[clug] Re: Wireless 802.11b

[Andrew Smith]

> I agree with Rohan,  Galaxy satellite dishes are very high gain
> omni-directional antennas focused to receive a signal sourced at >
50,000km.

Actually they were for the terrestrial feed from Black Mt.  They seem to be
similar to the Pacific Satellite G0300 series grids, my specs on them quote
a 20dBi gain in the ISM band (2.4GHz) and a 20degree beam width (30degree
elevation).

> However, you will certainly be able to do what you want with a hi-gain
omni
> directional (or sectoral) antenna on the hill and use the modified galaxy
> dishes (or just hi-gain directional antennas) at the customer/user end.
We
> have very successfully done this in both test and production environments
in
> both Canberra and Rockhampton.  If you do it right you can usually get
> >2Mb/s synchronous at up to 14Km with reasonalby priced off-the-shelf
> antennaes.

Just be carefull of the 36dBm output limit in this band.  With a high gain
antenna, you can only legally shove 16dBm into it, so maybe a 17dBm (50mW)
transmit power with 1dBm loss in the cable.

> By the way, if you are delivering Internet content over this make sure you
> have a carrier licence (or a nominated carrier declaration) or you will
get
> in big trouble. ;)

Only if it's commercial, otherwise it's exempt :)

http://www.aca.gov.au/consumer_info/fact_sheets/industry_fact_sheets/fsi29.htm

Andrew