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Archived
Tech-Notes
Published by: Larry Bloomfield & Jim Mendrala
The following are our current e-mail addresses:
E-mail = hdtvguy@garlic.com
or J.Mendrala@ieee.org
We have copied the original Tech-Notes below as it
was sent out. Some of the information may be out of date.
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Tech Notes
Published by: Larry Bloomfield & Jim Mendrala
E-mail = HDTVGuy@aol.com or J.Mendrala@ieee.org
November 16, 1999
Tech Note - 044
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Talent does what it can, but genius does what it must!
Our Mission: Sharing experiences, knowledge, observations, concerns,
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Subj: Deja Vu - The 12-inch
Disk
By: Larry Bloomfield
There aren’t too many broadcasters still around who remember the days
of the 12-inch LP, but don’t look now, the 12-inch LP disk may be
making a comeback, but not in the old familiar black vinyl form.
According to an article that appeared recently in the San Jose Mercury
News, “Japanese government researchers and Sharp Corporation have
developed a memory disc that can store 40 times more data than a digital
video disc (DVD).” Based on what Nobufumi Atoda, Chief Scientist at
the Japanese National Institute for Advanced Interdisciplinary Research
(NIAIR) said, it is possible to store up to 40 movies, each two hours
in length on a single 12-inch (30.5 cm) disc. Today’s DVDs hold about
4.7 gigabytes of information, but the new disc can store upwards of
200 gigabytes, according to Atoda.
NIAIR is a part of a Japanese governmental Science and Technology
Agency who will work jointly with Sharp and three other unspecified
Japanese companies to produce prototypes of the new technology over
the next few.
Just when some people were saying that the Laserdisc is dead, news
of this kind surfaces. The San Jose Mercury article referred to the
new disc as being a “long playing” disc. That coupled with the fact
that the disc is a 12-inch device, sure does bring back memories and
puts a whole new meaning to the term “12-inch LP.” Could we then call
this new disk a CD-LP?
Despite the seemingly endless applications for this kind of technology,
one can’t help but wonder how such a device will stack up against
hard drives, which seem to have no limit to their capacity, as technology
improves, and their cost per gigabyte keeps plummeting. In comparison
though, hard drives are not quite as portable as a single CD would
be; large or small. When this new CD-LP system hits the
market, if it is “rerecordable,” it will be an even more serious competitor
to the hard drive.
It should come as no surprise if Sharp targets this new 200 Gbts optical
format for the distribution of HD program material. Here’s the math:
An uncompressed feature-length film recorded at 1920 x 1080p resolution
requires about 1200 Gbts of space, (i.e. 30 bytes/pixel x 2 Mpixels/frame
x 24 frames/second x 60 seconds/minute x 140 minutes). Using nearly
loss less 6x wavelet compression, the new 12-inch optical disk format
could very reliably support this kind of application. . Jim Mendrala,
Vice President at Real Image Digital said: “The recent digital screening
of Star Wars, used 20 18 Gbts hard drives in the Pluto array for its
presentation.”
The 12-inch, 200 Gbts optical storage technology is an approximate
seven times increase in usable disk surface area, over the conventional
DVD (i.e. ~105 sq. in. for a 12” disk versus ~15 sq. in. for a 4½
in. disk). Based on improvements in laser diodes, announced over a
year ago, a blue laser pickup, if used, permits the increase in bit-density
over conventional red lasers currently used in DVD players, by nearly
six times.
Considering that the new CD-LP, at 12-inches, it isn’t quite as space
efficient as a standard DVD disc, at slightly more than 4½ inches,
its potential use must be taken into account. If you think in terms
of a library, there is no reason you couldn’t store copious amounts
of data, as would be the case with a high definition movie, or the
stated 40 standard definition movies in significantly less space than
is the case with individual standard CDs. With Firewire as the interconnect,
there is no reason why stations couldn’t get HDTV movies, or other
material,
either delivered through normal FedEx or via Satellite and use this
media as the basis of either long term or short term storage.
