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Use of Radio Frequencies Above 40 GHz for New Radio Applications.

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Federal Communications Commision.


Final rule; denial.


This document denies the Petitions for Reconsideration filed by the National Radio Astronomy Observatory (“NRAO”) and New England Digital Distribution, Inc., (“NEDD”). These petitions requested reconsideration of the Commission's Third Report and Order (“third Order”) in this proceeding. This action reaffirms the previous Commission decisions on the spurious emission limit for unlicensed vehicular radar devices operating in the 76-77 GHz band, and the coordination channel and transmitter identification requirements contained in the spectrum etiquette for unlicensed operation in the 59-64 GHz band.

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Rodney Conway, Office of Engineering and Technology, (202) 418-2904.

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This is a summary of the Commission's Order, ET Docket 94-124, FCC 00-161, adopted May 8, 2000 and May 17, 2000. The full text of this Commission decision is available for inspection and copying during normal business hours in the FCC Reference Information Center, Room CY-A257, 445 12th Street, SW., Washington, DC, and also may be purchased from the Commission's duplication contractor, International Transcription Service, (202) 857-3800, 1231 20th Street, NW., Washington, DC 20036.

Summary of the Memorandum Opinion and Order

1. The NRAO filed a Petition for Reconsideration requesting a more stringent spurious emission limit of 2 pW/cm2 rather than the limit of 1000 pW/cm2 for vehicle radar systems operating in the 76-77 GHz band. NEDD filed a Petition for Reconsideration of the coordination channel and transmitter identification requirements of the spectrum etiquette for unlicensed operation in the 59-64 GHz band. These petitions requested reconsideration of the Commission's Third Report and Order (“Third Order”) in this proceeding, 63 FR 42276, August 7, 1998.

Emission Limits Above 200 GHz

2. The NRAO requests a more stringent spurious emission limit of 2 pW/cm2 as measured at three meters for unlicensed devices operating in the 76-77 GHz band. The NRAO petition provides no new information to support its request; it instead points to comments filed by the National Academy of Sciences Committee on Radio Frequencies (“CORF”) earlier in this proceeding as the basis for its request. NRAO alleges that, in the Third Order, the Commission did not adequately address the specific concerns or calculations set forth by CORF, nor did it explain the basis of its beliefs in rejecting CORF's proposed limits in favor of those recommended by the National Telecommunications and Information Administration (“NTIA”). NRAO believes that such a failure to address the key argument is arbitrary and capricious and does not constitute reasoned decision-making.

3. Our review reveals that CORF essentially assumes that the vehicular radars will be within boresight of or targeted at the radio astronomy receive antenna and be capable of radiating a coherent and focused emission directly into a 0 dBi side lobe of a radio astronomy antenna without taking into account any attenuation from the atmosphere, intervening terrain, angular separation or elevation separation that may be present. In addition, we note that IEEE Vehicular Radar Standards Start Printed Page 38432Subcommittee document VRS-96-6 states that radio astronomy observatories typically have control over access to a distance of one kilometer from the telescopes to provide protection from interference caused by automobile spark plugs and other uncontrolled RFI sources. It is unclear from reading the comments why CORF selected a distance of 250 meters as a distance beyond which radio astronomy operations are not able to restrict operation of RF devices. We are aware that the radio astronomy observatory at Kitt Peak, Arizona may have had a controlled distance of less than 1 kilometer due to the public access afforded the site. We also note that NRAO has announced that they will be closing the millimeter wave telescope at Kitt Peak on July 1, 2000. The record in this proceeding has not made us aware of any other radio astronomy observatories that offer similar essential public access. We note that the IEEE standard implies that radio astronomy observatories do have control of areas surrounding their receive antennas. As a result there may be interference mitigation procedures, such as erecting a fence, that could be utilized to further minimize the potential for receiving any interference from the vehicular radars. Given the limited number of radio astronomy observatories and the potential benefit of these unlicensed devices we encourage the radio astronomy community and the automobile industry to work together to develop interference mitigation procedures.

