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This page contains stories from RF Current issues published in
February 1999. Links referenced in the articles were current when
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February 22, 1999 - Issue 154 Final Edition
- FCC International Bureau Announces IBFS Demonstration (Feb. 22)
- The FCC's International Bureau has enabled public Internet access to its IBFS system. The system allows users to download various reports on satellite stations (both on the ground and in orbit) and international HF broadcast and public fixed radio stations. It may also be used for on-line reporting and electronic filing after registration. Visit the FCC IBFS page to download a User's Manual and access other IBFS features.
The International Bureau will hold IBFS demonstration and training sessions on March 2, 1999 in Washington D.C. If you are interested in attending one of these sessions refer to the Public Notice (pnin9038) for more information.
- DTV - DiviCom Introduces HDTV Encoder (Feb. 22)
- In a Press Release issued today, Divicom announced its first high definition encoder. Divicom is a wholly-owned subsidiary of C-Cube Microsystems, a leading digital video compression chip manufacturer. Divicom's MV400 HD encoder uses the latest version of C-Cube's DVxpert™ chip, allowing it to provide encoding for 1080i, 720p and 480p ATSC, DVB and ISDB formats in a one rack unit (1.75 inches) high enclosure.
Divicom said its MotionTrack™ feature and hardware architecture result in "better video quality with less effort." The MV400 contains multiple DVxpert encoding chips linked with a high speed bus in a single module. More information is available on the Divicom web site.
- CHIPS - TDK and Kenwood Develop Receiver Sub-System for Mobile Satellite Broadcasting (Feb. 18)
- TDK Semiconductor and Kenwood Corporation are working together to develop the first receiver subsystem for the MSB (mobile satellite broadcasting) system. This system uses satellite and terrestrial transmitters to send CD-quality radio, still images, simple moving pictures, traffic and weather information, music and news to mobile receivers.
The system operates in the 2.6 GHz band. Introduction in Japan is planned in 2001. The system uses two antenna modules for diversity reception. Each module has a microstrip antenna and a low noise amplifier (LNA). These are connected to an RF module, which down-converts the signal to provide two channels of analog I/Q output. For details, refer to the TDK Press Release.
- NASA's IMAGE camera will take pictures of Earth's magnetic shield (Feb. 16)
- Ham radio operators and other users of the HF spectrum "see" the effect events in the Earth's magnetosphere can have on radio communications. Satellite operators are concerned about the impact on delicate electronics in their spacecraft. Solar-terrestrial effects in this region have been associated with massive power outages and even corrosion of long-distance pipelines. If NASA is successful in launching and deploying its IMAGE spacecraft, these operators and others with Internet access will be able to view images of light emitted by neutral atoms, radio echoes, extreme ultraviolet and far ultraviolet from the magnetosphere.
NASA/Marshall co-investigator Dr. Dennis Gallagher said "This is going to be an open data set. Our ambition is that from the first data set that comes to the ground, starting about a month after launch, there will be browse data on the worldwide web for anyone to look at." Data on the IMAGE camera, its orbit, background information on the magnetosphere and links for further research can be found in the February 16 NASA Science News.
- DIGITAL TELEVISION STATION ACTIONS - See ac990217.txt
for more information
||KITV Argyle Television
||License to cover CP
||Grapevine of Savannah
||Dielectric TFU-24GTH 04
||Dielectric TFU-26GTH-R 04
- OTHER Items of Interest
February 15, 1999 - Issue 153 Final Edition
- DTV - NDS Plans Launch of Digital Electronic News Gathering at NAB (Feb. 11)
- NDS has developed a Digital Electronic News Gathering (DENG) system using COFDM modulation. Noel Matthews, new business development manager of NDS Broadcast, said "Clearly MPEG-2 digital transmissions can provide more efficient transmission of video but when used with a single carrier modulation scheme, such as QPSK or QAM, it is no more robust than analogue in bad multipath conditions. With our vast experience of using OFDM multi-carrier technology for digital terrestrial TV, we have now invented a new approach to give broadcasters a reliable solution for news and sport coverage from mobile OB units in difficult locations."