Here’s an interesting scenario: When the General Manager and Program
Director return from NAPTE, they could very well have one of the new
CD-LPs in their knapsack with several seasons worth of syndicated
half-hour shows on it.
When Sharp, here in the US was contacted for further information,
their spokesperson said that although Sharp US is aware of the various
ongoing technology research projects in Japan, they were not in a
position to comment on this one, at this time.
In any event, an associate mentioned a Bette Davis comment she made
over sixty years ago, which certainly applies to television today:
“Fasten your seat belts; it’s going to be a bumpy ride.”
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Subj: Zenith Woe’s
By: Larry Bloomfield
Just because you hold a large number of patents in the wonderful world
of digital television and are a charter member of the Grand Alliance
does not make you necessarily immune to financial woes. Plagued with
ongoing financial troubles, Zenith has been in the process of restructuring
so that it can stay alive and in business. “Zenith is entering the
final phase of its restructuring, designed to transform us into a
technology, marketing and sales company,” John Taylor said.
Zenith, a company who has been on the consumer side of the broadcast
scene since the early days of radio, and know more recently as makers
of television sets, VCRs and their excursions into digital television
has lost market share in the area of their manufactured goods. To
seek protection from their creditors, the Glenview-based company filed
Chapter 11 in U.S. Bankruptcy Court in Wilmington, Del., as one of
their final steps in their restructuring. “The prepackaged reorganization
plan filed in late August has the strong support of our creditors
and is expected to move through the process quickly, in just a matter
of months,” said Taylor. This move should come as no surprise as Zenith
announced last year that it would file for bankruptcy after coming
up with a turnaround package that would essentially remake the company.
This move will position Zenith so they can better take aim at reducing
debt and de-emphasize the manufacturing side of their organization.
LG Electronics of South Korea, which owns 55 percent of Zenith’s outstanding
shares, acquired its majority interest in November 1995 and has agreed,
as part of the restructuring, to exchange $200 million of its debt
claims for 100 percent ownership in the new, reorganized Zenith.
To hold things at bay, Zenith, earlier this year obtained a $300 million
line of credit from Citicorp North America, Inc. to cover its debts
during its restructuring. LG Electronics, who has a moderate presence
in San Jose, CA, could not be reached for comment. “When the restructuring
is completed, Zenith will be in an even stronger position to capitalize
on its digital
technologies like HDTV, Taylor concluded.” For more information about
Zenith, visit their web site at www.Zenith.com
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Subj: SkyTune and Sarnoff
Corporation Develop Next-Generation Digital TV Receiver for PCs
From: Jeff Urquhart of Voce Communications
SkyTune and Sarnoff Corporation today announced an agreement to develop
products which will allow personal computer and information appliance
vendors to build low-cost digital television (DTV) and datacasting
reception capabilities into their products.
SkyTune is a manufacturer of DTV and datacasting receivers for personal
computers and information appliances. Sarnoff pioneered datacasting
as part of its role in developing the DTV/HDTV technology for the
ATSC (Advanced Television Systems Committee) standard.
Under the agreement, SkyTune will incorporate Sarnoff’s latest approaches
for reliable reception of ATSC DTV broadcasts into jointly developed
products specifically for the PC and datacasting information appliance
markets.
“Digital television and datacasting are going to change the way the
world views the Internet and television," said Dr. James E. Carnes,
Sarnoff president and CEO. "We're confident that our collaboration
with SkyTune will play an important role in building this new medium
by creating the technology PCs need to tap its potential. Reliable
reception of DTV signals on PCs will quickly establish a mass-market
audience for digital video and broadband datacasting.”
The alliance will merge Sarnoff’s DTV reception know-how with SkyTune’s
PC architecture and Windows expertise. The initial device, the SKY5201,
will be the foundation for a family of low-cost, PC-centric ATSC broadcast
receivers. Engineering samples of receivers based upon the SKY5201
will be available mid-2000.
Goals of the SkyTune and Sarnoff collaborative effort include:
· Enabling low-cost PC reception
of ATSC digital and NTSC analog broadcasts through a single-chip integration
of an NTSC decoder, comb filters, and 8-VSB demodulation with widely
supported PC buses such as PCI and 1394.
