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[Discuss] satellite Internet vs. fixed wireless



Back in the late 90s there was a consumer fixed-wireless company here
in Boston, CAI Wireless. They used MMDS
(http://en.wikipedia.org/wiki/MMDS), now known as Broadband Radio
Service. CAI used frequencies in the 2GHz range and sent signals from
a few locations in the Boston area; the signal modulation used was
similar to cable modems. They offered one-way wireless service (the
uplink was a dialup connection) with a maximum download speed of about
1.5Mbps. (The tech could do a lot more; the limiting factor in
practice was the low speed of sending back the packet acknowledgements
over a 28.8Kbps modem.) There was a planned investment by Verizon that
was going to be coupled with a major increase in service rollout,
including two-way wireless tech that CAI was testing, but then Verizon
pulled the plug on the investment and CAI went out of business.
Current MMDS systems use DOCSIS modems that are close relatives of the
ones used for cable internet.

My house had the service; we were served from antennas on One
Financial Center. We had some reliability problems, mostly because
they had to put the microwave antenna on a 20 foot pushup pole to
clear some neighboring trees, and the pole was sufficiently flexible
that service would sometimes flake out in high winds. When they went
out of business we moved over to DSL service from Flashcom, which
later moved over to Speakeasy when Flashcom died.

MMDS is an awkward solution for a dense urban area like Boston. The
antennas need to have clear line of sight to the central site, which
means they have to be mounted on the roof in most cases, and so an
MMDS installation is not feasible on most rental housing. It could be
an effective solution for small cities and towns and rural areas,
especially where property ownership is the norm, though hilly terrain
could make it challenging to provide service in some areas.

Newer wireless solutions such as WiMAX (which is what Clear uses) and
LTE do not require line of sight. They use a different modulation
technique that is related to the one used in 802.11n networking and is
more tolerant of multipath, making it possible to use it in urban
areas and with indoor antennas, but the range of the radios is much
smaller if line of sight is not available. I believe the cost of the
equipment is now roughly comparable so a new fixed wireless deployment
would probably use WiMAX or LTE, as it would offer additional
possibilities such as mobile internet (impossible with DOCSIS modems).

We also until recently had wireless internet from Clear. The basic
problem here in Dorchester is that they substantially oversold their
service; the problem was reported repeatedly and persisted for over a
year, so it was clear that the company had no intent to build more
capacity to address the problem. As a result, they would slow our
connection to a crawl at busy times. We got 8Mbps on a really good
day, 3Mbps most days, but less than 1Mbps most of the time during the
busy evening hours. Lesson: WiMAX works well if you don't oversell
your bandwidth.

The Buttery finally had to give in to the dark side and get cable
internet from Comcast. (RCN doesn't serve our neighborhood and FIOS
isn't available in Boston.) I don't like having to do business with
Comcast, but the service works well.



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