Subject: [NEXTEL-1] Re: NYC Council members want radio repeaters in all hi-rises

From: Marcel <[email-masked]>
Date: Wed, 27 Nov 2002 12:17:34 -0500

------ Original Message --------
   From: Jack Daniel <[email-masked]>
Subject: Re: NYC Council members want radio repeaters in all hi-rises

Bob,

This report is actually about putting perminant signal boosters into
larger NY buildings.

You may not be aware that Motorola has an active program in place that
has been working this exact issue for some time.

Everyone has pretty much condemned running coax cable across streets and

sidewalks because of the high probablility of damage to the cables and
something else to trip firefighters. Also some other city fire
departments already have portable low-power repeaters in use.

There are several groups working the FDNY issue since 9-11, some
including me. It's not a simple matter and dozens of agencies and
business associations are working towards a mutually acceptable
approach. Things like fire codes, ordinances, building access, coverage
standards, financing, RF exposure safety and lots of other little
details have to be resolved.

There are even concepts of installing simple, self-healing, in-building
RF distribution systems that can take multiple cable/fiber breaks and
survive, eliminating the common failure nodes of conventional
in-building RF distribution systems. (Sorry, can't give any more details

at this time.)

One curious approach is an 'invention' by someone in NY recently which
is just a common portable linear amplifier. It has a marine battery
powering a low end power amp mounted in a metal suitcase. It works by
simply amplifing an attached portable's transmit power.

This is being called as "THE" $1000 answer to in-door coverage, capable
of talking to basements and the upper floors of a building from a lobby
or street level location. Field tests confirm it does improve indoor
communications, but I haven't heard of it being tested to handle digital

signals and other potential upcoming system changes.

It bothers me that this approach could develop into an unintentional but

very dangerous situation. Because it is being promoted as the universal
do-all in-building solution, firefighters will depend on it to deliver
full communications capability in EVERY building.

BUT........ such an approach would have had very little overall value on

9-11 due to the number of basements and number of floors. (besides,
investigations are also indicating radio hardware was NOT the primary
communications problem at the WTC.)

You simply can't carry aroung a powerful enough transmitter to do what
this device is supposed to do. Sure it helps in a lot of smaller
structures but when the user is depending on it in a large building they

are depending upon radio coverage this thing can't deliver.

This means the non-technical users will have to be educated to know
which buildings this will work in. This will have to be decided during
the stress of an emergency on a case-by-case, building type-by-building
type, understanding.

Firefighters need to know they have or do not have communications in a
structure; 'maybe' is a killer answer.

And I haven't even touched upon the unbalance of the system when the
transmit power is increased but the reciever sensitivity isn't. That
means the commander may be able to talk to his teams but they can't
report back. Imagine the confusion as team radios move in and out of
coverage, sometimes talking, sometimes not. Again, some benefit but
unpredicable coverage dependability.

And what about RF Exposure from the amplifiers antenna and the law suits

that will arise later, or the Hazmat potential of an acid spill or
explosive gasses from the large battery if it is damamged or overloaded.

OSHA will be all over this use.

I won't even go into portable antenna support assembly and placement.

I agree with pre-wired buildings (with or without signal boosters)
simply becuase it's the most reliable and predicable solution.

But I may be wrong..........
Jack daniel
============================================

BobC wrote:
>
> I wish I had thought of this...Actually I did.
> A few months ago I had thoughts about this only my idea went more
> along the lines of a distributed antenna system with leaky lines or
> even some waveguide put up alongside the building exterior and
> plumbed into alternating floors.
>
> The repeaters would stay with the fire vehicle and a port with power
> and coax fittings could be located on the building exterior. Perhaps
> where the fire dept could comfortably park and plug into for a length
> of time.
>
> At any rate I feel good that someone else envisioned a similar idea.
>

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