[opendtv] Re: 2VSB Status? (was Lawmakers Establish 2009 Deadline for Analog TV Phaseout)
- From: Richard Hollandsworth <holl_ands@xxxxxxxxx>
- To: opendtv@xxxxxxxxxxxxx
- Date: Sat, 24 Dec 2005 18:42:26 -0800 (PST)
Several months ago, we were curious whether any cable systems had ever used
16VSB mode (one person "thinks"....maybe...) and which ATSC Decoder chips
actually implemented the 16 VSB mode (latest Broadcom, LG and Oren for sure,
others are indeterminate):
http://hdtv.forsandiego.com/messages/2/3749.html#POST19808
So several of the chip manufacturers are still cranking out 16-VSB, even though
it never got off the ground for cable, in favor of 256-QAM.
The spec sheet for the LG 5th Generation chip (LGDT3303) and it's pin-for-pin
predecessor (LGDT3302, used in LST-4200A) can be found here:
http://www.fortetw.com/en/Product_vsb.htm
Note that it supports ATSC 8/16VSB as well as MMDS 2/4/8/16 VSB operation.
Hyundai GDS21D003 spec sheet (Mar99) also shows similiar operating modes:
http://www.ortodoxism.ro/datasheets/hynix/GDC21D003.pdf
MMDS is Multi-Channel Multi-Point Distribution System.
A means to distribute DTV signal to the Cable Headend, to the station
transmitter or to viewers like you.
http://www.rysavy.com/Articles/MMDS/MMDS.htm
http://en.wikipedia.org/wiki/Wireless_cable
http://wireless.fcc.gov/auctions/data/bandplans/mdsband.pdf
http://www.tech-faq.com/mmds-multichannel-multipoint-distribution-service.shtml
http://www.vmi-kc.com/html/mmds.html
ATSC D/53 only defines use of 8-VSB and 16-VSB for DTV.
However, I would suspect that several other ATSC Decoder chips might also
support 2/4/8/16-VSB MMDS modes, not mentioned in the ATSC spec sheets.
And the next gen ATSC Decoders would presumably also support E-VSB, which
employ 8-VSB packets embedded within the normal ATSC video program, but with
more robust coding.
<holl_ands>
==============================================
"Stephen W. Long" <longsw@xxxxxxxxxxxxxx> wrote: Does any one know the status
of 2VSB in the chips / specification for ATSC?
When my small group dared to say publicly that ATSC had no clothes, in a now
classic story, the lawyers on the ATSC side of the table insisted that robust
and mobile reception was going to be delivered via 2VSB. All of the 8VSB
receivers would have 2VSB modes and everyone would be happy.
I have not heard a peep about 2VSB since that time. Is it possible that
the 20 lawyers on the other side of the table that day that threatened to
sue me personally for delaying the DTV transition were not telling the
entire truth? Did they know 8VSB reception was problematic and that only 2VSB
could provide robust reception?
---------------------------------
Yahoo! Shopping
Find Great Deals on Holiday Gifts at Yahoo! Shopping
----------------------------------------------------------------------
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:
