The mobile industry divides the available airwaves for cellular systems into two broad categories: the frequencies below 6 GHz (Frequency Range 1, for standards purposes) and the frequencies above 6 GHz (FR 2). Sub-6 GHz frequencies are the ones which have historically been used to build cellular systems, generally from a range of about 600 MHz to the “midband” frequencies from around 2.5-4 GHz. Unlicensed frequencies at 5-6 GHz can be used for cellular in the form of License-Assisted Access as well.
