The FCC recently made a Notice of Proposed Rulemaking (NPRM) regarding its announcement to free up unlicensed spectra to be used for a variety of technologies, most notably, Wi-Fi. (This topic is discussed in previous blog posts here and here.) The NPRM discussion is broken down into two sections, (1) The Current UNII Bands, and (2) Future Unlicensed Operations at 5 GHz. The FCC plans to open two new 5 GHz bands: UNII2B, which would be 120 MHz wide between 5350 and 5470 MHz, and UNII4 which would be 75 MHz wide between 5850 and 5925 MHz. As announced by the FCC Chairman, and mentioned in our previous blog posts, this increases the spectrum available to unlicensed devices in the 5 GHz band by about 35% or 195 MHz.
The chart below, found in the NPRM, summarizes the frequency bands for UNII device operation. It also indicates that unlicensed devices may be authorized to operate in the U-NII-3 band, as well as the 25 megahertz between that band and the potential future U-NII-4 band.
The frequency bands for U-NII device operation
Additionally, the FCC mentions simplifying certain technical requirements for UNII devices to ensure that these devices do not cause RF interference and can continue to operate in the 5 GHz band. Specifically, they mention removing restrictions from the UNII 1 band (increase TxPWR, and remove the indoor restriction), and harmonize 5825 to 5850 with UNII3 rules (yielding another channel). The FCC also discusses a database registry.
In regards to these plans, the FCC states "We believe that an increase in capacity gained from 195 megahertz of additional spectrum, combined with the ease of deployment and operational flexibility provided by our UNII rules, would continue to foster the development of new and innovative unlicensed devices, and increase wireless broadband access and investment."