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NTIA Ex Parte Letter regarding the definition of "over-the-air signal of grade B intensity" for purposes of the Satellite Home Viewer Act

Docket Number
CS Docket No. 98-201, RM No. 9335, RM No. 9345

January 29, 1999

The Honorable William Kennard
Federal Communications Commission
The Portals
445 Twelfth Street, S.W.
Washington, D.C. 20554

RE: Ex Parte Letter in Satellite Delivery of Network Signals to Unserved Households for Purposes of the Satellite Home Viewer Act, Part 73 Definition and Measurement of Signals of Grade B Intensity, CS Docket No. 98-201, RM No. 9335, RM No. 9345

Dear Chairman Kennard:

I am writing today to applaud the Commission for expeditiously undertaking a rulemaking to define "over-the-air signal of grade B intensity" for purposes of the Satellite Home Viewer Act.(1) It is my hope that the federal courts(2) will benefit from the Commission's guidance on this important issue.

As noted in my September 4, 1998, letter to you, the definition of "signal of grade B intensity" is key to whether many consumers will have real choice of programming providers.

This Administration has strongly supported the development of robust competition in the multichannel video programming marketplace as the way to bring greater viewing choices, lower prices and better services to consumers.

The Institute for Telecommunication Sciences (ITS) of the National Telecommunications and Information Administration has provided sample data on the number of households that could be affected by the various prediction methods under consideration by the Commission.(3) ITS took a sample of one network affiliate station from 16 Neilsen Media Research Designated Market Areas (DMAs) ranked by number of households. This sample reflects significant geographic diversity, communities of various sizes, UHF and VHF stations with varying channel numbers, and equal numbers of affiliates of each of the four networks. (4) ITS maps plotting the results of this sample graphically reveal the variations in the number of affected households of selection by using the prediction methods: FCC F (50,50) Field Strength Charts (47 C.F.R. § 73.699 Figures 9 and 10), Longley-Rice ITM,(5) and TIREM Version 3.(6) Maps for the sampled stations are available at

While NTIA takes no position on the specific definition that the Commission should adopt, we urge the Commission to adopt a definition and measurement that will best promote competition and consumer choice.

Thank you for your consideration of these views.


Larry Irving


cc: The Honorable Susan Ness
The Honorable Harold Furchtgott-Roth
The Honorable Michael Powell
The Honorable Gloria Tristani
Deborah A. Lathen, Chief, Cable Services Bureau


1. Satellite Home Viewer Act of 1994, Pub. L. No. 103-369, 108 Stat. 3477 (1994) (codified at 17 U.S.C. § 119).

2. See CBS Inc., et al. v. PrimeTime 24 Joint Venture, Case No. 96-3650-CIV-NESBITT (S.D. Fla. July 10, 1998); ABC Inc. v. PrimeTime 24 Joint Venture, Case No. Civ. A. 1:97CV00090 (M.D. N.C. July 16, 1998).

3. A number of commenters in this proceeding supported the adoption of TIREM (Terrain Integrated Rough Earth Model) for predicting unserved households. The original version of TIREM was developed by the Electromagnetic Compatability Analysis Center (ECAC) within the Department of Defense in the 1960s and has continued to be modified by that organization. ECAC's name was recently changed to the Joint Spectrum Center (JSC).

4. For a summary of this data, see the attached table entitled "Network Affiliate Sample from 16 DMAs."

5. Longley-Rice ITM (Irregular Terrain Model, Version 1.2.2) is available to the public from an NTIA web site at The files at this site include source code and model description.

6. TIREM Version 3 is available to the public from an NTIA web site at The files at this site include the source and executable code and a 30-arc second topographic database (i.e., the database contains the terrain elevations in height above mean sea level for every 30 arc-seconds of latitute and longitude fo rthe earth's surface). This version is approximately 20 years old and was developed by ECAC/JSC. For purposes of this sample, ITS modified TIREM Version 3 to permit access to the 3-second topographic database commonly used for broadcast studies. TIREM Version 4 is the latest version of the model also developed and maintained by the JSC. This model improves on the 20 year-old coding used in Version 3 but fundamentally uses the same technical algorithms and yields similar but not identical results as Version 3. This version of the model, however, has limited distribution with export restrictions under the Arms Control Act (22 U.S.C. § 2751 et seq.) or Executive Order 12460. While NTIA is a Federal agency eligible to receive TIREM source code, other organizations may not be eligible to receive TIREM Version 4 source or executable code without explicit permission from JSC.