Fixed Wireless Access – Why the interest in Licensed Spectrum?

As Fixed Wireless Access (FWA) continues to expand as a viable supplement to other broadband technologies, a key question frequently arises: which frequencies are most suitable for its deployment?

Historical Use of Frequencies in Fixed Wireless

Historically, FWA has leveraged a wide array of frequency bands. These range from those licensed for cellular technologies and fixed links like point-to-point microwave backhaul to frequencies specifically allocated for fixed wireless. Additionally, unlicensed bands such as 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz have been extensively utilized under relevant regulatory frameworks.

Innovations in Spectrum Allocation

Around the globe, innovative approaches are emerging in spectrum allocation to facilitate both large-scale national deployments and more localized, regional initiatives. Notable examples include the Citizens Broadband Radio Service (CBRS) implemented by the FCC in the United States and local or shared access licensing arrangements overseen by OFCOM in the UK. These models aim to make licensed spectrum more accessible and cost-effective for smaller providers.

Expanding Spectrum Choices

Recent years have witnessed a significant expansion in available spectrum for FWA. The 3GPP technology family (3G, 4G, 5G, and future 6G) has incorporated numerous frequency bands previously reserved for fixed links (e.g. 26 GHz, 28 GHz) or fixed wireless networks (e.g., 3.6-3.8 GHz). It has also embraced unlicensed frequencies like 5 GHz and 6 GHz. Beyond 3GPP, other technologies such as IEEE WiGig in the 60 GHz band and proprietary systems in the 3.5 GHz, 4GHz and 26/28 GHz ranges have further diversified spectrum options.

Strategic Considerations for FWA Providers

So with all the frequency options available, what should be the strategy for Fixed Wireless Access providers? Clearly, this is a complex topic… Every potential Fixed Wireless Access Provider has a different starting position.

Mobile Carriers/Operators: Mobile carriers typically deploy FWA within their existing 3GPP-compliant infrastructure, leveraging underutilized spectrum. They are also keen to expand into new frequency bands to accommodate the rapid growth in mobile data traffic across all services, not just FWA. Licensed spectrum is highly preferred for its higher power levels, extended range, and predictable performance, as it minimizes the risk of interference from other spectrum users.

Wireless Internet Service Providers (WISPs): The situation for WISPs is more complex and influenced by local regulatory access to licensed spectrum. Technology choices also play a role. If a WISP has already chosen a specific technology (e.g. for an earlier phase of deployment) then depending upon the technology they may be restricted to only a few options for new frequency bands… Technology standards such as 3GPP typically allows access to the most bands, IEEE to several bands, but proprietary technologies often come with limited hardware support and very constrained frequency options. For WISPs yet to finalize a technology platform, acquiring licensed spectrum often takes precedence over the choice of technology.

Why Licensed Spectrum Matters

To understand the appeal of licensed spectrum, you don’t have to look much further than your own home. Consider the example of home Wi-Fi, which operates on unlicensed bands (2.4 GHz, 5 GHz and now 6GHz). When connecting devices to WiFi you will have noticed a growing number of competing WiFi signals visible in your devices over the years. Over time, the proliferation of Wi-Fi networks in urban areas has led to signal congestion and interference, reducing performance predictability. Whilst WiFi access points actively try to work around this interference and select unused subfrequencies (channels), there are limits on the number of channels available, and if there are many networks in the same area interference is inevitable.

Now imagine a WISP trying to utilise the same frequency bands to provide a long distance connection to your home (and your neighbours), that connection now also using the same frequencies as your WiFi. The predictability of the WISPs service offering to your home, is now going to be impacted by the innocent activities of your neighbours e.g. expanding their WiFi coverage in their own homes.

For many years, we did see unlicensed bands being utilized for rural FWA deployments by smaller community broadband providers, often using extended-range Wi-Fi solutions. However, as the number of other users of the same spectrum has increased, and the increasing need for higher bandwidths to be delivered to the home,  the viability of such setups has diminished.

Today, when considering unlicenced spectrum and Fixed Wireless, the focus is typically on the unlicensed 60 GHz band due to a far lower number of competing frequency users. The application is typically a short-range urban deployment due to the low power levels, and path losses from the high frequencies.

Long-Term Viability and Investment

Investments in network infrastructure, whether by mobile carriers, WISPs, or government initiatives (e.g. subsidies to bridge digital divides) must consider long-term viability and return on investment. Licensed spectrum ensures predictable performance, making it a critical factor in these decisions. For instance, the U.S. government’s BEAD program has recently clarified that it mandates licensed spectrum as being a mandatory component for all FWA projects applying for rural broadband funding.

DZS: Supporting a Spectrum of Opportunities

DZS’s 3GPP-based 5G FWA devices cater to all commonly licensed frequency bands and support a range of licensing models, including national, regional, local, and shared access (e.g., CBRS). With these solutions, FWA providers can confidently navigate the complexities of spectrum strategy and deliver reliable, scalable broadband services.

Ready to boost your connectivity? Explore our innovative Fixed Wireless Access solutions, designed for high-performance across urban, suburban, and even remote rural environments. Let’s connect and transform your network today!