NDS' DENG has been tested in ENG van trials in Dublin, Melbourne and Chicago. Matthews said the tests proved "the system can deliver pictures without the need for tall masts and aerials from sites previously unuseable."
More information on DENG is available in the NDS Press Release. For information on NDS' NAB plans, see the release KNDS live TV show on the NDS NAB stand demonstrates leading TV digital broadcast technologies.
- FCC Changes Cut-Off Date for Co-Primary Status for Some 18 GHz Operations (Feb. 10)
- The FCC, in its Notice of Proposed Rukemaking (NPRM) on redesignation of the 18 GHz frequency band to allocate additional spectrum for Broadcast Satellite use, proposed that fixed-service (FS) applications in the 18 GHz band filed after the release of the NPRM be given secondary status for fixed satellite service operations if the FCC adopted the proposals reallocating the spectrum for satellite use.
The secondary status proposal was opposed in filing by the Telecommunications Industry Association and the Independent Cable and Telecommunications Association. After considering its decision, the FCC ordered that "the proposed cut-off date for co-primary status for new FS authorizations in the 18.3-18.55 GHz band is changed, as it applies to private cable operators, ... to the date of the release of the future Report and Order in this proceeding."
The FCC did not change the proposed cut-off date for other terrestrial fixed operations in the 18.3-18.55 GHz and 18.8-19.3 GHz bands. Please read the full text of the FCC Order (fcc99018) for more details on this decision.
- Satellite - Globalstar succesfully launches four LEO satellites (Feb. 9)
- Globalstar said it successfully launched four low-earth-orbiting (LEO) satellite into space from the Baikonur Cosmodrome in Kazakhstan aboard a Soyuz-Ikar launch vehicle. Globalstar engineering teams will raise the satellites to an operational altitude of 1,414 kilometers.
These four satellites will join eight Globalstar satellite already in orbit. Globalstar plans to start commercial service in the third quarter of 1999 with at least 32 satellites in orbit, eventually increasing this to 52 satellites by the end of 1999. The Globalstar system "will provide people around the world fixed-phone and hand-held mobile satellite phone services, as well as data transmission (at up to 9.6 kilobits per second), messaging, facsimile and position location services." See the Loral Globalstar Press Release for details.
- DIGITAL TELEVISION STATION APPLICATIONS - See ac990211.txt
for more information
||Rocky Mountain PTV
- DIGITAL TELEVISION STATION ACTIONS - See ac990209.txt
for more information
||Dielectric TFU-30DSC-R C170
||Shively 2200 Super-Turnstile
- OTHER Items of Interest
February 8, 1999 - Issue 152 Final Edition
- FCC Proposes Establishment of DTV Industry Coordination Committee (Feb. 4)
- In a detailed Notice of Proposed Rule Making, the FCC said "We therefore believe it is desirable to consider the industry's suggestion for a private
industry coordination committee system that would assist the Commission in matters relating to
managing the DTV transition. As suggested by the Broadcasters' Caucus, we believe the general
principles and policies that were applied in establishing rules for frequency coordination in the
land mobile services are also relevant and appropriate for guiding the development of an industry
coordination committee system for broadcast television."
In the NPRM, the FCC outlined the services Congress allowed it to assign to industry frequency coordinators:
- Provide coordination services on a non-discriminatory basis, including charges for services rendered.
- Perform the coordination function by:
- 1) checking applications for completeness, accuracy and compliance with the applicable FCC rules;
- 2) identifying the most appropriate frequency (requests for specific frequencies were to be accompanied by a technical showing);
- 3) sending the application and recommendation to the FCC.
- Process applications in order of receipt even if this does not lead to actions in the same order.
- Forward a recommendation to the Commission within 20 work days of the receipt of an application (speed of service requirement).
- Assist in resolution of post-licensing conflicts.
- Handle inter-service sharing requests.
- Provide services on a reasonable cost-based fee schedule.
- Facilitate the introduction of new services.
- Provide a single nationwide point of contact with the Commission.
The FCC also outlined addtional activities where broadcast coordinators could aid the implementation of DTV service:
- Coordination of station and allotment additions/changes with land mobile licensees operating on frequencies in the TV bands and on frequencies in adjacent bands to avoid interference.
- Coordination of station and allotment additions/changes on channel 6, at 82-88 MHz, with noncommercial FM radio stations in the reserved band, at 88-92 MHz, to avoid interference.
- Assist in identifying and resolving any other issues or problems that might arise with regard to a proposal, such as proximity of television operations to AM radio towers and operation in radio Quiet Zones.
- Coordination of requests for television special temporary authorizations (STAs) and requests for experimental authorizations under the television service.
- Coordination of the use of broadcast auxiliary frequencies among TV stations.
- Coordination of low power TV and TV translator station additions/changes, including assisting low power television and TV translator stations affected by DTV implementation. For example, the coordinators could aid low power operators in developing changes in their operations to avoid causing interference to DTV stations or, where necessary, to identify replacement channels.
- Coordination among antenna site users to ensure that such sites comply with the rules for exposure of humans to radio frequency radiation set forth in Sections 1.1301-1319 of the rules.
- For stations on channels 60-69, identification of channels in the DTV core spectrum, i.e. channels 2-51, for relocation prior to the end of the transition.
The FCC requested comment "on whether we should require television station applicants, construction permit holders, licensees and others with proposals that would affect TV spectrum to coordinate their proposals through the industry committee process or simply to make participation in that process voluntary." It also said that it did not want consideration of this issue to delay implementation of DTV service. The FCC stated "we advise broadcasters that we will continue to process applications for DTV stations and requests for modification of facilities during the course of this proceeding. Broadcasters preparing DTV applications and or station modification requests therefore should not delay the filing of those applications."
This is an important issue affecting most TV broadcasters in one way or another. Who will sit on the committee that will act on DTV applications? How much will they be paid? Will this be a full time job or will they continue to be paid by their employer, TV network, station group, consulting firm or industry group? How will this affect their decision on issues? Will there be a built-in bias against smaller TV stations and LPTV stations not represented by the larger organizations? Comments are due at the FCC March 29, 1999. Reply comments are due April 28, 1999. The full text of the Notice of Proposed Rulemaking is available for downloading: fcc99008.txt (text format) and fcc99008.wp (WordPerfect format).
- DTV - Lucent Proposes DTV Closed-Captioning Spec to ATSC (Feb. 4)
- Lucent Digital Video announced it "will propose the first closed-captioning specification for digital television (DTV) to the Advanced Television Systems Committee (ATSC) for standardization." The specification covers the interface between an EIA-708 caption server and MPEG-2 encoders. ULTECH Corporation and DiviCom are cooperating with Lucent in submitting the specification.
Under the "Proposed EIA-708 Caption Server to Encoder Interface Specification", the caption data server devices will provide partially formated EIA-708-A data to ATSC video encoders over the Lucent designed interface. Formatting is completed in the video encoder, which places the data into the picture-level user data field.
More information can be found in the Lucent Digital Video Press Release. Harris Corporation demonstrated the ULTECH DTV-708 Closed Caption Data Server and Harris Flexicoder™ ATSC MPEG encoding system at the Model Station, WHD, in Washington D.C. See the Harris Corporation Press Release.
- FCC Adopts Longley-Rice Model for Predicting Signal Intensity for SHVA Purposes (Feb. 2)
- The FCC has adopted a methodology for measuring signal strength at an individual household for purposes of determining whether the household is "unserved" by network TV broadcast stations and therefore eligible, under the Satellite Home Viewer Act (SHVA) to receive the network's programming on a home satellite dish. The FCC rejected requests to redefine the field strength required for a Grade B signal level. For purposes of determing SHVA eligibility, it did, however, change its methods both for measuring signal level and predicting the received signal level at a given location.
For signal level measurements, requirements include:
- Making at least five measurements in a cluster as close as possible to the location being tested.
- Using a tuned half-wave dipole as the testing antenna.
- Locating the measurements in a cluster as close as possible to a reasonable and likely spot for the receiving antenna.
For predicting signal levels, the FCC adopted the "Individual Location Longley-Rice" or "ILLR" model. This is similar to the model used for determining DTV allocations, population served and interference. The FCC Order said "This model is an accurate, practical, and readily available model for determining signal intensity at individual locations." Model parameters are different than those specified in OET-69 for DTV operation. Specifically:
- the model is run in individual mode;
- terrain elevation (e.g., hills and valleys) is considered every 1/10 of a kilometer;
- receiving antenna height is assumed to be 20 feet above ground for one-story buildings and 30 feet above ground for buildings taller than one-story;
- the confidence variability factor is 50%;
- where error codes appear in the model's predictions, they shall be ignored and the predicted value accepted or the result shall be tested with an on-site measurement;
- land use and land cover (e.g., vegetation and buildings) shall be included when an accurate method for doing so is developed;
"The Commission believes the ILLR can be used for predicting signal strength for purposes of the SHVA as well as for other purposes that require information about signal intensity at discrete locations." However, it continued, "The model would not supplant currently-existing approaches for depicting a field strength contour or for describing a station's service area."
For more details on this decision, including legal issues such as who pays for these studies, download the full text of the Order - fcc99014.txt (text) or fcc99014.wp (WordPerfect). A short summary is available in the Cable Services Bureau News Release (nrcb9001). Longley-Rice 1.2.2 Fortran code may be downloaded from the NTIA/ITS FTP site.
- SCIENCE - NewScientist article reports NASA studying Gravity Shield (Feb. 2)
- The latest issue of NewScientist contains an article by Charles Seife titled Escape from Earth. It reported that NASA awarded a grant to a project to study gravity shields, which most scientists think are impossible. If the link above does not take you to the story, try a search from the NewScientist Home Page. It makes interesting reading.
The story contained a link to a government site with a copy of a report by E. E. Podkletnov at the Moscow Chemical Scientific Research Centre. The report noted that an RF electromagnetic field was used to induce currents in superconducting ceramics, which caused the disk to raise and rotate. Samples made of metals, plastic, ceramic, wood and other materials were situated above the disk and their weight was measured. The report said "All the samples showed the same partial loss of weight, no matter what material they were made of." The maximum shielding effect was slightly more than 2 percent with a magnetic field operating between 3.2 and 3.8 MHz.
Science fiction or science fact? The entire report is available in most Unix friendly formats (including Adobe Acrobat) at http://xxx.lanl.gov/abs/cond-mat/9701074.
- OTHER Items of Interest
February 1, 1999 - Issue 151 Final Edition
- FCC - GMDSS Replaces Morse Code on Big Ships (Feb. 1)
- Today, February 1, 1999, the Federal Communications Commission announced that the Global Maritime Distress and Safety System (GMDSS) is fully implemented in the United States. GMDSS is an automated system that uses both geostationary satellites and terrestrial digital communications to send and receive distress and safety communications world-wide. This system replaces the Morse Code radiotelegraph system and with it the need for ships to have a skilled radiotelegraph operator on-board when sailing in the open sea or on international voyages. [ ..._._ ]
- CHIPS - LSI Logic Introduces Satellite Set-Top Box Tuner Chip Set (Feb. 1)
- LSI Logic today announced the L64733/34 tuner and channel-receiver chip set. The chip set, which is capable of demodulating L-band DBS-compliant signals at data rates from 1 to 45 MBaud, can be mounted directly on a motherboard or in a small module.
