RF CURRENT
Welcome to RF Current, a weekly electronic newsletter focusing
on Broadcast technical and F.C.C. related issues. This newsletter
is part of The RF Page @
www.transmitter.com, a web site devoted to TV Broadcast RF
engineering. For more information see the What
is... guide to the R.F. Page site.
This page contains stories from RF Current issues published in November 1997. Links referenced in the articles
were current when published but by this time may have changed. If you find a bad link, try connecting to the
home page of the publication or company and look for an archive of past articles. If you find a changed link,
I'd appreciate it if you'd let me know by dropping me a note indicating the new location
at dlung@transmitter.com.
I'm looking for news from shows and meetings or news from your
company that might be of interest to other RF and broadcast
engineers. Please e-mail me at dlung@transmitter.com or
phone me at Telemundo, (305) 884-9664.
NOTICE: RF Current was not be published December 1st. Items up to
the U.S. Thanksgiving Holiday will appear in the November 26th Extended
Edition.
November 26 - Issue 96 Extended
Edition
- FCC Announces Auction Schedule - Proposes Broadcast
License Auction Rules (Nov. 26)
- In a Public
Notice (DA972497) released yesterday the FCC outlined
its auction schedule for 1998. The first auctions will be
for the LMDS spectrum, with an application deadline of
January 20, 1998. Broadcasters will be interested to note
the FCC listed a "Pending Analog Broadcast Licenses
for Commercial Radio and Television Stations"
auction in the 4th Quarter of 1998. See the Public
Notice for more details.
In a separate action, the FCC adopted a Notice of
Proposed Rule Making that would substitute auctions for
comparative hearings in deciding mutually exclusive
broadcast license cases. The Balanced Budget Act of 1997
required the use of auction in new cases. It allowed the
Commission to choose which method to use in pending
cases. In the NPRM the Commission asked for comments on
whether it should hold comparative hearings instead of
using auctions in pending cases, particularly those in
which an Initial Decision had been issued before the D.C.
Circuit Court invalidated the Commission's central
criterion for deciding the cases.
The FCC also announced a temporary freeze, effective upon
release of the NPRM, on the filing of applications for
commercial broadcast stations. Noncommercial broadcast
educational licenses would not be subject to auctions,
although the NPRM requested comments on whether ITFS
licenses should be included in the auctions.
More details are available in the News
Release (NRMM7020). The Notice of Proposed Rule
Making was not available on the FCC's web site when this
was written. The WordPerfect version should appear at https://www.fcc.gov/Bureaus/Mass_Media/Notices/1997/fcc97397.wp
. The FCC often releases NPRMs in other formats. Try
these predicted links for text,
Adobe Acrobat
or HTML
formats.
- TV CEMA Urges FCC to Alter Proposed V-Chip
Implementation Rule (Nov. 24)
- The Consumer Electronics Manufacturers Association (CEMA)
urged the FCC to "set reasonable implementation
deadlines for the so-called V-Chip". Gary Shapiro,
President of CEMA, said
"The
FCC has to recognize that merely because it adopts the
programming standard does not mean manufacturers can
change production schedules overnight. Given the normal
TV production cycle to meet the Commission's proposed
July 1998 deadline would have required manufacturers to
begin the product development process back in January
1997. The Commission's deadline would require
manufacturers to reduce the design cycle from 18 to six
months, and that is not possible. There is more to
designing a new televsion than just changing a few
circuits. It includes designed the new integrated
circuits, and a workable user interface, laboratory
testing, as well as developing a field test and quality
assurance regimes. And forcing manufacturers to radically
compress the manufacturing and testing process may cause
hte introduction to the marketplace of a program blocking
feature that is less than functional."
CEMA also called on the FCC
to make clear that the program blocking rules do not
apply to Internet content, and that computers do not
require a V-chip unless they can receive television
signals and have a monitor of 13 inches or larger. More
details are available in the CEMA
News Release.
