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World Radiocommunications Group OKs New WLAN Spectrum
BenFranske writes "The World Radiocommunications Conference will allow a portion of spectrum in the 5GHz band to be used for WLANs, a decision hailed as a 'defining moment' for the WLAN industry. Although this doesn't impact the US much as this spectrum is already being used for wireless networking here, this will help standardize the frequencies worldwide."
Due to the nature of 5GHz waves it is very resilliant to interference.
Aroung 4/5 time the data carrying capacity of 2.4GHz band.
19 non-overlapping channels compared to the 3 non overlapping channels for 2.4GIG
A true multimedia experience is possible with the ability to stream video and hi-fi audio.
I'd love to see 5GHz transmitter be allowed greater power so we could reach comparable distances to that of 2.4GHz.
Bethanie: Whore...
Fan Whore
If you want more RF freedom, get an amateur license and have at it. Or don't, and just ignore the rules - either way it's not as if you were using this spectrum before, now is it?
Having a worldwide market for this stuff means cheaper end user product. That means MORE freedom because MORE people can utilize this spectrum. That means LESS crowding in populated areas. It also means even cheaper 2.4GHz equipment as the urban areas move into this new spectrum. That means rural areas (like mine) can even better afford wireless broadband.
Looks to me like this means more freedom all around. What planet are you from?
Actually, 5GHz won't affect humans nearly as much as 2.4GHz; a microwave oven operates at around 2.4GHz, where the 5GHz band does nothing useful/harmful on a macro scale.
If wireless networking ever does take off, this will be a huge boon... standardization is really the only way to ensure a future with interoperable global WLANs.. If only they did this with cellphones in the beginning.. instead of who knows how many different standards are around I wonder if any company has considered a SIrius/XM Radio like wireless internet connection? Would this be possible using satellites? What kind of speeds could be expected? Just some curious ideas I was pondering
Excuse me, I don't mean to impose, but I am the ocean
No big difference in heating between 2.4GHz and 5Ghz. 2.4GHZ is _not_ a "magical" frequency for heating water. See: http://homepages.ed.ac.uk/ah05/microwave.html
Its a shame that governments control the airwaves, but unfortunately in order for them to be of any use they sorta haveto.They regulate the airwaves as to reduce interferance that would otherwise jam just about every band. This way large corperate radio stations won't interfere with someone's remotely powered pacemaker. And SGI can't fry my pc's wifi card if I put my labtop next to their latest supercomputer. Its sort of a tragedy of the commons situation. The solution is to get rid of the commons by assigning ownership to them.
Well.. maybe. Or Maybe not. But Definitely not sort of.
From the page in question:
There is a clear maximum in the dielectric loss for water at a frequency of approximately 20GHz, the same point at which the dielectric constant ' goes through a point of inflexion as it decreases with increasing frequency. The 2.45GHz operating frequency of domestic ovens is selected to be some way from this maximum in order to limit the efficiency of the absorption. Too efficient absorption by the outer layers would inevitably lead to poor heating of the internal volume in large samples. This introduces the concept of skin depth or penetration depth, a subject which will be more fully discussed for conduction losses in Chapter 3, although the general principles discussed there apply to dielectric loss also.
802.11a uses part of the 5GHz band; now it can use more.
the PAL of 802.11a
Well, that depends on the antenna that is used. There is nothing inherent in the frequency or modulation that limits the signal propagation. If a direction antenna is used, then yes the signal will propogate much further in the orientated direction. With a linear antenna, like the small ones on most cheap 802.11 transmitters (or your 2.4ghz phone for that matter)the signal pattern of the antennae is more evenly distributed in each direction.
If you ask me (which nobody has), we should be using lower frequencies, not higher frequencies. Sure, lower frequencies require more bandwidth for the same speeds, but with lower bandwidths, obstacles wouldn't be a big deal, and you could transmit far, far further with less power as well.
I'm not talking Short-Wave radio frequencies, but rather, something like CB-frequencies, which can broadcast 5-10 miles from a portable handset (analog, with current bandwidth, presumably digital with a larger bandwidth could go much further) and base stations with antennas could potentially go up to 100 miles.
If you want a free network across an entire country like the US, you aren't going to do it on 2.4-5 GHz frequencies, but you could on much lower frequencies.
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Actually, 2.4 GHz is the frequency absorbed by water. That's why it's used in microwave ovens. It's also why it requires no licence - It is unuseable for commercial, government applications. As for 5GHz, it's absorbed by oxygen, another useless frequency. That's why 802.11a gets less range than 802.11b/g - there's always oxygen in the air, but moisture isn't always as abundant as oxygen
In Soviet Russia, the monkey spanks you!
>detail any downsides of using the 5Ghz band?
I'm no radio geek but...
As a rule of thumb the higher the frequency the shorter the range. Range and wall penetration are going to be much more important factors than thoroughput for almost all residental installs and many business applications. I believe the current estimate is you'll get 1/4 the range. Err, no thanks.
Its not exactly that simple. At the same distance 802.11a outperforms b. So if, and this is a big if, an 'a' client and a 'b' client are both at 175 feet or so then 'b' will get 2mbs and 'a' will get 6mbs.
What I think is starting to happen, that is if everyone doesn't just switch to a/b/g multicards, is that 'a' has a better chance of getting business sales. Businesses can afford to put up more APs to handle the range problems and could really use the extra bandwidth.
Home users will probably stick to 'a' (or 'g') as its range and penetration is a big plus. Bandwidth isn't much of a consideration when 99% of these users will just be connecting to a slow WAN pipe like a DSL line or a cable modem.
Neat little comparision chart here.
I just replaced (today) my Panasonic 2.4ghz phone that wa walking all over my wireless network at home with a ATT 5.8ghz phone....now I am hoping I dont have to go back to corded or a 900mhz phone. I know its in the lower range (like 5.2ghz) (the new standard)
http://www.jamesmcmurry.com
Sorry to burst your bubble, but WRC is a conference organized by ITU.