On 26 Mar 2005 01:49:23 GMT, Bert Hyman <(E-Mail Removed)> wrote:
>In news:(E-Mail Removed) Jeff Liebermann
><(E-Mail Removed)> wrote:
>
>> Ham radio operators are allowed to use
>> much higher power levels on 2.4GHz than unlicensed users.
>Not all that much more power; only up to 1 W without automatic power
>control, but up to 100 W if APC is used. Of course, if APC is being used,
>the chances of actually running 100W is small.
Actually, that's only for 802.11 and 802.11b. You can go 1500 watts
with other modulation methods (i.e. frequency hopping). I know of
several high power 2.4GHz ham stations with big dishes. Mostly used
for 9600 baud satellite work.
http://www.qsl.net/kb9mwr/projects/wireless/pwr.html
>The big deal is that hams can use any sort of antennas they can dream up
>or get into the air. Since directional antennas are the order of the day,
>the opportunity for interference is minimized.
Yep. Directional antennas are a good thing.
>Whose fault is it if the 802.11 manufacturers chose to use an "unlicenced"
>band that was already occupied by a licensed service with rights to run
>high power?
Oh, assigning the blame is easy. The FCC had a problem. Hundreds of
manufacturers, inventors, hams, and experimenters had all these really
great ideas for communications. Just one problem, there were no
frequencies available for them to play. Most did their testing on ham
frequencies, but eventually everyone came to the FCC for an
allocation. Lacking the technical abilities to evaluate the merits of
all these proposals, and getting armtisted by corporate influence
peddlers, the FCC took the easy way out and dumped everything into the
ISM bands. I once saw a staff report claiming that the 900MHz ISM
band was "under-utilized". The theory was for each of these great
ideas to prove themselves in the ISM bands, and then the FCC will
consider allocating additional frequencies.
Well, along came the spectrum auctions and spectrum suddenly became
valueable. There was no revenue in unlicensed operation (spectrum
auctions are essentially license auctions). Predictably, there was no
spectrum for those not willing to pay for it. Meanwhile, much of the
spectrum was sold for pennies, while other spectrum went for prices
well beyond economical. The spectrum auctions soon became a fiasco.
Then, somone at the FCC noticed that the most successful thing they
ever did was to get out of the way and let the IEEE handle the
technical part of unlicensed wireless. This is terrible for the FCC
as it neither generates revenue or actually requires any FCC
involvement beyond rubber stamping type certification on equipment.
So, the FCC has finally, after 8 years of f*****g around, released a
fabulous 50MHz of former military bandwidth, with a minimum of
licensing (they just can't let go of the license game), and enough
grandfathered ground stations to make the spectrum useless in
metropolitan areas. Great praise should be given to the attorneys at
the FCC for having done this much.
So, what should a manufactory do with literally millions of customers
waiting for the FCC to throw together some sane spectrum policy? I
dunno. I seriously don't expect the attorneys that are running the
FCC to give much consideration any such technical considerations like
co-channel users, adjacent user protection, and service compatibility.
Spectrum is politically motivated, horded by the commissioners, and
technical considerations are secondary. (I can supply examples but
then this rant would last forever).
Bottom line is the manufactories did not "choose" to use 2.4Ghz. They
were told that it's 2.4GHz or go fly a kite by the FCC. Since two tin
cans and a string were not selling well, they decided 2.4Ghz was
better than nothing.
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice
http://www.LearnByDestroying.com
#
(E-Mail Removed)
#
(E-Mail Removed) AE6KS