[opendtv] Re: DVB-T HDTV demo using 19.7 Mbps in a 6 Mhz channel in costa rica
- From: "John Shutt" <shuttj@xxxxxxxxx>
- To: <opendtv@xxxxxxxxxxxxx>
- Date: Mon, 6 Mar 2006 10:01:24 -0500
----- Original Message -----
From: "Manfredi, Albert E" <albert.e.manfredi@xxxxxxxxxx>
> At that time, 1st generation receivers, this was robust
> enough to beat 8-VSB in indoor tests and when close to the transmitter,
> but the results far from the transmitter were not so different, or 8-VSB
> had the edge (a 4 dB advantage).
>
> http://www.tvtechnology.com/features/On-RF/dl_8VSB_vs_cofdm_part1.shtml
The distance reception demonstrations done by Sinclair in Baltimore in 1999
showed NO difference in far field reception between the two. The theortical
4 dB did not show up in practice.
http://www.hdtvmagazine.com/archives/pbsbalit.html
> The broadcasters might have a preference for DVB-T, if they want to use
> DVB-H to transmit to handheld devices on the same frequency allocation
> they use for DTT. Even though this will likely not lead to very good
> coverage. And also, that preference might be mitigated by the reduced
> coverage area of their DTT signal, at equal power and spectral
> efficiency.
And let's not forget HM-COFDM, where Stephen Long was tooling out in the
Nevada Desert at considerably higher than the speed limit, and Mark Schubin
couldn't lose lock except inside a closed metal transmitter cabinet on the
NAB floor. HM-COFDM was for robustness, while DVB-H is for low power
consumption and robustness, so I think a full power DTV station would have
plenty of coverage for such a device. We run power levels far above what is
run in Europe.
John
----------------------------------------------------------------------
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: