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.

Issues are dated each Monday, although recently I've needed an extra day or two to complete each issue. Articles may be posted earlier if time permits or if there is a major, breaking story.

<<< Back to March 20 - Issue 206

March 27, 2000 - Issue 207 Final Edition

SATELLITE - EchoStar to Offer Bundled Two-Way Broadband Internet, TV Service Via Satellte (Mar. 27)

EchoStar announced it has taken a 12 percent interest in iSky, formerly KaSTAR Satellite Communications. Together, the companies will offer consumers two-way wireless broadband Internet access via satellite, along with DISH Network(TM) satellite television channels. The 1.5 Mbps "always on" Internet service will use iSky's Ka-band satellites and is scheduled for launch in 2001. Consumers will require a 26 inch iSky/DISH Network dish to send and receive Internet data and access satellite TV programming.

iSky's first Ka-band band satellite is expected to be launched in the third-quarter of 2001. The Space Sytems/Loral satellite will be positioned at 109.2 degrees West Longitude. A second iSky satellite is planned for launch in mid-2002 to serve Latin America. Thomas Moore, president and CEO of iSky said "Our partnership with EchoStar is key to our strategy of aggressively targeting the consumer market. This will be the first easy and affordable way for consumers to access Ka-band satellite broadband and satellite TV through one sales process, one installation and one set of equipment. We forecast that 25 to 30 million U.S. homes will not have access to any other broadband solution when our service hits the market next year. Of those, we expect a significant number will choose iSKY."

The first iSky satellites will act as simple repeaters, using "bent pipe" technology. Later satellites may have on-board processing for increased flexibility and capacity. iSky has fixed-satellite service Ka-Band licenses at orbital locations of 73 degrees and 109.2 degrees West Longitude. It also holds an exclusive commercial license to the Ka-band capacity on the TeleSat ANIK F2 satellite at 111.1 degrees West Longitude.

More information on the service can be found at www.isky.net and in the EchoStar / iSky Press Release.

DTV - Sinclair President David Smith Comments on ATSC Task Force to Examine Problems with 8-VSB (Mar. 24)

In a letter to broadcasters dated March 24, David D. Smith, President of Sinclair Broadcast Group, Inc. urged broadcasters to participate in the new ATSC Task Force to examine problems with 8-VSB. The letter took note of comments by Robert Graves, Chairman of the ATSC and representatives from Zenith and Motorola at a panel discussion held March 21st in Los Angeles at the DTV-6 meeting. The comments praised Sinclair, for, as stated in the letter, "its efforts to bring the serious nature of the reception problems of 8-VSB to the attention of the industry." Mr. Graves announced the ATSC Executive Committee had authorized a special task force to investigate the problems with 8-VSB and advise the Executive Committee.

In the letter, David Smith said, "This is a new departure from the standard ATSC position and may represent the last best hope we have to reach a satisfactory solution in a short time. Sinclair was specifically invited to participate to the fullest extent possible. We intend to attend this first meeting. The organization of this Task Force and its agenda are critical to achieving anything meaningful quickly. It is an opportunity for broadcasters to regain some modest control of our future in DTV and to ensure that we are serious providers of digital services including entertainment and HDTV to all kinds of devices. "

David Smith ended the letter by saying, "While Sinclair is not endorsing the ATSC's position, we do believe that our joint efforts have gotten us to this moment and it is a moment worth pursuing. The outcome of the meeting of the Task Force will allow us to judge the sincerity of Mr. Graves and the ATSC to respond to the mounting evidence that the 8-VSB modulation system does not satisfy the vast majority of broadcasters' requirements."

FCC Criticizes NAB CD Showing Simulated Interference from Low Power FM Radio Stations (Mar. 24)

The FCC issued a Statement from Dale Hatfield, Chief of the Office of Engineering and Technology and Roy Stewart, Chief of the Mass Media Bureau, concerning low power FM engineering issues. The statement began, "We are concerned that Members of Congress have received misleading engineering information about alleged interference from low power FM radio stations. One particularly misleading disinformation effort involves a compact disc being distributed by NAB that purports to demonstrate the type of interference to existing radio stations that NAB claims will occur from new low power FM radio stations. This CD demonstration is misleading and is simply wrong."

