Industry Voices—Mun: Carriers benefit from unlicensed and shared band use

As of late, it seems there is no shortage of spectrum coming available for mobile use. South Korea recently auctioned off 280 MHz of the 3.5 GHz band and about 10x that amount in the 28 GHz band, and China is soon expected to release hundreds of MHz of the 3-5 GHz band for 5G. In the U.S., FCC is moving quickly to hold millimeter wave spectrum auctions across the 24-47 GHz bands, in addition to finalizing a ruling for the 3.5 GHz CBRS band and possibly the 3.7-4.2 GHz band. In the midst of a seemingly abundant “sea” of licensed spectrum, one would think that carriers would prefer to simply deploy infrastructure only in their licensed spectrum bands. However, we see growing carrier investments in the unlicensed and shared spectrum bands.

While the interference protection that comes from licensed spectrum is essential for large-scale nationwide buildout of mobile networks, carriers also see the benefits of localized unlicensed spectrum use in certain places. Residential home broadband market is a good example of this as Wi-Fi has become a de facto choice for fixed broadband carriers as well as for converged mobile/telco operators. The coming transition to 802.11ax is expected to alleviate much of the pain points associated with dense deployments. (While we believe OFDMA and 8x8 MU-MIMO will be welcome features in the new 802.11ax technology, at some point, additional unlicensed spectrum will be needed to alleviate congestion with an unabated growth in the number of devices and data traffic.) For some enterprising wireless ISPs, unlicensed bands in rural markets even provide a good use case for applying 802.11-based solution to provide fixed wireless broadband service.

As the examples show, the use of unlicensed Wi-Fi vs. licensed LTE/5G depends on use case and application. If a carrier already has a backhaul connectivity to a site location, as is the case in the residential broadband case, leveraging Wi-Fi in the customer premise equipment (CPE) such as broadband gateway is a slam dunk case of wirelessly connecting multiple user and IoT devices to extend carrier services within customer premise. In public “hotspot” outdoor cases, using LTE-based unlicensed technology like LAA to enhance mobile experience may be more advantageous, in terms of leveraging LTE core network. As long as the carriers are making direct network investments, they will choose what technology makes most sense depending on places and applications that they are trying to address. 

The success of Wi-Fi will continue to flourish in the enterprise WLAN market and consumer retail wireless networking as unregulated innovations in business models and technology adoption continue to expand. The growing ecosystem in turn enables a bigger scale for lower-cost chipset solutions. Efficient utilization of spectrum, whether it’s licensed, unlicensed and shared, and the choice of technology—whether Wi-Fi or LTE/5G—will depend on where and who is deploying the infrastructure and for what purpose.  There is a good symbiotic relationship between unlicensed and licensed ecosystems, and carriers appear to understand the benefits of investing across all types of spectrum. Regulators hopefully also see the benefits of opening more licensed and unlicensed/shared spectrum.

Kyung Mun is a senior analyst at Mobile Experts LLC. Mobile Experts is a network of market and technology experts that provides market analysis on the mobile infrastructure and mobile handset markets. Over the course of his 20+ years in wireless and cable industries in a dynamic range of roles from engineering to product management and technology strategy, Mun has contributed to the advancement of mobile communication while working at leading companies in the mobile value chain including Motorola, Texas Instruments, Alcatel-Lucent and a few startups in between. He holds undergraduate and graduate degrees in electrical engineering from the University of Texas at Austin and Georgia Tech, and studied finance and strategy at Southern Methodist University.

Industry Voices are opinion columns written by outside contributors—often industry experts or analysts—who are invited to the conversation by Fierce staff. They do not represent the opinions of Fierce.