[opendtv] Re: "It can't be done"

  • From: "Manfredi, Albert E" <albert.e.manfredi@xxxxxxxxxx>
  • To: <opendtv@xxxxxxxxxxxxx>
  • Date: Thu, 28 Dec 2006 18:23:55 -0500

Craig Birkmaier wrote:

> Obviously Bert has no interest in the challenge. His
> pre-conceived notions about the viability of SFNs versus
> continuing to waste valuable spectrum with the current high
> powered ATSC big stick approach are keeping him from using
> his imagination and engineering skills.

I know you too well. When I thought about your likely response to some
real answers to your questions, I figured you would respond just this
way. Which is to say, if technically appropriate answers don't agree
with your mantra, don't adjust your vague notions, but rather tell the
other guy that his thinking is not as broad-visioned as your own.

Once again, to design an SFN that works along a narrow strip on the
coast is not that hard. But what makes it a really bad idea is that
reception to the east of this narrow strip will become far more tenuous
than it would be if you had implemented a network of translators. Or, as
I have said repeatedly, you can install a dense mesh of sticks to cover
the entire market. Not your usual vague response of three small sticks,
or similar. That won't create the sharp contours you seem to think are
desirable, nor will it cover the required area.

In order for FOTA TV to be competitive and self sustaining, you cannot
burden it with delicate and expensive infrastructure. Just as you cannot
burden it with too much "localism" in the content. You need to make it
simple and effective, and the content needs to be appropriate for mass
consumption. Every time you try to deviate from these simple basics,
IMO, all you're doing is encouraging the demise of FOTA TV.

In the past, I have gone to some effort to show you what your large area
SFN notions might lead to. One example was for Baltimore TV stations, to
provide what you consider to be the right cookie cutter coverage of
their existing market area (i.e. right up to the Delaware border and way
west of there too). But *my* intention in those cases was to show a
reduxio ad absurdum, not to egg you on. IIRC in the Baltimore market
area, it took between 38 and 41 sticks, not to mention that these needed
to be synchronized.

By the way, notice in the Qualcomm white paper that even with their mesh
of sticks, they have 15 Km wide dead zones in their Wash DC example.
Notice the 300 meter sticks and 50 KW ERP in their dense mesh. (Isn't
that what you recently called "earth scorcher"? Now you have a mesh of
these. Are you changing your tune?) The dead zone is what I said would
be a non-starter for FOTA TV nets. And I don't see anywhere in the white
paper that they intend for these networks to be FOTA. Or did I miss that

The French, the Dutch, the Germans, all seem to have come to the same
conclusion about using large area SFNs in FOTA TV networks. I guess they
all lack vision.

You can UNSUBSCRIBE from the OpenDTV list in two ways:

- Using the UNSUBSCRIBE command in your user configuration settings at 

- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word 
unsubscribe in the subject line.

Other related posts: