[RFI] alternative to PLC

Michael Tope W4EF at dellroy.com
Wed Jun 11 16:10:39 EDT 2003

> Yeah, but infrastructure is still required.  In some cases, the power
company has to run fiber to the neighborhood. In others, they use the MV
lines, but have to put digital repeaters about every 2000 feet on the line.
In others, they use 802.11 to get to the house.
> The premise that the infrastructure already exists is flawed.

That's why I was suggesting that MMDS technology
 would be a better alternative for rural areas. With MMDS,
all you need is the headend (typically about $1M) and
a $100 to $150 worth of  CPE (customer premises
equipment) for each subscriber. Nothing is needed in
between the headend and the sub except air, so as long
as you keep the headend up, you will have good system
reliability with the occasional truck roll for single customer
outages.  A 500' tower will provide a coverage circle of
about 40 miles in radius. I think the break even point for
these types of systes (at least when they are used to
delivery CATV type pay TV service) is at about 10 to
20K subs, so you can probably make a go of it with an
average suscriber density of 30 to 40 households/sq mile.
Below that subscriber density, it may not make economic
sense. Of course BPL, may not make sense either at
that level given that a non-zero amount of pole equipment
will be required (repeaters, couplers, etc). If repeaters
are needed every 2000', then it starts to look like a cable
TV system in terms of maintenance costs and reliability
I wonder if industry has any real viable business plans
for rural areas, or if they are just throwing hot air around to
sell the commissioners?

Another question about BPL technology. The articles I
read in the IEEE communications magazine suggest that
it is designed to be immune to "impulse noise", but they
don't really say whether or not this applies only to isolated
impulses (like the kind you get from contact closures) or
continous impulse noise like you get from leaky pole insulators.
If the modulation/coding  scheme they are using doesn't handle
the latter very well, then I think they are in for a system
maintenance nightmare if they start using MV lines
extensively. Anyone know about this?

73 de Mike, W4EF........................................

----- Original Message -----
From: "Hare,Ed, W1RFI" <w1rfi at arrl.org>
To: "Michael Tope" <W4EF at dellroy.com>; "George K. Watson"
<watson at sierracmp.com>; <RFI at contesting.com>
Sent: Wednesday, June 11, 2003 2:21 PM
Subject: RE: [RFI] alternative to PLC

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