· Creation of new applications for
consumers and broadcasters such as broadband datacasting, music and
streaming video delivery, and enriched, interactive television broadcasting.
· Development of Internet-aware datacasting
solutions that intelligently cache broadband audio, video and data
through metadata extraction and user profiling.
· Standardization of ATSC reception
and DTV software decoding features within consumer and entertainment
PCs.
“The SkyTune and Sarnoff alliance adds more credibility to the bright
future of ATSC Digital TV,” said Gerry Kaufhold, Principal Analyst,
Digital Television, at Cahners In-Stat Group. “The joint development
will accelerate this deployment for the initial market of datacasting
and raise expectations moving into the 21st Century.”
“The partnership with Sarnoff establishes SkyTune as the leading manufacturer
of PC-centric ATSC digital television datacasting receivers,” said
Richard Johnson, SkyTune president and CEO. “The combination of Sarnoff’s
DTV and datacasting expertise with SkyTune’s PC, software and datacasting
talents provides us with the capability to manufacturer the best products
on the market and enable exciting new services for broadcasters and
consumers.”
“We support SkyTune and Sarnoff’s joint efforts to make the next-generation
of digital television and datacasting technology more accessible and
affordable to PC users,” said Clint Chao, vice president of marketing
for SkyStream Corporation, a broadcast networking infrastructure provider.
“Datacasting is poised to take off as the transport medium of choice
for Internet and television content providers. The wide availability
of digital television and datacasting receiver technology will promote
and speed up the development of exciting new content and applications
for sending Internet and data content over broadcast networks.”
For additional information, contact: jurquhart@vocecommunications.com
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Subj: The 8VSB - COFDM Sinclair issue
From: Mark A. Aitken, Advanced Technology Group (a part of the Sinclair
Broadcast Group)
In an attempt to get everyone “on the same page”, I will try to “demystify”
the issues being raised by some.
“Why is Sinclair asking the FCC to ‘abandon’ 8VSB?”
This IS NOT what Sinclair has requested in its filing. The following
list details Sinclair’s primary position with respect to the filing:
What Sinclair Is Asking the FCC To Do?
1. Modify the digital modulation standard so broadcasters can transmit
their digital signals using Coded Orthogonal Frequency Division Multiplexing
(COFDM).
2. Appoint a COFDM Task Force that would be assigned two responsibilities:
A. Conduct a study and issue recommendations to the Commission regarding
the integration of COFDM digital modulation technology into the DTV
standard; and
B. Conduct a rigorous scientific analysis to determine the interference
ratios for COFDM transmissions into existing NTSC and 8-VSB DTV signals.
3. Adopt rules implementing the recommendations of the Task Force.
What Sinclair Is Not Asking the FCC To Do?
1. Abandon 8-VSB as a digital television modulation standard.
2. Delay any of the time deadlines for the DTV rollout.
Why Should the FCC Allow Broadcasters To Operate Using COFDM Technology?
1. Use of COFDM digital modulation technology will permit reliable
and robust over-the-air reception by viewers using simple antennas
in broadcasters’ core business areas.
2. Use of COFDM would enable broadcasters to provide mobile and portable
DTV video services.
3. By permitting COFDM operations, the Commission will allow the marketplace
to play an appropriate role in the development of broadcast technology.
Permitting use of COFDM would make the U.S. DTV system compatible
with the DTV technology adopted in the majority of countries around
the world.
A decision by the Commission to permit COFDM operations would accelerate
the development of DTV in the United States and speed the recapture
of NTSC spectrum.
What’s Wrong With The 8-VSB Digital Modulation Standard?
1. The ATSC 8-VSB standard does not currently permit reliable over-the-air
reception of DTV with simple antennas in broadcasters’ core business
areas, or permit portable or
mobile services.
2. Given the reception problems, continued reliance on the 8-VSB standard
would diminish viewing functionality and impose unnecessary costs
on U.S. consumers, both during and
after the DTV transition.