- DTV News from SMPTE Conference in NYC (Nov. 24)
- At the SMPTE 1997 conference in NYC, Victor Tawil
reported on the preliminary results of field strength
tests at WHD-TV, the Model HDTV station in Washington
D.C. Looking at the preliminary test numbers, it appeared
coverage was far less than that obtained at similar DTV
tests in Charlotte, NC and Raleigh, NC. Power wasn't the
problem, as Tawil said the station was operating at 500
kW average ERP. The antenna height (under 500 feet),
combined with reflections from nearby towers and
buildings, appeared to be the main cause of the coverage
problems. Multipath alone wasn't the issue, since over
twenty percent of the sites had signal levels below
threshold. Additional tests are planned in December using
a different antenna and circular polarization. It will be
interesting to see how this affects the coverage.
Bob Rast reported on CBS's DTV activities. During the
application process for WCBS-DT in New York City, the FCC
discovered that in some cities the current DTV Table of
Allotments did not consider the 400 km. coordination zone
with Canada. This has the potential to impact DTV channel
assignments throughout the northern part of the U.S.,
particularly in the Northeast. Whether or not this will
delay the expected January release of the FCC's new DTV
Table of Allotments is not known at this time. The FCC is
under pressure to act on the Petitions for
Reconsideration filed earlier this year and finalize the
DTV Table so stations can plan for construction. Even if
the Table is released in January it is likely it will
take at least an additional 60 days to consider comments
on it.
Audio tapes of these sessions are available. Victor
Tawil's report and the rest of Friday's day-long seminar
are available in a 7 tape package, Reference the Friday,
November 21, 1997 seminar. Price quoted at the show for
the tape set was $59, this may be higher for orders
placed now. Bob Rast's report was part of an extremely
informative panel discussion titled "DTV as a
Business", a two tape set, number P1. Price for
these two tapes is $24. Orders should reference meeting
number SM9701. The company providing the tapes is
Conference Copy Inc., 8435 Route 739, Hawley, PA 18428.
Telephone (US) (717) 775-0580, fax (717) 775-9671.
While these sessions were not included in the
Proceedings, most are. For information on ordering copies
of the 1997 SMPTE Conference Proceedings, visit the SMPTE web site.
- FCC Experimental Actions in October (Nov. 21)
- The FCC has released a Public
Notice on Experimental Actions, listing licenses
granted in October, 1997. Interesting grants include an
experimental license to CBS Communications Services, Inc.
(no apparent connection to the broadcasting company) for
a wide range of frequencies, including 138-140 MHz.,
150.05-174 MHz., 216-222 MHz., 410-413 MHz., 450-512 MHz.
(includes TV auxiliary frequencies), 806-824 MHz.,
851-869 MHz., 1710-1850 MHz. and 2450-2483.5 MHz, The
purpose is to test, develop and demonstrate
communications and surveillance equipment for Federal,
state, and local governments. The locations are fixed and
mobile in Fort Lauderdale, Florida and the continental
United State.
COMSAT RSI, Wireless Antennas, was granted a license
(WA2XNC) to operate in several frequency bands, including
420-608 MHz., 614-959.6 MHz., 3700-4200 MHz., 5725-8400
MHz., 10700-13250 MHz. and 17700-19700 MHz. Several other
bands were also listed, but those above include
frequencies of interest to broadcasters - TV channels,
C-band downlinks and uplinks, TVAuxiliary, and Ku-band
downlinks and uplinks. The station will be fixed in
Antioch (Lake), Illinois.
For more information on these grants as well as a
complete list of all experiment licenses granted in
October refer to the Public
Notice (pnet7025.txt).
- TECHNOLOGY - Researchers Build World's Smallest
Practical Transistor (Nov. 19)
- If you follow news on computer and communications
integrated circuits, you've probably seen reports we may
be reaching the limits of physics in our attempts to
build smaller, faster ICs. Researchers at Bell
Laboratories have succeeded in creating experimental MOS
"nanotransistors" that are only 60 nanometers
wide. How wide is 60 nanometers? According to the release
from Lucent, 182 atoms wide, four times thinner than the
smallest transistors in today's ICs. The nanotransistor
delivered a current flow of 1.8 milliamps per micron in
the "on" state at 1.5 volts. Lucent's Press
Release said "It also delivered the highest reported
transconductance - a measure related to the transistor's
gain - at 1.12 siemens/mm. It is five times faster and
draves 60 to 160 times less power than today's
transistors to perform equivalent operations." The
160x figure is obtained with the device operating at 0.6
volts.
