Meteorologists express concern over 5G bandwidth allocation

The World Meteorological Organization (WMO) has warned the decisions of a major radiocommunication conference may be too lenient to avoid an adverse impact on Earth observation satellite systems.

The World Radiocommunication Conference 2019, organized by the International Telecommunications Union and attended by more than 160 nations, agreed on the allocation of bandwidths of the world’s radio spectrum.

The WMO has expressed concern that the emergence of 5G means “demand is now over stripping the limited supply” of bandwidths. The conference agreed to protect the microwave bands that support severe weather early warning systems, but with time-limited provisions, which leaves the future of these systems uncertain.

“Potential effects of this could be felt across multiple impact areas including aviation, shipping, agricultural meteorology and warning of extreme events as well as our common ability to monitor climate change in the future,” said WMO secretary-general Petteri Taalas.

Severe weather early warning systems are dependent on access to specific radio spectrum bandwidths. 5G’s reliance on the same bandwidth areas threatens to limit the usability by meteorological observation systems around the world.

The decision made at the WRC restricts 5G technologies from emitting noise in the 24GHz meteorological satellites observation frequency band below -33 dB(W/200MHz), which could lead to nearly 10 times more interfering out-of-band emissions than what WMO had recommended to allow.

As a result, a limit of -39dB(W/200MHz) will apply to IMT base stations and a limit of -35dB(W/200MHz) will apply to IMT mobile stations. However, these limitations will only apply to stations brought into use after 1 September 2027.

For stations brought into use prior to this date, the limit will not apply, either before or after the deadline. Base stations will remain subject to a limit of -33dB(W/200MHz) while mobile stations will remain subject to a limit of -29dB(W/200MHz).

The risk here, according to the WMO, is that if 5G technology rolls out faster than anticipated, there could be an “unregulated increase in interference” in the same frequency radio spectrum band that severe weather warning systems rely on.