4. We have carefully considered NRAO's petition for reconsideration and related comments and determine that the public interest will be best served by adopting rules that will permit the introduction of these unlicensed vehicular radar devices. We conclude that the public interest would best be served by maintaining the spurious emission level of 1000 pW/cm2, which provides adequate protection to radio astronomy observatories without being unreasonably restrictive for unlicensed vehicular radar devices. Accordingly, NRAO's petition for reconsideration is denied.

Spectrum Etiquette

5. In the Third Order the Commission adopted a spectrum etiquette for unlicensed operation in the 59-64 GHz band. Included in the spectrum etiquette is the reservation of the 59.0-59.05 GHz band as a designated coordination channel. In addition, the etiquette requires that any transmitter operating with a peak power equal to or greater than 0.1 mW in the 59.05-64 GHz band must transmit once every second a transmitter identification data block that contains the following: (1) The FCC identifier, which is programmed at the factory; (2) a manufacturer's serial number, also programmed at the factory; and (3) at least 24 bytes of user definable data.

6. In its petition, NEDD states that the requirement for a special coordination channel at 59.0-59.05 GHz will impose an unfair burden on developers of point to point systems and appears to violate the spirit of unencumbered commercial development. NEDD further states that because there is no specific protocol or definition for the transmitter identification data block and no database for these identifiers, it appears that the Millimeter Wave Communications Working Group (“MWCWG”) has proposed this etiquette to gain a tactical advantage over other innovators. NEDD provides no new facts to support its assertions.

7. The Commission reserved 50 MHz of spectrum and named it a coordination channel. However, we believe that the 50 MHz of spectrum would be more aptly referred to as a reserve channel. The reserve channel was established in order to save a 50 MHz block of spectrum for use as a future test bed to determine techniques for mitigating or eliminating interference that may occur between different unlicensed transmitters operating in the 59-64 GHz band. We believe that NEDD may have viewed the coordination channel as a requirement to utilize the 59.0-59.05 GHz band to coordinate the simultaneous operation of multiple unlicensed devices. As indicated in our rules, the 50 MHz of spectrum can only be utilized after receiving approval under the experimental authorization provisions of part 5 of the Commission's rules. As a result, our rules do not require any operation in the 50 MHz of reserved spectrum.

8. In order to provide manufacturers with maximum flexibility in the design of unlicensed devices that operate in the 59-64 GHz band, no specific method of encoding the transmitter identification was included in the Commission's rules. In its opposition to the NEDD petition, the MWCWG notes that the Commission's rules require each application for equipment authorization to specify how interested parties can obtain sufficient information, at no cost, to enable them to detect fully and decode the transmitter identification information, which can be used to identify a source of interference. MWCWG observes that this requirement simply provides manufacturers and operators with a tool to mitigate and resolve interference among unlicensed users of the 59-64 GHz band, without the intervention of the FCC.

9. We agree with MWCWG's observation that the sharing and coordination benefits provided by the transmitter identification requirement outweigh any burden it imposes. We find that the transmitter identification requirement does not thwart or delay development or deployment of unlicensed devices. Nor does the rule provide any tactical advantage to any manufacturer because all manufacturers of unlicensed devices that operate in the 59-64 GHz band have to comply with the requirement. Accordingly, the petition for reconsideration filed by NEDD is denied.

10. Pursuant to the authority contained in sections 4(i), 302, 303(e), 303(f), 303(g), 303(r), and 405 of the Communications Act of 1934, as amended, It is Ordered that the Petitions for Reconsideration filed by National Radio Astronomy Observatory and New England Digital Distribution, Inc., Are Denied.

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Federal Communications Commission.

Magalie Roman Salas,


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[FR Doc. 00-15578 Filed 6-20-00; 8:45 am]