More information on the "nanotransistor" is
available in the Lucent
Press Release and in the Technical
Data. Photographs
are also available.
- CHIPS - Sony Announces Line of DTV Receiver Chips
(Nov. 18)
- Yesterday sony announced a services of chips designed for
use in various digital TV applications. Two of the chips
work as a tuner for digital broadcast signals from
satelllite. One chip is an oscillator/mixer circuit that
includes an oscillator stable over 1.3 to 2.7 GHz. The
other chip provides adjustment free carrier recovery with
an on-chip PLL circuit. Samples and production quantities
are available now. See the Front-End
Tuner Solution Press Release from Sony Electronics.
Sony also announced the CXD1961AQ which includes a QPSK
demodulator, automatic clock recovery, MPEG-2 frame
synchronization, a Viterbi decoder, de-interleaver,
Reed-Solomon decoder, energy dispersal descrambler and
channel error monitoring. See the Singtle
Chip Solution for Satellite Receivers and Set-Top Boxes
Press Release.
The last chip may be of interest on the transmission
side. It is a real-time MPEG-2 video encoder with motion
estimation. The CXD1922Q supports MPEG MP@ML and SP@ML at
720x480 at 30 fps for NTSC. More information is available
in the Real-Time
MPEG-2 Encoder Press Release.
- SCIENCE - Scientists Propose Economical Alternative to
Tokamak Fusion Reactors (Nov. 20)
- Scientists have long viewed nuclear fusion as a solution
to the global energy crisis. However, there has been
little success demonstrating this techology and many
scientists doubt the International Thermonuclear
Experimental Reactor (ITER), based on the Tokamak design.
The Tokamak reactors use deuterium and tritium as fuel.
Researchers at the University of California, Irvine (UCI)
and the University of Florida say they have developed a
fusion reactor that uses a cheap, available fuel and
produces no more radioactivity than that from a
coal-fired power plant.
UCI physic professor Norman Rostoker, UCI research
physicist Michl Binderbauer and University of Florida
physic professor Hendrik Monkhorst published their work
in the November 21 issue of Science. A Press
Release from UCI said they "...propose a
colliding beam fusion reactor that would be fueled by
protons and boron, rather than the deuterium-tritium mix
that would power ITER. The reactor they have designed, on
paper, would produce a very small fraction of the
radioactivity of ITER, in turn allowing the facility to
be much smaller, easier to maintain and environmentally
safe."
The Release said the team plans to develop a commercial
reactor over the next 10 years with money from private
investors. Their work differs from other work in that it
focused on reactor design questions rather than fusion
experiments. More information is available in the UCI
Press Release.
- OTHER Items of Interest
-
- DIGITAL TELEVISION STATION APPLICATIONS - New feature!
- WCBS-DT Channel 56 - New York,
NY - 349 kW - Harris TAD-16UDAUP-4/32 antenna -
see ap971124.txt
November 17 - Issue 95 Final
Edition
- DTV - LG Semicon Announces Chipset for DTV Receivers
(Nov. 17)
- LG Semicon today announced "the world's first
Digital TV (DTV) chipset, designed by its sister company
LG Electronics." Paul A. Snopko, Zenith's director
of research and development, said "The first cut of
the LGS VSB solution, which replaced a rack of equipment
with a seven-inch circuit board earlier this year,
already met most of our specifications for the ATSC
transmission standard. Current samples are meeting or
exceeding our expectations for chips we plan to use in
our first HDTV products planned for introduction next
year."
The LG VSS ("Vestigial sideband Super Star")
chipset consists of five chips from LG plus one from
Sanyo: A VSB Sync/EQ (GDC21D001) which performs sync
recovery, equalization, and phase correction, a VSB
channel decoder (GDC21D002) which performs the decoding
of incoming data from the transmitter in 8VSB mode or
cable in the 16VSB mode using a Viterbi decoder and
RS-Decoder, a KA7785M I/Fdemodulator from Sanyo, a
one-chip MPEG2 video decoder (GDC21D401), a transport
chip (GDC21D301) for demultiplexing transport streams and
finally a video display processor (GDC21D701) which
receives all the ATSC image formats, including high
definition and standard-definition, and converts them
into a 1080 x 1920 interlaced high definition display
format. Samples of all but the last chip are available
now. The display processor will be available in first
quarter 1998.
