The US operators, and the FCC, have made a virtue out of necessity by taking some creative approaches to address their shortage of optimal
5G spectrum. While the 3.5 GHz C-band is the primary new spectrum band in which most first-phase 5G networks are being rolled out, in the USA, this is occupied by federal and other incumbents. With the US operators lacking access to significant amounts of spectrum in this band, they will be denied the economies of scale of a global ecosystem, and AT&T and Verizon will be at a disadvantage to Sprint (and T-Mobile, assuming they merge), which has midband spectrum in 2.5 GHz.
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