I urge you to read Lou Frenzel's latest article on the road past 5G. If we even get 5G.
Lou describes accurately that the spectrum shortage is the most important roadblock to success of newer technologies.
Spectrum is like a tiny island. We are all trying to take the last seat on the tiny island. Even 10 years ago, there appeared to be lots of room, as spectrum was sucked up. The easiest pickings of the early days (1980s) were the under-used taxi cab spectrum frequencies. It was a wild goose chase after that. Billions upon billions of dollars were spent to grab tinier and tinier fractions of prime frequency. Now it is such a mess that only a giant chart can keep them all straight. (See map here.)
Unfortunately, two giant U.S. government agencies stand in the way of rapid development. They are the FCC (Federal Communications Commission) and the NTIA (National Telecommunications and Information Administration). They manage military and government spectrum. Some might say they are spectrum hogs.
Lou outlines the opportunities he sees ahead for squeezing or expanding the spectrum use. Just remember. There's no more where that came from.
There is NO new spectrum. Now what for cell phones?