- DIGITAL - Wireless Data Services Announce New Products
for Mobile Users (Nov. 17)
- With COMDEX underway in Las Vegas, a number of new
wireless communcations products have been announced.
AirMediaTM announced a mobile Internet antenna
for use with notebook computers and handheld devices. The
4.5 ounce device measures 3.73 inches by 2.68 inches by
0.83 inches. It can be powered off the portable
computer's serial port or from its own internal
batteries. It includes on-board storage so incoming news
and messages can be stored even if the computer is turned
off. For one of AirMedia's services see the next story.
An AirMedia
Press Release has more details on the unit, including
pricing.
The AirMedia device is receive-only. If you need two-way
access from your portable, you may be interested in the
Wireless Access AccessLink two-way data messaging pager,
which works with the 3-COM PalmPilot palmtop computer.
According to the Glenayre, Wireless Access' parent
company, this system uses SkyTel's 2-Way network to
provide users with the ability to send and receive
messages between Internet email addresses and access
third party Internet information services, all from the
PalmPilot. The belt-top AccessLink message pager connects
to the PalmPilot using a cable from JP Systems, Inc. The
Press Release on this product was not available when this
article was written but it may appear later on the Glenayre
News Page. (Disclosure: At the time this was written
I owned Glenayre common stock.)
- TV - KLAS Provides Las Vegas City Content to AirMediaTM
Wireless News Service (Nov. 17)
- AirMedia and CBS affiliate KLAS-TV, Las Vegas, announced
today they will join together to create the KLAS
Interactive Wireless Internet Broadcast Channel. This
channel will allow KLAS to "broadcast condensed
versions of its coverage of breaking Las Vegas news,
traffic reports, business developments and other
local-interest information directly to a viewer's home or
office PC's in real-time." John Hart, AirMedia's
Online Sales Manager said "AirMedia has developed
this narrowcast platform so local TV stations can attract
a captive audience: the office and home-office desktop
conputer user. We plan to bring this city channel model
to the top 20 TV markets, so that viewers can follow
breaking local and national news, weather and sports
throughout the day."
AirMedia does not use the broadcast station's facilities
for transmission. Instead, it relies on a narrowband 900
MHz. frequency, similar to that used for alphanumeric
paging. A Press
Release link outlining the KLAS service returned an
error message when this story was written. It may be
fixed by now. AirMedia's web site is at https://www.airmedia.com.
- SATELLITE - Spacenet 3 Moves to New Orbital Position
(Nov. 13)
- GE
Americom's Spacenet 3 is now in service at 83 degrees
west longitude. It had previously been located at 87
degrees west longitude. GE-3 is now in the 87 degree W.
position. Spacenet 3 has 14 C-band transponders and 1
Ku-band transponder available for service.
- SATELLITE - GE Americom's First European Satellite
Launched Successfully (Nov. 13)
- GE American
Communications announced it successfully launched its
GE-1E/Sirius 2 satellite from Kourou, French Guiana
yesterday on an Arianespace 4 rocket. GE Americom will
provide 16 high-power Ku transponders for use in the Pan
European market and NSAB will provide Sirius 2 service on
an additional 16 transponders to the Nordic Market. The
satellite will be positioned at 5 degrees east when it
becomes operational at the end of the year.
- DTV - Lucent Technologies Launches First DTV Receiver
Chip for U.S. Market (Nov. 12)
- Lucent Technologies' Microelectronics Group joins the
parade of companies offering chips for the U.S. DTV
market. Lucent today announced its AV8100, "a
complete system on a chip that can receive terrestrial
broadcasts of high definition television (HDTV),
multichannel standard definition television (SDTV), and
broadcast data. Lucent claimed "it is the first
commercially-available single-chip vestigial side-band
(VSB) receiver compliant with the Advanced Television
Systems Committee (ATSC) standard."
The AV8100 is being tested with Mitsubishi's RF tuner
system, video-audio decoder and display processor
components. Volume production of the AV8100 will begin in
the second quarter of 1998. Commercial samples should be
available early in 1998. The chip is packaged in a
160-pin, plastic quad flat pack and uses 3.3 volt CMOS
process technology.
