[opendtv] Re: 200 Mile 8VSB Reception
- From: "Manfredi, Albert E" <albert.e.manfredi@xxxxxxxxxx>
- To: <opendtv@xxxxxxxxxxxxx>
- Date: Wed, 17 Jan 2007 15:43:34 -0500
John Shutt wrote:
> In the 1999 Sinclair Baltimore tests, WXXI (a PBS affiliate)
> tested both ATSC and DVB-T in the far field and found no
> measurable difference in reception.
Okay John. This time I was prepared.
To keep everything honest, in the 1999 Sinclair Baltimore tests, this is
what *Sinclair* actually said. As documented in FCC/OET 99-2:
"Sinclair indicates that the purpose of its 'far field,' i.e., beyond 30
miles, testing was to try to determine if a meaningful difference in
performance could be observed due to the differences between 8-VAB and
COFDM in threshold carrier-to-noise (C/N) ratio needed for acquisition
of service. It states that while there is a 4 dB difference in the
theoretical C/N performance between of the two systems in favor of
8-VSB, the average daily calibration threshold difference between the
8-VSB and COFDM receivers was 3.28 dB and that in the field this
difference shrank to 2 dB. Sinclair suggests that this may be due to the
effect of real world impairments that add to the theoretical 'gaussian'
channel values."
Theoretical: 4 dB
Instrumented: 3.28 dB
In field: 2 dB
These were 1st gen receivers, i.e. real-only equalizers, 0 to +15 usec
echo tolerance (or thereabouts), and so forth.
Bert
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:
- Using the UNSUBSCRIBE command in your user configuration settings at
FreeLists.org
- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word
unsubscribe in the subject line.
Other related posts: