Licensed vs. Unlicensed Frequency in Street Lighting – Does it Matter? (Part 3)

Part 3: The Importance of Licensed Frequencies

In this three-part series, I have explored the critical role of communication networks in smart street lighting (Part 1) and examined unlicensed RF frequencies, their common use cases, and their potential limitations for street lighting applications (Part 2).

In this final section, I take a closer look at licensed frequencies and explain why companies like ours see clear advantages in using them for critical street lighting infrastructure.

Licensed Frequencies

Obtaining a license to operate a wireless network for narrowband applications on FCC-regulated frequencies is a straightforward process, typically involving a formal application, a fee, and a defined approval period. Once approved, the system operates on a dedicated set of frequencies that are protected by regulation. In most cases, no other wireless networks are permitted to use these frequencies within the same area.

Operating on licensed frequencies allows street lighting control networks to function on clean spectrum with minimal to no electromagnetic interference from other systems. In the rare case that interference does occur, regulatory authorities such as the FCC are responsible for resolving the issue or reallocating alternative frequencies.

Another key advantage is that licensed frequencies are specifically designated for reliable communication. This enables significantly greater transmission distances compared to unlicensed solutions. For example, a networked streetlight controller operating on licensed frequencies can transmit data over distances exceeding 15 miles.

This means that devices located many miles apart can communicate directly with a central gateway, without relying on intermediate nodes or complex network architectures. As a result, there is no need for multi-hop communication, mesh networking, or dense gateway deployment—approaches typically required when operating on unlicensed frequencies.

Simplified Infrastructure and Operational Efficiency

One of the most important practical implications of using licensed frequencies is the ability to significantly simplify network infrastructure.

In many cases, municipalities can manage their street lighting networks with a minimal number of gateways, reducing both capital investment and ongoing maintenance requirements. This streamlined architecture also reduces system complexity and improves overall network reliability.

An easy way to understand this is to compare it to wireless connectivity in everyday life. If a user could maintain a strong connection to their home Wi-Fi network across a 15-mile radius, there would be little need for cellular connectivity. Licensed spectrum-based systems achieve similar wide-area coverage—something that unlicensed solutions typically cannot provide.

Even in environments where geography or urban structure limits maximum range, solutions operating on licensed frequencies generally deliver stronger and more consistent performance.

Conclusion

Selecting the right RF frequency approach is a critical decision when deploying smart street lighting systems.

While unlicensed frequencies offer flexibility and ease of deployment, they come with inherent challenges such as interference, congestion, and variable performance. Licensed frequencies, on the other hand, provide a controlled and reliable communication environment, making them particularly well suited for mission-critical infrastructure such as public street lighting.

For municipalities and utilities seeking long-term reliability, scalability, and operational efficiency, licensed frequency solutions offer a clear and compelling advantage.

Closing

The comparison chart below highlights the strengths and weaknesses of deploying street lighting control systems using licensed frequencies versus widely deployed mesh or star networks operating on unlicensed spectrum.