CBRS (Citizens Broadband Radio Service)

Citizens Broadband Radio Service (CBRS) is a wireless spectrum band in the United States that was created by the Federal Communications Commission (FCC) to provide additional capacity for wireless networks. CBRS utilizes the 3.5 GHz frequency band, which was previously used primarily for military radar systems.

The CBRS spectrum is divided into three tiers: Priority Access License (PAL), General Authorized Access (GAA), and Incumbent Access. The PAL tier is available for commercial use and is allocated through a competitive auction process. The GAA tier is available for unlicensed use, similar to Wi-Fi, and is open to anyone who meets certain technical requirements. The Incumbent Access tier is reserved for existing government and commercial users, such as naval radar systems, and is protected from interference.

The CBRS band is managed by a shared spectrum system, which allows for efficient use of the available spectrum by dynamically allocating frequencies based on demand. This system is called the Spectrum Access System (SAS) and is responsible for managing access to the PAL tier and protecting incumbent users. The SAS works by constantly monitoring the spectrum for available frequencies and assigning them to users in real-time.

The CBRS band has a number of advantages over other wireless spectrum bands. First, it provides additional capacity for wireless networks, which is important as demand for wireless services continues to grow. Second, the shared spectrum system allows for more efficient use of the available spectrum, which reduces the likelihood of network congestion and improves network performance. Third, the GAA tier allows for unlicensed use, which can be used to provide low-cost wireless services in areas where traditional cellular networks may not be available or affordable.

The CBRS band has a wide range of potential applications. For example, it can be used to provide wireless broadband services in rural areas, where traditional wired broadband is not available or too expensive. It can also be used for industrial IoT applications, such as remote monitoring and control of machinery and equipment. In addition, the CBRS band can be used for private LTE networks in enterprise environments, such as manufacturing plants, warehouses, and hospitals.

One of the key benefits of the CBRS band is its ability to support Private LTE networks. Private LTE networks are wireless networks that are owned and operated by enterprises, rather than by traditional wireless carriers. Private LTE networks can provide several benefits over traditional Wi-Fi networks, such as higher speeds, greater capacity, and better security. Private LTE networks can also be used to support mission-critical applications, such as remote monitoring and control of machinery and equipment.

To support Private LTE networks, the CBRS band includes a feature called OnGo, which is a marketing term used by the CBRS Alliance to promote the use of the CBRS spectrum for private LTE networks. OnGo provides enterprises with access to dedicated spectrum, which can be used to create private LTE networks that are separate from the public cellular network. This allows enterprises to have greater control over their wireless network, and to customize it to meet their specific needs.

The CBRS band has been the subject of significant interest from a wide range of companies and organizations. Wireless carriers, such as Verizon and AT&T, have participated in the PAL auction and are using the spectrum to augment their existing networks. Cable companies, such as Comcast and Charter, have also expressed interest in using the spectrum to provide wireless services. In addition, a number of companies are developing equipment and services specifically for the CBRS band, including small cells, antennas, and network management software.

Despite its many benefits, the CBRS band also faces a number of challenges. One of the biggest challenges is ensuring that incumbent users are protected from interference. The SAS is responsible for managing access to the spectrum and protecting incumbent users, but there is always the risk of unintentional interference. To mitigate this risk, the FCC has established strict rules for CBRS users, including power limits, antenna height restrictions, and other technical requirements.

Another challenge facing the CBRS band is the need for additional infrastructure to support the shared spectrum system. The SAS requires a network of sensors and databases to constantly monitor the spectrum and allocate frequencies to users in real-time. This infrastructure requires significant investment, and it remains to be seen how quickly it will be deployed.

In addition, there is some uncertainty around the long-term availability of the CBRS spectrum. The FCC has only allocated the spectrum for a limited time, and it remains to be seen whether it will be renewed or made available permanently.

Despite these challenges, the CBRS band represents a significant opportunity for innovation in the wireless industry. Its shared spectrum system and support for Private LTE networks could enable a wide range of new applications and services, and its availability could help to bridge the digital divide by providing wireless broadband services in underserved areas.

Overall, CBRS represents a significant evolution in the wireless industry. Its shared spectrum system and support for Private LTE networks have the potential to transform the way we think about wireless networks, and its availability could help to address some of the key challenges facing the industry today. However, it will be important to address the challenges facing CBRS, including incumbent protection and the need for additional infrastructure, to ensure its long-term success.