5G mmWave – Patience or Persistence?

By Elena DeJaco

The Federal Communications Commission (FCC) and European telecommunications regulators are looking to release more millimeter wavelength (mmWave) spectrum, even as previous mmWave remains relatively unused.  Doubling down on mmWave would cause more “greenfield spectrum” to sit idle.  Thus, this blog explores the status of mmWave in the United States and Europe and why regulators should carefully craft future license requirements if they release more of the spectrum.  It will describe the early mmWave optimism and successful applications, the current underutilization of mmWave licenses, and the future plans of regulatory agencies to offer more mmWave licenses.

Generally, mmWave refers to the frequency range between 20 and 100 GHz.  This spectrum band received significant attention in the early days of the 5G research cycle.  It was attractive as greenfield spectrum, meaning it does not have many incumbent users.  Mobile network operators could easily acquire hundreds of megahertz of contiguous and exclusive spectrum in this range.  Additionally, this spectrum can transmit significantly more data, faster and does not require extensive regulatory schemes or expensive relocation activities.

For these reasons, there was significant energy and optimism surrounding mmWave for 5G.  Specifically, the  International Telecommunication Union’s 2019 World Radiocommunication Conference identified 26 GHz, 37.6-43.5 GHz, 45.5-47 GHz, 47.2-48.2 GHz, and 66-71 GHz as key 5G bands.  Early energy was propelled by companies like Qualcomm, who invested in the technology, and mobile operators like Verizon, who followed suit in spectrum auctions.

However, mmWave presents engineering challenges that have dampened initial optimism.  For example, 5G mmWave signals may transmit over about a third of a mile.  With carriers used to setting up towers every several miles, mmWave would require mobile carriers to expand deployment capabilities significantly.  This translates to a tremendous increase in infrastructure costs and time to obtain necessary permits and site locations to fully deploy services.

However, we should not underestimate mmWave.  5G mmWave has been successfully deployed in venues like airports and stadiums where massive crowds seek to access large amounts of data.  For example, Verizon has recorded substantially faster download and upload speeds in these dense environments using mmWave.  Also, carriers have begun to offer Fixed Wireless Access (FWA) using mmWave spectrum.  FWA provides home and business internet access through radio spectrum rather than cable or fiber.  FWA costs less to deploy than cable or fiber and is emerging as a viable alternative to fixed-line approaches.  It is still a relatively young technology with limitations compared to traditional internet access offerings.  However, US Cellular has seen success and recorded mmWave FWA as 10-15 times faster than previous technologies.  Broadly, FWA accounted for 90% of new broadband subscribers in 2022.

Status of mmWave in the United States

There has been some mmWave 5G deployment in the United States by major carriers; however, it is not a significant part of telecommunication networks, nor have deployments met expectations.  In 2018, the FCC began to auction mmWave spectrum with the understanding that it would be used for 5G networks.  In its Auction 102 and 103, the FCC auctioned 24 GHz, 28 GHz, 37 GHz, 39 GHz, and 47 GHz spectrum.  Mobile carriers invested $9.2B in a total of 4.95 gigahertz of spectrum.  This is about 25 times the amount of spectrum auctioned in the well-known C-Band auction.

Attached to the mmWave auctions are requirements for winners to prove they cover about 40% of the population under each license.  This means that not only do carriers need to deploy in each licensed city, but they also need to cover 40% of the households in each licensed city.  It is about halfway through the 10-year build-out period, which will last until 2029.  The FCC expressly declined to set an interim benchmark for deployment because it understood the uncertainty of the technology, and it believed carriers would not meet such a deadline.

Accordingly, we can only evaluate mmWave 5G deployment through self-reported statistics from licensees.  For example, US Cellular, one of the major licensees of 28 GHz, has recently announced that it covers 125,000 households in 30 cities with mmWave.  The company has licenses in 38 cities and may be on track to cover each city by 2029.  However, it will need to cover over 400,000 households because some of its licenses include higher-population cities such as Oklahoma City, Tulsa, Omaha, Des Moines, and Madison.  Thus, US Cellular is only about one-fourth of the way toward the requirement to reach 40% of the population under each license.

Additionally, AT&T is offering a service called 5G+, which utilizes mmWave.  In January 2023, AT&T announced that this service is available in parts of  50 cities and 70 venues.  AT&T won licenses to about 160 cities in Auction 102.  As such, even with a generous assumption that AT&T covers 40% of the population in the 50 cities deployed so far, it would still meet only about one-third of its license requirements.  Verizon has also announced that with its’ 1,000 megahertz of mmWave spectrum in major license areas, it has deployed about 40,000 cell sites.  Based on these numbers, estimating the deployment statistics is difficult, although many view Verizon as the carrier with the most substantial mmWave deployment.

