US Federal Communications Commission Against Meteorologists
Artistic rendering of the NOAA meteorological satellite
Meteorologists and other experts urge the US Federal Communications Commission (FCC) to abandon the plan for sharing the frequency spectrum, which, they said, could interfere with the transmission of satellite weather images. Experts say meteorological satellite data transmission is at risk because of the FCC plan.
The controversy relates to the frequency range 1 675-1 680 MHz, which is shared by NASA, the National Oceanic and Atmospheric Administration (NOAA) and the US Navy.
The American Geophysical Union (AGU), the American Meteorological Society (AMS) and the National Meteorological Association (NWA) told the FCC last week that its plan for the frequency range 1675–1680 MHz should be canceled due to the “probability of receiving interference” of meteorological satellite images and relayed environmental data for reception-only antennas used by representatives of US enterprises in the areas of weather, water and climate. "
The 1 675-1 680 MHz band is now used by NOAA for government-owned satellites that transmit data to terrestrial antennas, but the FCC, led by Ajit Pai, has proposed rules that will force federal government users to use the frequency spectrum with wireless broadband services. The FCC targets the 1675-1680 MHz band in part because it is adjacent to the 1670-1675 MHz band, which is already allocated for wireless services.
Spectrum reallocation is necessary so that "national wireless networks keep up with the ever-growing demand for wireless broadband," the FCC said. On June 22, 2019, the Federal Communications Commission notified the media of its plans. If the FCC finally approves the plan, an auction will be opened for the sale of licenses in the range 1675-1680 MHz to wireless network operators.
Successor LightSquared wants spectrum
The main supporter of the FCC plan in the 1675-1680 MHz region is Ligado, formerly known as LightSquared, which failed to obtain government permission to create a 4G-LTE network in a different spectrum in 2012, because testing showed that the network would interfere with GPS devices. Now Ligado is trying to build a 5G network.
Ligado requested the FCC to open the 1675-1680 MHz spectrum for sharing in 2012 and since April has made 10 applications in support of the current FCC plan. Ligado already leases access to adjacent 1670–1675 MHz, which it can combine with 1675–1680 MHz to obtain a 10 MHz band of continuous spectrum. Ligado claims that there is no reason for concern about interference with data transmission from a weather satellite.
The FCC spectrum plan is also supported by CTIA, the wireless lobby group that represents AT&T, Verizon, T-Mobile and Sprint.
In addition, Ligado also asked the FCC this week to decide on a license in December 2015 to change the license, which would allow it to use the 1,526-1536 MHz band with power level restrictions to protect GPS devices. Including other bands, Ligado aims to build a 5G network with a bandwidth of 40 MHz.
Boeing and AccuWeather express concern
Boeing, a frequent government contractor, explained in the application that the 1675-1680 MHz spectrum “is used by the FAA, NASA, NOAA, the National Meteorological Service, the Ministry of Defense, the Ministry of the Interior and the Ministry of Agriculture to receive real-time data from transmitting channels from geostationary environmental satellites "GOES", which includes weather information and hydrological (ie flood) information. "
There are also many users who “operate unregistered, earth-only earth stations for receiving GOES weather and flood data, including users in the aircraft industry, state and local governments, and when sending for environmental monitoring, operational disaster planning and preparedness. Boeing said it uses the spectrum "for communications, including flight tests of aircraft manufactured for the US government, and for the development of wireless communications equipment for both commercial and government use."
Internet system may be less reliable
A request from the Federal Communications Commission (FCC) for public participation asked whether the “existing content delivery system via the Internet or private network” could be used in place of the existing system to make GOES data available without the use of earth stations.
Boeing objected that “the Internet does not provide real-time reception of GOES data” and that its speed and reliability may not be compatible during disasters.
AccuWeather also said in a FCC statement that the current satellite system “was designed with a 99.988% uptime for a 30-day period, leaving room for downtime of just 5 minutes per month.” Internet services will not necessarily provide the same level of uptime, “especially during natural disasters,” the company said.
“After Michael’s hurricane hit the Gulf of Mexico in 2018, many fiber-optic lines were cut and major carriers had to deploy mobile towers to support Internet functionality during this unprecedented downtime,” AccuWeather told FCC. “It was at this time that satellite data was most needed, and GRB [GOES Rebroadcast] required a small infrastructure, relying only on the cable connecting the satellite dish to the data center. Even if there was a private Internet network or fiber used by the CDN, they could become unusable in the event of a natural disaster such as Michael. The GRB system also has lower latency, said AccuWeather.
AccuWeather is skeptical that the FCC can prevent interference by setting power limits on broadband networks in the 1675–1680 MHz band. According to AccuWeather, when transmitting data from a satellite, “the transmit power of the communication line is much weaker than what would be used by the wireless network, and it could be completely overloaded.”
The Weather and Climate Industry Association of America (AWCIA), a trade group for weather professionals, has argued that “radio frequency interference that can be generated from strong terrestrial transmission lines that have the same spectrum as relatively weak GOES signals in space,” will have a devastating effect on our members.
According to AWCIA, during severe storms and natural disasters, cellular and other broadband networks are “often taxed to the maximum.” In contrast, existing GOES satellite data reception systems “are always present and have very little infrastructure that can be damaged in stressful conditions,” the group said.
The threatened spectrum
NOAA has not yet filed a protest with the FCC. But the February 2018 Florida Department of Transportation (FDOT) document describes a joint study conducted by FDOT and NOAA, and says that weather-related applications of the 1675-1680 MHz spectrum are “threatened” by signals from neighboring bands.
The spectrum used for GOES has already "been reduced by more than half compared to 20 years earlier," and "the spectrum on both sides of the GOES transmission line is now used for cellular communications," the FDOT document says.
The Ligado Plan for the spectrum “will protect only a limited number of federal earth stations” and “no non-federal earth stations will be protected,” the document also says.
“If Ligado is allowed to share the spectrum at a frequency of 1675-1680 MHz, there is a high probability that there will be a negative impact on the performance of the earth station,” the statement said.
NOAA is currently conducting research on how spectrum sharing can affect meteorological services, the American Geophysical Union, the American Meteorological Society and the National Weather Association said in a statement. The groups encouraged the FCC to wait until the study is completed before taking any action.