AT&T just changed its mind about deploying fixed wireless. The operator has been touting its plans to deploy a mobile 5G network in 12 markets in the United States this year using millimeter wave (mmWave) spectrum in the 28 GHz and 39 GHz bands. And while it still plans to move forward with those deployment plans, it announced today that it will deploy fixed wireless in late 2019 using the unlicensed Citizens Broadband Radio Service (CBRS) spectrum. It will initially deploy LTE but then migrate to 5G. The company did not say how many markets it would deploy.

AT&T’s plans to deploy fixed 5G wireless are particularly interesting because previously the company said it found fixed wireless to be too costly for a residential broadband deployment due to the expenses involved in adding fiber and small cells to backhaul the traffic from the mmWave antenna to the cell site.

It appears that those cost efficiencies may have changed because AT&T plans to use unlicensed CBRS spectrum, which doesn’t require it to purchase costly spectrum licenses.

Gordon Mansfield, vice president of converged access and device technology at AT&T, said in a statement that the company will use the CBRS fixed wireless solution to deliver broadband to residences and enterprises. He noted that there are millions of households across the U.S. that still lack access to broadband services and that fixed wireless could be a more cost-effective solution than fiber to reach those homes and businesses.

“When we looked at CBRS spectrum, we saw a promising opportunity to use this spectrum band to expand our fixed wireless access network to additional cities across the U.S as well as other opportunities for future use cases,” said Mansfield.

The company said it plans to start testing its CBRS gear in its labs in early 2019 and then commercially deploy it in U.S. cities in late 2019.

Of course, another reason AT&T may have changed its tune on fixed 5G wireless is that it may be increasingly concerned about what its competitor Verizon is doing. Verizon has said it will launch fixed 5G wireless in four markets this year. These initial four markets will use the company’s proprietary pre-standard 5G equipment. But it has said it will quickly move to standards-based 5G New Radio (NR) technology in 2019 as soon as manufacturers can make customer premises equipment (CPE) available.

AT&T will use Samsung’s CBRS-compliant radios and base stations and CommScope’s spectrum analyzer system (SAS) for its fixed wireless deployment.

This deal is particularly advantageous for Samsung, which has been scoring a lot of 5G deals with U.S. carriers. The company also is working closely with Verizon on its planned 5G deployments and is a long-time supplier to Sprint.

Using the unlicensed 3.5 GHz CBRS spectrum band is not without challenges. The spectrum is currently being used by government radar systems, such as the Navy. But SAS administrators like CommScope need to know where those users are in order to give them priority to the spectrum. The rest of the spectrum is then available to be used by others. While many wireless operators want to use the spectrum for 5G, there are a lot of diverse users that also want access to that spectrum, including industrial IoT players, and wireless Internet service providers.

The FCC has set up a unique sharing situation for CBRS in the U.S. that involves a combination of licensed and General Authorized Access (GAA)-designated spectrum. The spectrum band also has a Priority Access License (PAL) portion that is still awaiting rules from the FCC.