More information on Lucent's semiconductors for consumer
electronics can be found at https://www.lucent.com/micro/concom.html.
The AV8100 data was not on this site when this issue was
published, but it should appear later. Additional
information is available in the Lucent
Press Release.
- DTV - 1998 CES will Showcase Product and Plans for
HDTV Sales (Nov. 11)
- In a Press Release issued today, the Consumer Electronics
Manufacturers Association (CEMA) announced that
"Virtually every major television manufacturer will
exhibit consumer HDTVs for the very first time and
announce pricing and delivery plans for the retail market
for the 1998 Holiday selling season." KLAS-TV will
be broadcasting HDTV in Las Vegas during the show.
CES has added an interesting array of sessions at the
show, including presentations by Joel Brinkley of the NY
Times; Philip Farmer, chairman, president and CEO of
Harris Corporation; James Meyer, CEO and executive VP of
Thomson Consumer Electronics, Craig Mundie, Microsoft; an
unidentified senior executive from CBS; Gary Chapman, CEO
of LIN Television Coproration; Frank Gardner, Sr. VP,
Broadcasting, Scripps Howard Broadcasting; Jim Keelor,
president, Cosmos Broadcasting Corp. and Chairman of
MSTV; a senior representative from Sony Electronics,
Inc.; and many others.
More details are available in the Press
Release or at https://www.cesweb.org.
Note that this web site requires a recent browser with
Java or ActiveX enabled. If you don't have such a browser
or prefer to keep some Java shut off for security, you
may have better luck (and faster response) going directly
to https://www.cesweb.org/mainpage/index.cfm.
Also see 1998
International CES Brings the Digital Frontier to Las
Vegas (Nov. 5) and Engineers
to See and Hear About the Latest Technologies at the 1998
International CES and Digital Engineering Conference
(Nov. 5). I didn't have a chance to include those in
last week's RF Current.
- SATELLITE - Globalstar Reschedules First Launch (Nov.
11)
- Globalstar, L.P. said it had rescheduled the launch of
its first four satellites. These are part of a Low Earth
Orbiting (LEO) system that will eventually consist of 56
satellites, the last of which will be launched in early
1999. Bernard L. Schwartz, chairman and CEO of Globalstar
said, "The postponement was adopted in order to
assure an adequate period of time to complete testing of
Globalstar's TT&C function prior to the initial
launch and was not related to any segment performance
issues. All other elements of the project... remain on
schedule and meet or exceed critical performance
criteria.
Commercial service is scheduled to begin no later than
the first quarter of 1999. Four terrestrial gateways are
already completed and construction on the remaining 34
continues on schedule. Globalstar is led by Loral Space
& Communications in partnership with QUALCOMM
Incorporated, AirTouch Communications, Alcatel, Alenia,
DACOM, Daimler-Benz Aerospace, France Telecom, Hyundai,
and others. More details are available in the Loral
Press Release.
- SCIENCE - Scientists Create Molecular Antenna to
Harvest Light (Nov. 11)
- Scientists at the University of Michigan and the
University of Illinois at Urbana-Champaign have developed
a new class of large demdrimer supermolecules which could
be using for generating electricity or as microscopic
optical sensors that change color when exposed to trace
amounts of chemicals. Dr. Raoul Kopelman, Professor of
Chemistry, Physics and Applied Physics at U-M, said
"Normally, light energy disperses randomly
throughout a molecule. But these molecules have a
specific tree-like structure which allows them to funnel
light energy through the branches and direct it to a
central point."
For more information on the physics behind this device,
including descriptions of "nanostars" and
excitons and a color diagram of the molecule, see the Universtiy
of Michigan News Release.
- OTHER Items of Interest
-
- DIGITAL TELEVISION STATION APPLICATIONS - New feature!
