wireless access.
Deploying the same number of omnidirectional antennas in the same space would lead to massive overlap, interference, and clients unnecessarily switching between APs when they perceived a stronger signal from a different AP.
I haven't heard of a high density environment purposely set up this way therefor I think it is indeed newsworthy.
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I read TFA, and did a search on that "bottom of pizza box" antenna.
Found it @ http://www.terra-wave.com/shop/font-colororangenewfont-245-ghz-14-dbi-high-density-panel-antenna-with-nstyle-jack-connectors-p-2993.html
The only problem is the price.
The cost of the antenna alone is $591.25 a pop.
Perhaps Georgia Institute of Technology has a big endowment, that they can afford to install such devices all over their campuses.
For most private enterprises, on the other hand, it's simply not affordable.
Muchas Gracias, Señor Edward Snowden !
You're just saying that with your IT hat on. The reality is whenever you start doing some tricky stuff just hand over to the RF guys and they can do precisely this kind of coverage work with their eyes closed. It's quite basic to build a system like this, IFF you know what you're doing.
It's always remarkable what people do with 802.11, but a lot of it strikes me as a mediocre standard being (over)extended with gimmicks.
Out of the box it works well enough for simple use, but more complex use cases (distance, density, broader coverage) seem to involve a lot of complexity to make up for the overall weakness of the standard (limited channel selection, radio power, etc).
Are there any changes on the horizon to generate new standards that would fix this? Such as designs tailored to high-density environments (hundreds or thousands of clients off a single radio), greater channel selections, better distance capabilities, etc?
I realize that not all of these may be something that works in a single product and that there are RF constraints that limit this, but at the end of the day the current 802.11 environment reminds me of DOS. Sure, with the right shims and magic you can run games (Quake, for the era) or a GUI OS on top of them, but there's something inherently hokey about it.