In the U.S. market, 3.5 GHz and 5 GHz are the frequency bands where spectrum sharing is going to be extended, each featuring a unique approach to sharing.

Internationally, 5 GHz is likely to see the first deployment of new sharing methods. In South Korea, about 530 MHz of spectrum is available in similar bands. In China, about 325 MHz is available.

In Japan, about 450 MHz is potentially available for Wi-Fi purposes. In the United States, about 555 MHz is available for new Wi-Fi applications. In the European Union about 455 MHz is available.

The technology issue is to create LAA access systems that ensure LTE access imposes no more load on the Wi-Fi resource than any other Wi-Fi device would.

In the 3.5 GHz band, one would in the past have witnessed a complicated process whereby existing licensed users transition off the band to new frequencies, while new users eventually are allowed to then use the spectrum.

Instead, and for the first time, licensed users will continue to use the original spectrum, while additional groups of users are allowed to share the capacity when spare bandwidth is available.

As planned, the  3550-3700 MHz band would be governed under a three-tier system.

The top tier would be reserved for federal and non-federal incumbent users including the Defense Department.

The lowest tier, General Authorized Access (GAA), would be open to any FCC-certified device.

The middle tier, dubbed the Priority Access tier, would make available Priority Access Licenses (PAL), or “targeted, short-duration licenses,” for auction, presumably to commercial users requiring more bandwidth predictability.

Sharing in the 5-GHz band will operate differently. Designated as a new band for Wi-Fi, licensed mobile carriers would be able to contend for use of capacity using a protocol known as License Assisted Access (LAA).

License Assisted Access would allow licensed Long Term Evolution 4G providers to bond or aggregate 5 GHZ Wi-Fi spectrum with licensed LTE frequencies.