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BAS ENG operations protected in FCC Report and Order on DOD 2 GHz Uplinks

The FCC has released the Seventh Report and Order on allocation of spectrum to new Advanced Wireless Services (AWS). As reported in last week's RF Report, the FCC relocated U.S. Department of Defense (DOD) uplinks from the 1.7 GHz band into the 2 GHz broadcast auxiliary service (BAS) band to clear the 1,710-1,775 MHz spectrum for AWS. In the Report and Order, the FCC took several steps to protect broadcast microwave links from interference. The Society of Broadcast Engineers filed comments and reply comments expressing concern about interference to ENG receive sites from the DOD uplinks.

Although the FCC will allow the DOD to use the 2,025-2,110 MHz band on a co-equal, primary basis with non-federal government operations for earth stations at 11 sites, the Report and Order said "we are maintaining in the 2 GHz band our longstanding policy that first-licensed facilities have the right of protection from later-licensed facilities operating in the same band. This means that a new DOD TT&C uplink earth station seeking to operate at 2 GHz must coordinate with all BAS stations that may be affected by the new earth station's operation." The FCC said the DOD must coordinate facilities "only when construction and/or implementation are anticipated, and prior to authorization." Furthermore, "To ensure that such coordination occurs successfully, prior to authorization, DOD must coordinate the DOD TT&C uplink earth station with all potentially affected incumbent BAS, CARS, and LTTS licensees of stations within the coordination contour of the earth station, consistent with Appendix 7 of the ITU Radio Regulations, and engage the local BAS frequency coordinator(s), where available, in support of achieving such coordination." If coordination can't be negotiated, FCC and NTIA may join to arbitrate resolution. DOD earth stations are required to maintain a point of contact for coordination.

SBE noted that the coordinates for some of the earth stations were incorrect. The FCC Seventh Report and Order includes a revised list of locations and coordinates. These are:

- Naval Satellite Control Network, Prospect Harbor, Maine; 44° 24' 16" N 068° 00' 46" W
- New Hampshire Tracking Station, New Boston AFS, N.H.; 42° 56' 52" N 071° 37' 36" W
- Eastern Vehicle Check-out Facility & GPS Ground Antenna & Monitoring Station, Cape Canaveral, Fla.; 28° 29' 09" N 080° 34' 33" W
- Buckley AFB, Colo.; 39° 42' 55" N 104° 46' 36" W
- Colorado Tracking Station, Schriever AFB, Colo.; 38° 48' 21" N 104° 31' 43" W
- Kirtland AFB, N.M.; 34° 59' 46" N 106° 30' 28" W
- Camp Parks Communications Annex, Pleasanton, Calif.; 37° 43' 51" N 121° 52' 50" W
- Naval Satellite Control Network, Laguna Peak, Calif.; 34° 06' 31" N 119° 03' 53" W
- Vandenberg Tracking Station, Vandenberg AFB, Calif.; 34° 49' 21" N 120° 30' 07" W
- Hawaii Tracking Station, Kaena Pt, Oahu, Hawaii; 21° 33' 44" N 158° 14' 31" W
- Guam Tracking Stations, Anderson AFB, and Naval CTS, Guam; 13° 36' 54" N 144° 51' 18" E

SBE's filings noted that a desired-to-undesired (D/U) ratio of 60 dB or more is needed to ensure there is no harmful interference from a co-channel uplink to an analog ENG-receive-only site, but that this could possibly be reduced to 30 dB once broadcasters have converted to digital ENG. The FCC observed, "By the time DOD earth stations begin to use the 2 GHz band, total or near-total conversion to digital BAS operations is likely to have occurred." Motorola commented that DOD satellite using 2 GHz frequencies will not be available "for at least several years." In addition, according to the Report and Order, "DOD may choose not to use the 2 GHz band for some of its 11 existing sites that currently operate in the band 1761-1842 MHz due to coordination difficulties with incumbent operations."

In addition to allowing fixed DOD earth station uplinks to share the 2 GHz BAS band, the FCC also allowed DOD to use the band for fixed and mobile services (except aeronautical mobile) on a secondary basis at six sites in "remote locations in the southwestern United States." The six sites are Nellis AFB, Nev.; China Lake, Calif.; Ft. Irwin, Calif.; the Pacific Missile Test Range in Pt. Mugu, Calif; Yuma Ariz.; and the White Sands Missile Range in New Mexico. Operation at these locations is on a secondary basis and must protect primary operations such as broadcast ENG. The FCC Report and Order states, "Upon request, primary users must provide sufficient information to allow secondary military users to protect the primary operations."

For more information on other spectrum affected by the DOD uplink relocation, see the FCC's Seventh Report and Order on allocation of spectrum to new Advanced Wireless Services (AWS).