[FADCA] re: 802.11b/g Operations

[W4RP]

optimistic is correct -- we were on top of two causeways , 192 and eau
gaullie -- direct line of sight.

the bouy to shore link is line of site as well.

didn't mean to confuse the issue of general access point coverage.
trees suck -- literally,  at those freqs.

although, you can be surprised -- my atv repeater is on the harris tower at
300' with 1280mhz input (fm), and you can hit that baby with almost nothing
from about 7 miles (100 or so milliwatts) if you arent looking through
trees.

rick w4rp

----- Original Message -----
From: "Paul J. Toth-NA4AR" <ptoth1@tampabay.rr.com>
To: <fadca@mailman.qth.net>
Sent: Friday, February 14, 2003 4:01 PM
Subject: [FADCA] re: 802.11b/g Operations


> Rick and all....
>
> The HSMM is working on a number of different aspects of using DSSS
> technology above 900 MHz for digital networking and communications.  The
> hardware group is currently working on developing a recommended Hardware
> List for Radio Amateurs to build their systems around.  The software group
> is focusing on networking issues, applications and insuring the security
and
> integrity of the system while being in compliance with Part 97.  ?The
> massive proliferation of 802.11b devices operating under Part 15 offers a
> particularly interesting challenge for Amateur Radio that we seldom see in
> any of our other bands.  There are also legal and regulatory issues to
deal
> with to make this effort whole.
>
> Based on some experience in the commercial broadcast industry, I think the
> range estimates Rick offered are a little optimistic, particuarly here in
> Florida with all dense foliage and Summertime sub-tropical downpours.
> Getting the antenna above the treeline is paramount for any microwave
> signal.  "If you can see it, you can make the shot" was the philosophy we
> lived by in my Broadcast News days.  I believe we will be lucky to achieve
a
> five mile (5 mi) footprint radius in many areas for local access (User to
> Access Point).  This stuff just does not like trees!  It is also worth
> noting the commercial WISPs are using cellular-like antenna arrays at
their
> Access Points rather than omni-directional antennas.  Better gain and
> rejection of unwanted signals.  Point to point with two foot parabolic
> dishes, I look for fifteen miles.  Using separate RX and TX antennas
(which
> is possible with some Access Points, like Linksys, may enhance the hop
> distance a little.  The key on the Point-to-Point stuff will be to get the
> antennas (and antenna-mounted ampifiers) up in the air between 170' and
> 300'.  The 5.7 GHz band may actually be better for backbone operations as
> 802.11a will support connectivity up to 54 MBps.
>
> While there is still some room for Part 97 in the 2.4 GHz band, I believe
> Amateur Radio's real future is in the 3.3 GHz band.  There is virtually no
> Part 15 activity there at the present time to trashup the band.  If we can
> stake a claim first, our ability to use some power (>100mW) may help deter
> Part 15 activity.  The 2.4 GHz band is seeing so much activity in many
> metropilitan areas and Californai it's hard to squeeze a signal in
edgewise.
> In fact, a 2.4 GHz Amateur Radio voice repeater in California was recently
> turned off because it couldn't deal with the interference from a nearby
> 802.11b Access Point.  The ARRL is investigating this situation.
>
> One other point worth noting.  In my presentation last Saturday at
Orlando,
> I noted a third potential area for development and activity...the 'Last
> Mile" for EComm (or EmComm, if you prefer).  These high speed links offer
us
> the ability to do voice, video and data simultaneously, if we have the
right
> equipment on both ends of the link.  That means a Red Cross Field
Operation
> could have their telephones and computer data routed over the same link.
> This is something to look at for supporting hospitals during a disaster.
>
> Thanks to Doug-KN4YT for his comments this morning about ESATCOM.  Tying
all
> this together with satellite links is the ultimate high speed wireless
> solution.  Until then, bring on the HF Pactor station that can route
> messages to gateway stations.
>
> 73 de Paul-NA4AR
> ARRL HSMM Working Group
>
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