Google is asking the FCC for permission to hold more tests on 3.5GHz-based CBRS LTE-based services in Texas, which -- beyond 2018 -- could enable the shared mid-band spectrum to be used for localized multi-megabit public and private 4G broadband services, as well as expanding coverage for smartphone users with compatible devices, eventually.

The Federal Communications Commission (FCC) originally alighted on the 3.5GHz band for usage in April 2015 -- dubbed the Citizens Radio Broadband Service (CBRS) -- for broadband applications. The 150MHz of spectrum in the band will be shared with US Navy radars, with a database to allocate available spectrum. The FCC has previously said that it will auction off 70MHz of spectrum for three-year licenses, while 80MHz would be left for public access.

The census tract-based licenses initially proposed by the FCC could be very small scale compared to traditional geographical spectrum licenses in the US. They would allow, for instance, enterprises to create their own private LTE networks on campus, using dedicated small cells.

So, Google (Nasdaq: GOOG) is now asking the Federal Communications Commission (FCC) for an experimental permission to carry out mobile and "transportable" tests with 3.5GHz LTE equipment in Fort Worth and Plano, Texas. Much of the documentation in the early April request from Google, however, is redacted.

The "STA will enable continued testing of radios in a way that is likely to contribute to the development, extension, expansion, or utilization of the radio art," Google tells the FCC.

Google started testing 3.5GHz LTE in 20 markets in 2016. It has also carried out high-speed tests and more. (See Google Looks to Test 3.5GHz Broadband Radios, Google Taking 3.5GHz Tests to NASCAR and Google, Nokia & Qualcomm Racing Towards 3.5GHz.)

This comes hard on the heels of Verizon Wireless kicking off 4G tests too. (See Verizon Tests 4G CBRS With Partners.)

Google is a big proponent of using LTE small cells in the mixed-use CBRS 3.5GHz band. The FCC had initially proposed an auction off 70MHz of 3.5GHz licenses for three years at a time (or up to six years when the licenses are initially bought). 80MHz of public access licences (PAL) spectrum would be left for open general access usage. (See US Interest Grows in 3.5GHz Wireless Broadband .)

A newer Notice of Proposed Rulemaking (NPRM) issued by the FCC in October 2017 asked for public comment on allowing Public Access Licenses (PALs) to cover wider geographical areas and be offered for longer terms. This would be far more like a traditional 3G or 4G spectrum license. (See FCC's Latest 3.5GHz Vote Favors the Big 4.)

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T-Mobile, meanwhile, has asked the FCC to make the 3.5GHz band part of a wider band for 5G. (See T-Mobile Calls on FCC to Open 3.5GHz for 5G.)

All of this talk about how this spectrum will be used is coming to a head soon. The FCC is expected to make a final decision on how the spectrum will be utilized within the next couple of months.

— Dan Jones, Mobile Editor, Light Reading