The two-chip set does not require external IF or baseband filters. It consists of the L64733 zero-IF (also referred to as "direct conversion") tuner IC with an on-chip frequency synthesizer and the L64734 microcontroller for tuning, tracking and acquistion. A Direct Conversion Satellite Developer's Kit including printed circuit board layout information and demodulator driver software is available from NDS. Refer to the LSI Logic Press Release.
- FCC Grants Teledesic LLL Application for Modification of Space Station Authorization (Jan. 29)
- The FCC granted Teledesic's application to modify its system by
- 1) decreasing the number of satellites from 840 to 288;
- 2) increasing the altitude to the 1375-1394 km range;
- 3) decreasing the number of orbital planes to 12 and the number of satellites in each plane to 24;
- 4) decreasing the inclination of the orbital plans to 84 degrees;
- 5) adding emission designators; and
- 6) adding optical inter-satellite links.
More technical details, along with discussions of comments on the proposal are available in the Order And Authorization (da990267).
- INDUSTRY - Acrodyne Stockholders Approve Sinclair Broadcast Group Agreement (Jan. 28)
- On January 28th, Acrodyne Communications' stockholders approved the agreement with Sinclair Broadcast Group, Inc. Under the agreement, Sinclair acquired a significant equity position in Acrodyne and three positions on the Board of Directors, including Nat Ostroff as Chairman. Robert Mancuso, President and CEO of Acrodyne, said "We are pleased that this agreement won the overwhelming support of our shareholders. We believe that with this relationship with Sinclair, Acrodyne will have the financial and intellectual resources to become the premier supplier of both analog and digital equipment and services to the domestic television broadcast industry."
More information on this Agreement can be found in the Acrodyne Press Release and in the November 25, 1998 RF Current.
- DIGITAL - CEMA Files Comments with FCC on Terrestrial Digital Radio (Jan. 26)
- The Consumer Electronics Manufacturers Assocation (CEMA) in comments filed Monday urged the FCC to "implement the development of the most effective terrestrial digital audio radio (DAR) service, one that meets listeners' expectations in terms of sound quality and does not interfere with existing analog radio services or other digital services." CEMA did not endorse any particular DAR technology, but asked the FCC to:
- "Establish comprehensive technical assessments ot weight the performance of competing systems;
- "Ensure that DAR systems do not adversely affect existing analog radio services while providing high quality and robust digital coverage, and
- "Rely on laboratory tests and not just field testing to define DAR system performance.
See the CEMA Press Release or refer to the full text of CEMA's Reply Comments and Comments on the Petition for Rulemaking filed by USA Digital Radio.
- DTV - Konka And ATSC Demonstrate HDTV in Shenzhen China (Jan. 26)
- Konka Group and the Advanced Television Systems Committee (ATSC) conducted the first digital HDTV demonstrations in Shenzhen, China as part of the '99 Shenzhen International Digital Television Broadcasting Seminar. China is evaluating DTV systems for using in the country.
Professor Hui Yongzheng, Vice Minister of the Ministry of Science and Technology of the PRC said "We are delighted that Konka and the ATSC have staged these HDTV demonstrations as part of our symposium. The symposium and these demonstrations will promote the development and application of digital television technology in China. We are actively evaluating the ATSC Digital Television Standard, as well as other DTV approaches, and developing our own prototype DTV equipment, to determine the best course for China to pursue, and these demonstrations provide an important focal point for our deliberations."
Konka Group's Director General Manager, Chen Weirong, said "Konka has developed significant expertise in digital television technology, and we have announced plans to market our HDTV receivers in North America within a few months."
More information is available in an ATSC Press Release.
- DIGITAL TELEVISION STATION ACTIONS - See ac990129.txt
for more information
- OTHER Items of Interest
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