Delivering indoor connectivity has long dogged mobile network operators (MNOs). Whether it be the location of a building or the construction materials used, it is frequently difficult for mobile subscribers to get a reliable wireless signal from the MNO towers located outdoors. High-bandwidth wireless spectrum, used by many MNOs for the latest in high-speed connectivity services, does not penetrate buildings easily and has limited coverage range, leading to a mixed and frustrating experience indoors.
Over the past several years, MNOs have tackled the problem of indoor wireless connectivity by deploying distributed antenna systems (DAS) in places where large amounts of people congregate, including venues such as stadiums, convention centers, airports, major hotels, among others. Inside these facilities, the MNOs either built and operated the indoor networks themselves, or often, utilized a neutral host model, where a third-party funded, built and operated a single wireless network hosting multiple MNOs to connect the wireless customers.
While this DAS-based neutral host model worked for larger venues, the economics for smaller venues is typically too costly for MNOs, who ultimately fund the deployment of these solutions via recurring payments to the third-party neutral host operator. Attempting to apply this model downstream does not work, driving a need to find acceptable alternatives that can still be high performance and fully featured. So how do you solve this problem?
Indoor wireless solutions that come from the IT world, such as Wi-Fi, are cost efficient and familiar, and work great for more routine applications like email and web browsing, but also have known challenges when it comes to security, performance, and user mobility. Also, Wi-Fi networks, which use unlicensed spectrum, are prone to interference and service degradation when operating in crowded proximity of other Wi-Fi networks and devices.
The rapid emergence and acceptance of Citizens Band Radio Service (CBRS), with its telecom heritage, are poised to change the dynamics and economics of indoor wireless networks going forward. CBRS can be the foundation for the next-generation neutral host model that still allows an enterprise or property owner to host wireless subscribers (single or dual SIM devices) from multiple carriers on a single private CBRS network infrastructure, but with an economic model much more accommodating to buildings and enterprises of many sizes. Much of this derives from CBRS enabling a property owner or enterprise to deploy an indoor solution on their own initiative with a simpler interface to the MNOs. This means an independence from legacy cost and complexity barriers.
CBRS and the Neutral Host
Mobile traffic continues to grow, and now accounts for more than half of web traffic worldwide, Statista says. By 2022, mobile data traffic is expected to reach 77.5 exabytes per month worldwide at a compound annual growth rate of 46 percent, according to Statista. To put this in perspective, 100 people would have to search the web for 57,077 years to reach 1 exabyte of data.
The problem: With more users and smart devices being connected, the outdoor macrocell network is increasingly strained to keep up and adding more towers is rarely fast or low cost. Add to that, MNOs have focused heavily on rolling out their 5G networks and cannot afford the investment to densify or build out in-building wireless coverage across the 5M+ commercial properties out there today. The CBRS spectrum in the 3.5GHz band helps address this problem by offering more network capacity, which can be deployed indoors, where the majority of users and devices connect and where bandwidth consumption is increasingly occurring. In fact, the amount of wireless capacity CBRS offers that can now be dedicated to a single building or enterprise is on par with what a national carrier has available for a larger metro area. This presents all kinds of new opportunities to help transform both the enterprise and carrier connectivity model:
- Enterprises can cost-effectively build their own secure private 4G LTE and 5G networks, tailored to their venue, user community, and use cases while deploying a neutral host
- Access to the CBRS enterprise networks through roaming arrangements helps MNOs densify their networks, extending the coverage and capacity of their 4G and 5G networks at much friendlier cost points while offloading traffic from their existing infrastructure.
Unlike traditional licensed spectrum used by all MNOs to connect their wireless subscribers, CBRS is a shared spectrum, and can be free to use, i.e., it is not the exclusive license of a particular owner. This means anyone (property owner, municipality, enterprise) can now own and operate private cellular networks for their own needs but must follow the appropriate spectrum sharing rules which are highly standardized and automated. In addition, enterprises can deploy private cellular networks that are similar to enterprise Wi-Fi in simplicity and economics but using secure, carrier-grade LTE cellular technology, long deployed by operators around the globe. These CBRS-based private networks can be a catalyst to help change the traditional service model.
The neutral host model is not a new concept, and DAS has played out well for large venues across multiple industries where the carriers often have a clear interest in offering their service. However, a multi-carrier DAS that works well in an NFL stadium or 1 million-square-foot office building in Manhattan does not scale down particularly well for a 50,000-250,000-square-foot property and even less so for a typical enterprise, resulting in an expensive and often untenable approach for most organizations. And DAS networks require participation and investment from the carriers, who are often eager to deliver (and fund) service to a stadium, but probably less so for a 100K-square-foot suburban property or an individual enterprise in that building.
Financially, CBRS changes the game by presenting a new economic model that decouples the reliance and related cost of having to rely on the traditional MNOs to agree to make a DAS solution work. And while these are private networks, the right CBRS solution can also support seamless roaming of users across the private/public network domains. Nobody is getting stuck on a private network island.
This results in simplicity and affordability without sacrificing functionality.
These advantages have caused the industry to take note; and leading manufacturers have brought more than 80 CBRS-certified user devices to market already. CBRS is also included as part of the 5G standard, addressing any potential concern that this approach would risk the adoption of an eventual transition to 5G; CBRS is an integral part of these next-generation mobility services.
With CBRS, LTE and 5G are no longer the exclusive domain of major mobile operators. However, enterprises and property owners are not cellular operators and likely not properly equipped to design and operate a high-performance cellular network. To meet this need new types of operators are available to help them execute against this vision.
With a CBRS-based neutral host model, the cellular industry is transforming from being exclusively carrier-led to becoming enterprise-driven.