LMCC Questions Satellite Downlink Operations at 460

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LMCC Questions Satellite Downlink Operations at 460 – 470 MHz

Tuesday, May 30, 2017 | Comments

The Land Mobile Communications Council (LMCC) submitted comments on the proposal set forth in World Radiocommunication Conference (WRC)-15 Resolution No. 766 to elevate satellite downlink operations to primary status in the 460 – 470 MHz band. The proposal could adversely impact more than 100,000 licensed private LMR (PLMR) operations if not implemented in a way that ensures protection of terrestrial operations from harmful interference, LMCC said.

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LMCC said there are at least 126,861 active licenses with at least one frequency authorized in the 460 – 470 MHz band. Examples of licensees using this spectrum include public-safety entities such as the Ohio State Highway Patrol, City of Chicago Office of Emergency Management and Communications, and Tennessee Department of Safety and Homeland Security, along with Orlando Utilities Commission, Wisconsin Power and Light, and Marathon Pipe Line.

Resolution 766 calls for studies to determine appropriate steps to avoid interference to terrestrial operations. LMCC recommends that the protective measures described below should be adopted as part of any expanded use of the 460 – 470 MHz band by satellites as part of WRC-19:
• Part 90 private land mobile spectrum users should be part of the process for formulating any changes in the rules governing satellite use of the 460 – 470 MHz band.
• Interested members of the PLMR industry should be part of the testing that is called for by Resolution 766 to confirm that terrestrial radio operations in the band can be protected from satellite communications. LMCC requested that it have a qualified representative present during the testing and made arrangements for such representative to be available for this process.
• Radios operating in the 460 – 470 MHz band should not be installed on any satellite until testing determines conclusively that terrestrial operations will be protected from interference.
• The use of a reduced power density limit, spread spectrum technology and other mitigation measures discussed in Resolution 766 as possible means to prevent interference to terrestrial users should be mandatory for satellites operating in the band.
• Continuous carrier or other modes of operation that do not monitor before transmitting should be prohibited on satellite radios operating in the band.
• Satellite operations in the 460 – 470 MHz band should not be allowed to operate on the low power pool channels designated in 47 CFR § 90.267, because the significantly lower power of such terrestrial operations make them more susceptible to interference.
• Radios designed for satellite use in the band should allow remote reduction of power and/or shut down when the satellite is passing over the United States, in case the interference protection measures implemented as a result of Resolution 766 prove ineffective once the satellite is launched.
• Until testing proves that terrestrial PLMR operations will be protected, LMCC cannot support co-primary status for satellite operations in the 460 – 470 MHz band.

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Comments

On 6/21/17, William Lowry said:

Ron, we do not need anyone encroaching on the amateur bands and to suggest the satellite guys to even look at the 70 cm band is asinine. Apparently you are not a amateur operator, and as an amateur, we take it as serious when someone begins to suggest any parts of the amateur band be used for anything.

On 6/1/17, Ron Wright said:

I am sure this will fail because like the article said, all of the 450 – 470 MHz UHF commercial band has heavy usage. But satellite guys might look at the 420 – 450 ham band, at least 420 – 430 MHz. 430 – 440 MHz has heavy usage in other parts of the world so I am sure it is protected from satellites. 440 – 450 MHz has heavy U.S. ham usage but only part used by hams in this band. Why don't satellites go to a part of the refarming of the upper TV channels in 600 – 800 MHz. I would think 10 megahertz from this segment could be found.