The statement said the NAB CD was produced by artifically mixing two previously recorded radio signals and does not portray actual interference. It is not a demonstration of actual interference between two FM radio stations. The CD "interference" sounds like two distinct, clearly audible audio signals. The FCC pointed out that in cases of interference between stations on third adjacent channels, the interference would appear as noise or hissing. It said "The NAB 'crosstalk' demonstration simply does not represent actual FM radio performance and therefore is meaningless.

The FCC statement said the NAB had also incorrectly stated that the FCC considers a 3 percent level of total harmonic distortion plus noise from interference to be acceptable. The FCC Report and Order clearly indicated the Comission based interference evaluations on a 1 percent level. The statement said, "To continue to make the argument in this CD about the 3% level can only be viewed as a deliberate misrepresentation of the FCC's findings and analysis."

Concerns about the impact of low power FM on radio reading services, operating on FM subcarriers, was also addressed. The FCC said its testing showed existing stations "will not experience harmful interference". However, the FCC will continue to work with National Public Radio to test radio service receivers and, if necessary, will recommend "steps specifically tailored to deal with the radio reading service issue."

FCC Releases Notice of Inquiry Regarding Software Defined Radios (Mar. 21)

Refer to the March 20 RF Current for a summary of the FCC News Release on this Notice of Inquiry (NOI). The full text of the Notice of Inquiry was released March 21. In it, the FCC listed specific areas where it was seeking comment on the current state of software defined radio technology:

" What features in a radio are apt to be controlled by software? For example, could the operating frequency, output power, and modulation format be software controlled?
What are the specific limitations of current software defined radio technology? What are the cost implications?
What capabilities could software defined radios have that are not found in current radio technology?
When could software defined radios be deployed commercially, and for what services or purposes?
What work is being done on software defined radios internationally, and are there any steps the Commission should take to encourage this work?"

The NOI provided more detail on the regulatory aspects of software defined radio the FCC is seeking comment on:

"Should we approve the radio hardware, the software or the combination of them?
Are the currently required measurements in Part 2 of the rules appropriate for software defined radios?
How should software defined radio equipment be tested for compliance, including compliance with SAR requirements? What type of approval process and labeling would be appropriate?
Should we regulate who changes the software and the manner in which it is done? If so, should the Commission maintain records of such modifications?
What are the various means that may be used to download new software? We anticipate, for example, that software could be downloaded by methods such as direct connection to a programming device or over the airwaves. To what extent will the software interfaces be standardized?
Should we require anti-tampering or other security features? How would such security features work? Could equipment be designed to prevent it from transmitting in certain designated frequency bands, such as those allocated exclusively for government use, as a safeguard against causing interference?
Do we need to adopt additional requirements for software defined radios to ensure the privacy of users' communications?"

The FCC outlined a possible scenario for software defined radios:

"The software could be tested and approved to ensure that the transmitter meets the applicable technical requirements under all operating conditions. In order to ensure that untested and unapproved software could not be loaded, such transmitters would have an authentication system that checks the software for an authentication code added to it by the FCC or a Telecommunications Certification Body (TCB). The software itself would be submitted for approval in a process similar to today's application process except that a copy of the object code would be supplied in machine-readable form. Upon approving the software application, which would involve a test of the hardware and software together similar to today's tests, the FCC or TCB would compute the authentication code for the submitted source code and send it to the applicant. The authentication system would be a two key system in which the key needed to compute the authentication code would be known to only the FCC or TCB, and the key needed to check in a transmitter object code which is being loaded would be publicly available."

Other technical/regulatory questions addressed in the NOI include: How should simple changes to software be handled that do not affect the operating parameters of the equipment but require the computation of a new authentication code? Could an "authentication only" service be offered for them? Is there a need for a method to display information about the software loaded in a transmitter? If so, what method should be used and what information should be displayed?

The comment date will be 75 days from the publication of the NOI in the Federal Register, with reply comments due 30 days later. The full text of the Notice of Inquiry is available from the FCC as a Text file (fcc00103.txt) or a Word file (fcc00103.doc).

OTHER Items of Interest

FCC Lottery Determines Order for Accepting Applications for Low Power FM Radio Station Licenses - news release - first applications will be accepted from Alaska, California, D.C., Georgia, Indiana, Louisiana, Maine, Mariana Islands, Maryland, Oklahoma, Rhode Islands and Utah. Five day filing window to be announced at the end of April.
Andrew Improves Warranty On Television Broadcast RF Products - press release - minimum 3 year warranty on all Andrew broadcast products, up to ten years in some cases

>>>>Next April 3 - Issue 208

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