German carrier Deutsche Telekom and Chinese tech giant Huawei this week said they conducted a trial of 5G communications in the 73 GHz band — the first over-the-air field tests of multi-cell high millimeter wave technology in the world.

The companies tested the system in various indoor and outdoor scenarios at carrier’s headquarters in Bonn, Germany, including evaluating the impact of glass buildings, indoor office settings and foliage.

The tests incorporated MIMO technology and advanced antenna systems with adaptive beamforming and beam tracking to achieve more than 1 Gbps speeds at a distance of 240 meters across line-of-sight conditions, officials said.

Huawei Wireless CTO Wen Tong said MIMO technology in the mmWave spectrum known as the e-band could achieve “fiber-like speed for mobile broadband access.” Deutsche Telekom research SVP Alex Jinsung Choi added that the trial “opens up a new door for applications and deployments of 5G mmWave.”

“The verification of these features in our world’s first multi-cell 5G high mmWave field tests will point out the future direction for the industry’s ultra-high broadband experience for customers in both indoor scenarios as well as in extremely crowded areas,” Choi said.

The companies are also partnering with Intel to demonstrate 5G interoperability.