Are there Legitimate Technical or Economic Reasons To Preclude Broadcasters
From Operating Using COFDM Technology?
1. There is no legitimate technical reason precluding the use of COFDM
modulation technology.
A. COFDM signals can be used to provide HDTV over 6 MHz channels.
B. The greater coverage predicted for 8-VSB signals in a laboratory
environment does not hold up under real-world conditions.
C. The Commission should not perpetuate exclusive reliance on the
8-VSB standard based on any speculated improvements in 8-VSB receiver
technology.
2. Broadcasters, manufacturers, and consumers would incur only minor
costs if the Commission decided to permit use of COFDM in the U.S.
A. Any additional costs for broadcasters would be borne voluntarily,
and would likely be inconsequential.
B. Grant of the instant petition would not impose significant costs
on DTV receiver manufacturers.
The prior sale of 8-VSB receivers to a tiny fraction of consumers
should not prevent the Commission from permitting broadcasters to
use COFDM technology.
“What about the extra power required by COFDM? ”
Some 8-VSB proponents have stated that a COFDM transmitter will need
to operate at significantly higher peak and average powers to achieve
the same coverage as an 8-VSB transmitter. Increases of up to 7dB
have been quoted; the implication being that the initial transmitter
capital acquisition costs and the ongoing expenses associated with
power consumption will be much higher for the COFDM transmitter. Ergo,
a change to COFDM will cost the US Broadcaster huge sums of money.
This is just not true and needs to be examined from both the peak
and average power perspectives.
Peak power: COFDM does have a higher peak to average ratio than 8-VSB.
However the actual peaks occur for very short periods and both systems
can tolerate a reduction of the peak to average ratio without significant
distortion. Certain digital signal manipulation techniques currently
being deployed take advantage of the inherent robustness of the multi-carrier
COFDM format to provide a greater reduction in peak to average ratio
than is possible for the single-carrier 8-VSB signal. The resultant
peak to average ratio “penalty” of COFDM is
reduced to about 1dB. This may result in a slightly higher initial
purchase cost for a solid-state transmitter due to a higher device
count, but it is unlikely to have any impact on the cost of a
high power vacuum tube transmitter.
Average Power:
For equivalent data rates, 8-VSB would appear have a theoretical C/N
“advantage” of about 4dB over COFDM. This “advantage” is often used
to justify the claim that 8-VSB will provide greater coverage than
COFDM operating at the same average power. The theoretical advantage
can, in fact, only be confirmed in a laboratory environment. When
real world signal propagation and reception characteristics, such
as static and dynamic multi-path, are factored in, the “advantage”
evaporates into the ether! Sinclair tested and demonstrated the
ability to receive COFDM signals at the far fringe coverage areas
with no meaningful differences when compared to 8VSB signals at the
same average power. Given the realities of a typical fringe reception
environment, any small difference is of little relevance when compared
to:
Antenna downlead losses (6 dB)
Diurnal fade margins (6 dB)
Modern fringe antenna gains (+12 dB to +16 dB)
Low cost and effective “Low Noise Amps” (~2.5dB NF@13-20dB gain)
Under real-world conditions, there exists no meaningful or material
difference in the receivability of 8VSB and COFDM signals. We see
absolutely no reason why higher average power transmission would be
required by COFDM.
“Will COFDM have a major (negative) impact on the FCC table of allotments?”
The FCC revealed in its recently released OET Report 99-2 that the
most highly congested “Top 10” DTV markets were studied to determine
the impact on the table of allotments and differences in service availability.
In the FCC OET analysis they assumed:
COFDM to have an advantage in urban areas close to the transmission
facility, and 8VSB to have an advantage in fringe area coverage.
As well, they assumed (incorrectly) that COFDM would have to operate
at an increased power level of +4dB (see above).
Under these conditions the FCC OET found that: The estimates indicate
that the relative advantages/disadvantages of the systems have a “generally
small” impact on the overall coverage, and vary by market. The interference
to NTSC service, even when providing for an additional +4dB of power
by COFDM, would be “generally small”.
“What is the cost impact to convert 8VSB transmission systems?”
