MIMO antennas extend the easily usable frequencies well beyond the 4.9 GHz band. The FCC took the first step with a Notice of Proposed Rulemaking. Claus Hetting of Wi-Fi Now kindly allowed me to reprint his report.
The FCC wants to introduce four new unlicensed subbands aptly named U-NII-5 to U-NII-8. In the case of U-NII-5 and U-NII-7 (a total of 800 MHz) a new scheme called AFC (‘Automated Frequency Control’) will protect some incumbent 6 GHz users (mostly point-to-point microwave links) from harmful interference, the FCC says. In these two subbands the FCC wants to allow the operation of ‘standard-power access points’ equivalent to current rules for U-NII-1 and U-NII-3 subbands.