The new 5G cell towers that generated controversy this year are well designed to limit radio-wave interference on airliners, according to a US government study that appears to show the technology can soon safely coexist with aviation.

Researchers found that 5G transmissions stay safely within their assigned frequencies and mostly don’t point signals skyward where aircraft operate, according to the report released Oct 11, the first of several from the government on the new high-speed mobile phone service.

There is a "low level of unwanted 5G emissions” in frequencies used by so-called radar altimeters - which calculate a plane’s distance from the ground and are critical to landing in low visibility - the National Telecommunications and Information Administration said in the report.

The findings offer the the strongest indication to date that the patches being applied to some aircraft models should work well to protect them.

The introduction of AT&T Inc and Verizon Communications Inc’s 5G service in January produced months of controversy and led the Federal Aviation Administration to push companies to reduce power levels near major airports after it concluded they could cause altimeters to give dangerous, inaccurate readings. In June, the FAA began pushing airlines to attach protective filters to the altimeters in a compromise to allow the full use of 5G.

The FAA has said the existing limits on signals by the two cell companies will have to remain in place until the patches are installed on aircraft because some models are susceptible even when the 5G signals are well controlled.

The NTIA, the government’s arbiter of radio-frequency disputes, conducted the testing in conjunction with the Defense Department, and was joined by other federal agencies and representatives of telecom companies and the aviation industry. The NTIA tested all three of the 5G broadcast-tower technologies used by AT&T and Verizon in a variety of real-world conditions.

 - Bloomberg