These deployments pale in the face of build-out requirements and what would be required for mmWave to become a significant part of the United States’ 5G infrastructure.  In fact, T-Mobile, widely considered the leader in 5G, is attributing its leadership to not focusing on mmWave when compared to AT&T and Verizon.  Carriers like Verizon, who had initially concentrated on mmWave deployments, have now turned their attention to C-band.  With momentum shifting towards lower mid-bands like C-band, it is unlikely that these deployment statistics will significantly change in the next few years.

Status of mmWave in Europe

Typically, Europe and the United States converge on spectrum policy so that all countries can use the same equipment and deploy similar systems.  This lowers the cost of investing in networks and enables growth; however, Europe is not harmonized with the United States on mmWave spectrum policy.

The EU initially mandated that Member States auction the 26 GHz band by the end of 2020.  The EU relaxed this requirement in the wake of Covid-19 and the subsequent economic downturn.  Now, EU Members States are required to auction 26 GHz only if there is demand for it.  Currently, just Bulgaria, Estonia, Germany, Greece, Finland, and Spain have assigned 26 GHz licenses.   Notably, no carriers bought licenses when Montenegro and Macedonia attempted to auction the band.

Future mmWave Releases

Overall, mmWave deployments have not met expectations.  Dan Hayes, partner at PwC, said early mmWave auctions were the “greatest failure of the wireless world in recent memory.” The Open Technology Institute and Public Knowledge (OTI & PK) commented that 4.95 gigahertz of mmWave spectrum “sits, fallow, in [Carriers’] spectrum warehouses.”

Despite this, there are several future mmWave releases planned.  The United Kingdom will auction 26 and 40 GHz spectrum in early 2024.  The EU has signaled that it is seriously considering making 42 GHz available soon.  Finally, Austria, Canada, India, and New Zealand are all planning assignments in 26 or 28 GHz in the near future.

The United States is also working on future mmWave releases.  In May 2023, the FCC released a notice of inquiry (NOI) on sharing frameworks for 42-42.5 GHz.  The FCC is seeking to open 500 megahertz more mmWave spectrum.  This time, it is targeting licenses for small-sized service companies.  The NOI comment period ended in mid-September, and only eleven entities submitted comments.  While not wholly determinative, such meager engagement may exemplify a lack of interest in the band.  If this NOI progresses, the FCC will release 500 megahertz more mmWave spectrum while thousands of megahertz of existing mmWave are still under-deployed around the country.

Many commenters suggested solutions to prevent further underutilization of mmWave spectrum.  In contrast with the initial mmWave auctions, where the Commission only accesses deployment requirements after ten years, commenters supported short-term deployment requirements.  While each entity proposed slightly differing logistics for assessment and enforcement, OTI & PK, T-Mobile, and the Wireless Industry Service Providers Association (WISPA) suggested a 12-month timeframe for an operator to commence use of the license.  OTI & PK and WISPA also supported a penalty if the license goes unused after 12 months.  These commenters believe that a tight 12-month timeframe is feasible and necessary to prevent too much additional mmWave spectrum from lying fallow.

Bottom Line: MmWave Patience is Waning, and May Soon Wear Out

Across the Pacific, South Korea has lost its patience with mmWave 5G.  When operators failed to meet 10% of their build-out requirements in three years, the country revoked the licenses and began looking to resell.  This move ensured that spectrum was not going to waste and may be available for smaller operators who did not have the chance to compete in the initial auctions.

While the FCC and European regulators are not signaling anything as drastic, it is time to consider whether a slow-down in mmWave offerings is appropriate.  There is a delicate balance between making technology available and being patient.  New technologies and approaches can take years to mature.  The FCC understood this when they initially decided to forego early deployment requirements on mmWave auctions.  Also, companies like Qualcomm, an early and eager investor in mmWave, have persisted in their assessment that mmWave may still be revolutionary.  However, we should not have infinite patience or endless hope in an eventual mmWave renaissance.

Without significant mmWave momentum or deployment, and with gigahertz of unused spectrum, regulators may need to step back from mmWave offerings.  Prudent regulators should seriously consider short-term build-out requirements like those proposed in the FCC’s 42 GHz NOI.  These should be implemented and replicated worldwide in future mmWave offerings.  Additionally, regulators should focus on which emerging applications predominately use mmWave, such as FWA and crowded venues.  Crafting requirements to target these types of localized applications could also maximize the use of the spectrum and prevent further spectrum warehousing.  And eventually, it may be time for everyone to lose patience with mmWave.