Clearly, the cost will vary from various system providers. In general,
the conversion of an existing 8VSB transmitter at similar or equal
power levels will typically be less than $50,000, the cost of integrating
and setting up a new modulator. In many cases, where the equipment
provider is also supplying COFDM equipment to the global market, the
conversion may be significantly less than $20,000 (the cost of an
exciter modulator card swap and setup). In the case of equipment such
as encoders, there are similar variables. Many of the encoder
manufacturers/providers are supplying exactly the same hardware for
8VSB and COFDM markets, with a simple requirement of software or firmware
revisions.
We would like to thank you for the support that you have shown during
most recent period. Your support and informed understanding of the
issues at hand is shaping the course for the
future of digital television broadcasting.
If you have questions, please visit our site: www.sbgi.net. You will
find a link to DTV information, and may also address any your specific
concerns to dtv@sbgi.net.
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Subj: KGTV-DT
Date: 10/29/99 3:38:16 PM Pacific Daylight Time
From: Margie Baldwin
KGTV-DT successfully met the Nov 1st deadline. We were 1st in the
market to roll out DTV on 9/13/99 with Monday Night Football from
ABC and the only to meet the FCC deadline! The rest of the local competitors
asked for extension. I share this with you, because of our last conversation.
My team and I did it!
Marge Baldwin - Engineering director, KGTV-DT
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Subj: Speculation and food
for thought
From: Larry Bloomfield
There are 1599 full power television stations on the air in the US.
Of this number 370 are non-commercial. That means that by the first
of this month, November, no less than 1229 should have filed for a
construction permit to make the transition to digital television.
Check the math against the FCC’s web page at: http://www.fcc.gov/mmb/vsd/files/dtvsum.html.
Am I mistaken or are there quite a few stations that haven’t bothered
to file for a construction permit? This is the step necessary to make
the transition. Are they tired of being in broadcasting? I’d give
anything to have any one of them who have blown the November 1st date
to give me a call and tell me why!
Here’s the summary of DTV applications filed as of November 10, 1999
directly from the FCC web page.
For all markets: 600 (35% of) - TV stations have filed DTV construction
permit applications (actual cases received by the Video Div. and entered
in CDBS.
220 of those stations have been granted DTV Construction Permits -
83 are on the air with full facilities. 25 others are on the air with
special or experimental DTV authority.
The remaining applications are awaiting database entry; additional
information; Mexican, Canadian or other clearances or are the non-checklist
or maximization type. These applications are currently being processed
in proper priority order.
Top Ten Market Network Affiliates
39 out of 40 of these stations, which had a May 1, 1998, filing deadline,
have filed applications; all 39 have been granted CPs - 32 are on
the air with full facilities. Eight have requested second extensions
of time to go on the air.
All of the top ten cities have at least one full facility DTV station
on the air.
Markets 11 - 30 - Network Affiliates
78 - out of 79 of these stations, with an August 3,1998, filing deadline
have filed applications; 72 have been granted CPs - 3 others have
been granted STAs to operate while action on their applications is
pending - 35 are on the air with full facilities 41 have requested
extensions of time to go on the air.
In closing, I’d like to know if it costs anything to be so stupid
or does it come naturally. There is no excuse for not filing!
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(Ed Note: The Editors and Publishers of the Tech Notes
wish to thank Des Chaskelson, Research Director of SCRI International
for his generosity in posting the Tech Notes on the SCRI web site.
www.SCRI.com).
From: Des Chaskelson, Research Director, SCRI International
(des_chas@scri.com)
Re: New Website with Industry Press Releases Plus New HDTV Survey
Check out the SCRI web site, where the Tech Notes are published, for
some really great information on industry trends and other very valuable
marketing information, trade news and current television events. SCRI
is currently in preparation of our latest survey, analyses and report.
Stay tuned!
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The Tech Notes are published for
broadcast professionals, and others, who are interested in DTV, HDTV,
Electronic Cinema, etc., by Larry Bloomfield and Jim Mendrala. We
can be reached by either e-mail or land lines (408) 778-3412, (661)
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END