- KDFW-DT Channel 35 - Dallas TX -
857 kW - Andrew ATW22H4ESC1-35S - see ap971117.txt
- WXYZ-DT Channel 41 - Detroit MI
- 465 kW - Dielectric TFU-30DSC-RO3 - see ap971113.txt
November 10 - Issue 94 Final
Edition
- DTV - Sarnoff and Motorola Joint Initiative Targets
Cost-Effective DTV Chipset (Nov. 10)
- Motorola and Sarnoff today announced a joint initiative
to provide chipsets for DTV. Three of the
"semiconductor solutions" are already in
development. One is a digital Standard Definition TV
(SDTV) chipset for "affordable,. entry-level
television sets providing digital display quality and a
movie style aspect ratio." A converter-box chipset
solution is also being developed. A separate HDTV
Q&A from Sarnoff said "we believe the market
consensus price of $150 for a set-top box is
realistic." The third chipset is a
"functionally robust solution for HDTV sets
delivering five times the picture resolution of
SDTV." All the chipsets will include six channel
DolbyTM Surround Sound.
The press
release said development boards for the SDTV chipset
solutions will be available in the first quarter of 1998.
The HDTV chipset is targeted for the fourth quarter of
1998. The two companies plan to offer data capabilities
such as Web surfing, electronic shopping and video
conferencing for TV sets.
- TECHNOLOGY - Bell Labs Web Site Celebrates 50th
Anniversary of the Transistor (Nov. 5)
- Bell Laboratories today announced the launch of its LIVES-ON (Lucent
Innovation's Virtual Experience for Students on the Net)
web site celebrating the 50th anniversary of the
invention of the transistor. A Lucent
Press Release said "The LIVES-ON tour
guides visitors to museums across the globe to explore
the history and innovative uses of the transistor."
-
- TECHNOLOGY - NASA Solar-Powered Aircraft Begins
Science Mission in Hawaii (Nov. 4)
- NASA has begun flying "Pathfinder", its
solar-powered, remotely piloted aircraft, on the island
of Kauai. NASA chose the Barking Sands, Kauai Pacific
Missile Range because of "available airspace and
radio frequency". High levels of solar irradiance
also entered into the the decision.
Pathfinder has a wing span of 99 feet. Solar panels on
the upper wing surface can provide as much as 7,200 watts
of power for the craft's six electric motors and
six-million pixel digital camera. While the flights in
Hawaii will be conducted between 22,000 and 49,000 feet,
Pathfinder is capable of flying at altitudes over 71,500
feet.
More information on this interesting aircraft is
available in the NASA
Press Release.
- OTHER Items of Interest
-
November 3 - Issue 93 Final
Edition
- DTV - ATSC Begins Standards Work on DTV Satellite
Formats and Application Software (Nov. 3)
- The ATSC has begun work on defining the parameters for a
voluntary ATSC standard for satellite transmission of DTV
signals. The goal of this work is to make it possible for
service providers to share signal feeds and allow
manufacturers to build equipment for satellite DTV which
will be interoperable with equipment made by other
manufacturers.
The first step in this process is the ATSC
Satellite Transmission Request for Information,
available on the ATSC web site.
ATSC has started work to standardize DTV application
software. This is the software that will allow
interactive services such as stock-tickers, personalized
news, home shopping, commercials enhanced with product
information and web site addresses over broadcast DTV. A
paper by Aninda DasGupta of Phillips Research, Standardized
DTV Application Software, describes the need for a
standard run-time environment which guarantees that all
interactive applications authored by compliant service
provides will run on all ATSC-compliant receivers. The
document also suggests ways to achieve these
standardization goals.
More information on this project is available from the ATSC
DTV Application Software Environment Group web site.
- SATELLITE - Fractal Antenna Announces New Antennas for
Space Communications (Nov. 3)
- You are probably familiar with the concept of an
isotropic antenna. That is an antenna that radiates
equally well in all directions. This hypothetical antenna
is at the heart of many the formulas used in antenna
design. Now, imagine an actual antenna that duplicates
the point source properties of the isotropic radiator.
Fractal Antenna Systems, Inc., based in Fort Lauderdale,
Florida, says it has created such an antenna - the patent
pending 'isotropic FRACTENNAź'.
The company said the antenna provides a "very
simple, compact solution which matches well to 50 ohm
transmitter or transceiver systems and should prove a
robust performer." One use is on microsats, small,
inexpensive satellites which tumble in their orbit, with
no defined orientation. Company spokesman Phil Salkind
acknowledged that reflections from nearby objects destory
the symmetry when the antennas are used on the ground,
but he believed they would be useful in airborne
environments and perhaps in factory environments.
