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Surveying New Wireless Technologies
QuentinAxan writes "The Economist has a look at some of the ideas under consideration to advance wireless technology. I thought the concept of ad hoc architecture was especially interesting; the writers suggest briefly that it might encourage the creation of '"mom and pop" network operators, and small community networks.' (Which probably means that the telecom companies will crush it, but it's still a cool idea.)" We've touched on several of the ideas mentioned here before, but the Economist is always a good read.
Wasn't Michael's posting yesterday enough?. Its still on the front page.
The Gardener
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Ultra wideband to transmit 100 mbs wirelessly (but only for distances of 10 feet...).
Also accomplished by tossing DVD's back and forth....what's the point of that? I mean, only ten feet? Why not just use a cable at that point?
Come on, guys. You can do better than this. At least take a quick look at the front page every once and awhile.
we have been doing this for over a year now,
www.newgenwireless.com
IT works great, we stay on top of technology. We are currently running on 3 ISM Bands, 900, 2.4, and 5ghz systems. We get lots of business using this, and its MUCH more profitable than dial-up service.
you gota know what you are doing though, this isn't like throwing a computer together. You have to watch out for interference, know if you need to use FHSS or DSSS, if a band is too noisy, ect... Don't even get me on packet retransmissions due to trees and water!.
That with easier access to wireless internet, the /. editors will finally be able to NOT POST THE SAME THING MULTIPLE TIMES? This is truly the wave of the future ;)
using namespace slashdot;
troll::post();
Send Slashdot headlines to Timothy's cell phone so he can find out when his stories are repeats from yesterday.
Have fun: Join D.N.A. (National Dyslexics Association)
One of the advantages of ad-hoc over traditional (with an access point) is that, you don't need planning beforehand: you can have a network wherever 2 or more computers are close together.
The main disadvantage is that, since there is no planning, it is difficult to guarantee good quality of service: you can have coverage or not, depending on the conditions at that moment, the number of connected computers, how far they are, if they are moving or not...
Ad-hoc networks work great, as well, for expanding coverage area: in a true ad-hoc network, relaying is part of the system, so that spending money in expensive access points is not required as long as there are terminals (computers) that do the function.
One of the problems to be solved in ad-hoc networks, though, is that of billing: since every computer in the ad-hoc network is going to use its own resources for the benefit of others, how is this going to work? I mean, it is like giving free rides to others, that cost you money or time... In fact, this is how free software works, anyways... All in all, watch for more ad-hoc in the near future.
deaf.
One major reason experienced operators don't go after Smart Antennas is that their gain over regular antennas is only a few dB, usually between 3dB and 7dB. The improvement is easily cancelled out by it raining (-2dB to -4dB) which it does in Europe a great deal, the user changing polarisation by moving the phone from one ear to another (-3dB).
For 3G (Wideband CDMA) the name of the game is controlling interference from adjacent cells. Cell placement was good enough to do this for 2G, but 3G is far more sensitive to poor cell placement, with the effect felt over several cells. The way operators do this in practice is by planning the interference before placing the cell, or controlling it once the cell is built, or if it is built on an existing 2G site. Smart Antennas make simple planning very difficult, as the exact radiation pattern is not known, or more precisely it changes from one instance of the Monte Carlo simulation used for capacity planning a 3G cell to another.
Cell breathing due to high capacity, or high power mobiles are a few more variables that make the problem of planning and then running a 3G network far too complex for operators to take a bet on a few extra dB from Smart Antennas.