T-Mobie 5G streak with 600 MHz, amidst AT&T and Verizon 28 GHz debut.

T-Mobile US says it has completed the first 5G data and video calls using 600 MHz spectrum, as it aims to build out nationwide availability of 5G service by 2020.  The calls were conducted on a live, commercial network, according to T-Mobile US. 

"Low-band 600 MHz spectrum delivers a broad layer of 5G and provides much-needed balance to millimeter wave (mmW) – which is an important piece of the 5G puzzle – but has limited coverage (less than a square mile) and is unable to pass through most objects, like walls," T-Mobile US said in a statement on its tests.

T-Mobile US said that during the tests, its teams "generated a 5G signal capable of covering more than a thousand square miles from a single tower".

T-Mobile also test cross spectrum call on 600MHz, 28GHz, and 39GHz spectum bands. 

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