[at-l] OT (sort of)

[mbunz@telcordia.com (Marcus P. Bunz)]

sAunTerer,

You ask a very good question, and basically have the facts correct.

Cell Phones use pretty much line of sight transmission.  If you cann't see
the tower, you aren't going to get through.  (Slight exageration, you can
get through some buildings, and a few trees - just don't stick a hill in between.)

The problem is that the current base station equipment is fairly large - did you
ever notice the building next to the tower?  And that stuff isn't cheap.

I believe there are cell sights in the tunnels going into Manhattan, so that you
can use the cell phone when you are in them.

That may be the technology that is required.

At one point, many years ago, I believe I saw a view graph that indicated
radio sights could be connected to a mobil switching office via a Basic Rate
Interface.  That would be a very low capacity cell sight (two active calls),
and would have to be fairly cheap to deploy.

If the required equipment doesn't exist, it certainly can be developed.

The problem is pretty much one of economics.  On the plus side, as you've
pointed out, the right of way exists, you have power, phone lines, and you
don't have to build a tower or equipment hut.  On the minus side, you have
to pay for the pole space for the antenna, as well as the equipment enclosure.

The equipment would have to be able to handle extreme temperatures as
the cases bake in the sun, and freeze in the winter.  Power backup would
also be a problem.  I doubt there is a problem with interference from the
power lines, as this has been considered before.

Micro cell sites can be deployed within buildings to support Cell service,
but I'm not sure how far the equipment can be distributed - probably not
more than a few kilo-feet (thousand feet, for you non-telco folks).

The question really becomes why isn't cell service already in place.  Is it
because regulation prevented it, even in the face of strong lobbying on the
part of the wireless industry, or is the demand not very strong?  In the
first case, the industry might be willing to pay a premium for equipment
to increase coverage.  In the second case, if traditional equipment cann't
be justified, more expensive equipment isn't going to be installed.

Also, cell sights don't have to use the traditional tower.  I've seen water towers,
silos, and other buildings used as antenna sites.  There are also a few towers
that "look like trees" around.  It would be desirable for the "tree" to be a
little taller than the surrounding trees, but would not have to be 30-40
feet taller.

Hope this helps,

Marc

saunterer@jimbullard.org wrote:

  This is peripherally related since it involves maintaining the appearance
  of wilderness if not the fact.  Some time back when the subject of cell
  phones came up there were a couple of folks on the list with some
  telecommunications expertise.  My question is for them if they are still
  around.

  In the Adirondacks there is pressure to build cell towers and the
  Adirondack Park Agency has ruled that any which are built must be
  essentially invisible.  It's my understanding that towers are built tall to
  'reach over' as much as possible and cover as large a circle of area as
  possible.  As I drove through the mountains Sunday on my way to a symposium
  I wondered, is it technically possible to create smaller cellular
  receiver/transmitters that could be mounted on top of existing
  power/telephone poles and put them closer together so that smaller
  overlapping circles of coverage would allow cell phone coverage in
  populated areas and roadways without intruding on the wild areas?

  This would give coverage where it is perceived to be needed, be essentially
  invisible (the poles are already there),  and although it would require
  more units they would be substantially smaller, plus there would be no
  costs for additional land, access roads and towers.  Coverage is already
  there in the settled areas so basically we are talking about providing
  coverage in valley highway corridors that are blocked by
  mountains.  Perhaps my question  is mere technological ignorance but I read
  SMALL IS BEAUTIFUL many years ago and it continues to affect the way I
  think.  It seems to me that Americans (especially American engineers) tend
  toward *grand* solutions.  Perhaps a smaller scale solution would suffice.

  sAunTerer