Mid-Band Spectrum: the Goldilocks Bands

Today’s announcement from the Federal Communications Commission that it is launching a “Notice of Inquiry” for mid-band spectrum is a development that wireless users can cheer, just as industry players already have.

That’s because by the time this spectrum gets released for commercial use in a couple of years, rising demand for wireless data from phones, tablets and other devices will easily be able to access and utilize this new spectrum. Industry is cheering because this spectrum is terrific for small cell networking – neither too low (which is best for wide area mobility) nor too high (mid-band spectrum propagates through walls easier than millimeter wave). Just like the Goldilocks fairy tale, this spectrum is “just right.”

Moreover, the distinctions the FCC is making between licensed on the one hand, and unlicensed on the other, make good sense from a technology perspective. The bands under consideration are contiguous to other “like” bands: 3.7-4.2 GHz sits adjacent to the existing Consumer Broadband Radio Service, which is expected to use LTE technology for licensed and unlicensed connectivity. The 6 GHz unlicensed band is next to the existing 5 GHz band for unlicensed that uses Wi-Fi, sometimes referred to by its “standards” name, IEEE 802.11. In both bands, these adjacencies enable extensibility of radio technology, from the existing band into the new one. By way of example, IEEE 802.11ax – the next generation of Wi-Fi – will be able to extend from 5 GHz into 6 GHz channels.  In fact, under the FCC’s plan, unlicensed would extend all the way up to 7125 MHz.

The FCC’s focus on mid-band spectrum for small cell networking is exactly right. Most of the data we generate from our devices is generated when we are indoors, at home (especially during peak hours in the evenings) or at work – places where it’s proven that small cells are successful. US peak Internet traffic will grow at a compound annual growth rate of 32% from 2016-2021, according to Cisco’s Visual Networking Index report. And that evening peak is supported in the main by home Wi-Fi networks connected to a wired broadband network.

Mobile data traffic using licensed spectrum is growing also. In the US, the average mobile connection will generate not quite 12 Gigabytes of Internet traffic per month in 2021, up from about 3.5 Gigabytes today.

Tough work lies ahead to open these bands to use by consumers. The bands identified have significant and important incumbent licensees whose operations will need to be protected from interference. There are a lot of issues to be resolved.

That said, the decision taken today by the FCC helps ensure that the user experience will continue to get better in the future, powered by additional spectrum availability.