Wi-Fi Spectrum: 6 GHz Use Is Surging and Headed Toward Exhaustion

As U.S. and global policy makers debate the future of spectrum policy, CableLabs is releasing initial results of our Wi-Fi network use analysis, which further confirms the critical need to keep the current unlicensed spectrum resources and add more soon.

In short, the 6 GHz band — the key frequency band for Wi-Fi, alongside the legacy 2.4 GHz and 5 GHz bands — is experiencing explosive growth and rapid adoption that is expected to significantly accelerate this year. As a result of the fast-paced growth of consumer data and device demands expected over the next five years, exhaustion of the 6 GHz band is quickly approaching in high-density environments.

Reallocating 6 GHz Spectrum Would Decimate Wi-Fi Connectivity

Without more unlicensed spectrum in the pipeline, full utilization of existing Wi-Fi spectrum will result in degraded performance of applications and services that rely on Wi-Fi as the workhorse of modern connectivity.

Any proposals to reduce or repurpose 6 GHz unlicensed spectrum would be devastating to Wi-Fi performance and seriously detrimental to consumers, U.S.-based device manufacturers, and other businesses that expect and depend on reliable connectivity. Failing to assign more unlicensed spectrum to support the growing use of Wi-Fi will cause consumers to experience degraded Wi-Fi performance.

These conclusions are based on a rigorous network simulation of a multi-story residential environment, using a highly capable modeling tool known as NS-3 that incorporates the specific parameters of Wi-Fi technology and user behavior. This analysis builds on CableLabs’ prior work to articulate the need for additional Wi-Fi spectrum, which we’ve explored in two recent blog posts:

• The Near Future Requires Additional Unlicensed Spectrum (February 2025)
• The Case for Additional Unlicensed Spectrum (March 2024)

This work now goes even further to model and analyze the full Wi-Fi environment in a multi-story residential building where a high number of client devices, users and networks operate in close proximity.

Specifically, the study modeled a 12-story residential building (for example, an apartment or condo building) with 12 units per floor. We included every 6 GHz Wi-Fi access point and active client device (e.g., smartphones, laptops, tablets, TVs and other connected devices) in the building. In the simulation, the full 6 GHz band is used, and specific channels and channel bandwidths were assigned to each unit randomly, while avoiding adjacent units being on the same channel. The starting point for device and traffic growth was based on a distribution of today’s typical connected homes.

The study then increased both the number of devices and peak traffic over the coming years in line with industry projections.

The Simulation in Action

To identify Wi-Fi spectrum exhaustion, the study analyzed the key indicators of latency (transmission delay) and packet loss (lost data) across every connected device in each residential unit during periods when Wi-Fi activity is highest. Latency is a strong predictor of service quality and user experience for many popular and essential applications, including real-time communications like FaceTime or Zoom, media streaming, online gaming and home security. Packet loss impairs all types of applications and is correlated with connection unreliability and congestion.

The results of the simulation show that consumers in dense residential environments are likely to experience widespread and significant Wi-Fi performance degradation, indicating near-term spectrum exhaustion based on growing demand.

In particular, the study examined the Wi-Fi performance within the 12-story residential building based on five years of growing Wi-Fi demand. In this scenario, consumers in roughly 30 percent of the simulated building experience increased one-way Wi-Fi latency — greater than 10 milliseconds (ms) — and packet loss of 2 percent or more. As latency and packet loss exceed these thresholds, the resident’s quality of experience will begin to degrade, particularly for real-time applications, such as video calling, that are most sensitive to Wi-Fi performance. As latency and packet loss further increase, even non-real-time applications, such as media streaming, will begin to fail.

Below, figures 1 and 2 are abstractions of the 144-unit building. Each rectangle represents a unit in the building. Figure 1 shows the specific units, their relative location in the building and the amount of latency for at least one 6 GHz client device in the unit after five years of growth in client devices and peak traffic. Figure 2 shows the same for packet loss. The variation in latency and packet loss across the building is a function of the complex interactions between devices within the unit and across units, varying numbers of client devices and amounts of peak traffic in various units, and the variation in Wi-Fi signal propagation and contention within and across units.

Figure 1: Latency heatmap (in five years) — 90th percentile latency, showing the units that have greater than 10 milliseconds in one-way Wi-Fi latency and the amount of latency for at least one device in those units.

Figure 2: Packet loss heatmap (in five years) — showing the units that have greater than 2 percent packet loss and the packet loss for at least one device in those units.

The initial results demonstrate how essential 6 GHz spectrum is to maintain Wi-Fi’s reliability and performance for American consumers and businesses. In addition, the findings underscore the need for policymakers to allocate more unlicensed spectrum. A failure to act would undermine the reliable Wi-Fi connectivity that enables American consumers and businesses to access high-speed broadband.

CableLabs is developing a white paper to share the detailed technical analysis summarized above, including the underlying methodology.

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