Fractal Antenna Systems also said it had a patent pending
on a 'fractalized helix' antenna. This antenna could be
used for highly directional antennas. Salkind explains
"the helix was known as a worse performer than a
dish of the same largest dimension. So the coils had to
be longer to equal the performance, making huge
corkscrews. The fractalized helix substantially shrinks
the size of the coil, now making it a practical
alternative. Imagine the foot and a half direct to
satellite dishes replaced by a far lower profile antenna
which fits inside the dimensions of a soda can."
Fractal Antenna Systems said the new designs will be
commercially available in early 1998. It will either
license the designs or commercially fabricate them. I
couldn't find a web site for the company, but I found an article
in PC Today that
talks about some of the work the company is doing and
explains how the antennas may be used in other
applications.
- TV - Oren and Rockwell Announce Chips for NTSC TV
Receivers (Nov. 3)
- You may remember my reports on Zoran's ghost cancelling
chip over a year ago. Oren Semiconductor has continued to
refine the chip and today announced its OR43200 ghost
cancellation chip, which includes internal DSP, a 576-tap
digial filter, video sync detection and a 10-bit D/A
converter. Oren said the chip has applications not only
in TV sets, but in PC-based TV tuner cards. The adaptive
equalization in the chip significantly lowers
bit-error-rates on data encoded in the TV vertical
blanking interval (VBI). Oren says the digital filter
technology in the chip is adaptable to HDTV. A
demonstration board is available from Oren for $750. An
earlier version of the chip was used in the Magnavox
ImageLockTM. My tests of this box showed that
it performed well when given a clean video input.
However, deep notches caused by severe ghosting tended to
increase the noise in the picture and in some cases
appeared to shift the black level. Another problem was
that the instructions with the box suggested it be hooked
to a VCR to obtain a baseband video input signal..
Unfortunately, if you followed this advice, the E-E video
from most consumer VCR's added significant frequency
response and group delay distortion, which hid any
benefit the box could provide. The real application of
this chip will be inside TV sets or tuners.
Rockwell's Fusion family of chips doesn't do ghost
cancellation. They do, however, provide broadcast media
technology for applications such as videoconferencing,
video email, video and still editing, stereo PC TV and
radio and data services. The devices are designed to
connected directly to a PC's PCI bus. Full information on
this chip set, including information on an evaluation
board, is available at https://www.brooktree.com/techinfo/infotainment/PCI_Decoder/index.html.
- FCC Adopts Report And Order on 39 GHz. Band - ET
Docket 95-183 (Nov. 3)
- In a previous RF Current I reported on Sky Station
International's bid for frequencies in the 39 GHz.
band for a stratospheric communications systems based on
floating communcations platforms high above major
population centers. In its Second
Report And Order on ET Docket 95-183, the FCC appears
to have adopted a much more conservative approach. While
it will allow point to multipoint transmissions in the 39
GHz. band, it will auction the spectrum by BTA (basic
trading area). The FCC said repacking exisitng 39 GHz.
terrestrial licensees to accommodate new satellite
operations would be difficult and it would not, at this
time, change the spectrum designation to allow satellite
services only.
Refer to the Second
Report And Order for more information, including
technical requirements and permissible operations.
- DTV - Sharp and Oregon Public Broadcasting Test Real
World HDTV (Oct. 30)
- One of the questions surrounding DTV is how well it will
work in the real world. Sharp Laboratories is working
with Oregon Public Broadcasting to find the answer to
this question. A press release issued today announced
they "have begun the first in a series of tests to
evaluate the real world transmission and reception of
HDTV video, audio and data signals using the new digital
broadcast spectrum." The tests began October 11th.
Gary Feather, business development manager for Digital
Video, Sharp Labs of America said "DTV is about
theater quality sound, data retrieval, interactivity,
entertainment and education. By conducting these real
world tests, Sharp will be able to develop products that
provide the best images and sound and exploit these
advanced services when they become available."
- OTHER Items of Interest
-
Other Issues Available:
1998
1997
1995 and 1996
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Last modified November 27, 1997 by Doug Lung dlung@transmitter.com
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