Small Cells are essentially a mobile wireless installation that is smaller in scope and size than a traditional macro base station. So, why are Small Cells, which provide less coverage and necessarily are composed of equipment that may not have the full capability of macro-cells, on the rise? An important note is that the term Small Cells isn’t standardized, and at times may mean anything from slightly smaller non-traditional base stations, to distributed antenna systems (DAS), to new technology systems, like a prototype 5G base station deployment. Though there has been skepticism around Small Cells, they may be part of a solution to better provide wireless services to our world’s increasingly urbanizing population and an enabling factor in the latest evolution of mobile wireless.
Small Cells are a diverse set of technologies by nature. Typically, Small Cells are composed of the same types of equipment that supports a traditional base station, but Small Cell versions are often more integrated, lighter, smaller, lower power, and have less substantial, or more integrated, filtering to further reduce size and weight. The downscaling is necessary to fit Small Cells on the limited structures available in dense areas, such as street furniture, corner rooftops, and concealed mini-towers. The next generation of Small Cells, which will support advanced 5G technologies, will also leverage new multi-input multi-output (MIMO) antenna and beam steering technologies, as well as the non-standalone 5G new radio (NSA 5G NR) sub-6 GHz frequencies. The Small Cells used for millimeter-wave (mmWave) 5G trials and early 5G deployments coming in 2019, will also feature mmWave frequency operation, though the exact frequencies are yet to be determined by the 3GPP and spectrum regulation authorities.
Though often confused, DAS and Small Cells are different approaches to providing coverage in dense, indoor, or areas otherwise suffering from adequate coverage. Where Small Cells are fully contained and miniaturized base stations requiring their own backhaul and providing services, DAS are composed of remote antenna systems that extend the coverage of a macro-cell using transmission lines or fiber optic systems. DAS and Small Cells also differ in how they are installed and regulated. Small Cells may be a popular alternative over DAS, as Small Cells are often cheaper, and don’t require coordination with other service providers, so they can be deployed on the time frame and cost structure of a single service provider.
In a recent FCC filing, Verizon wrote, “In 2017, approximately 62% of Verizon’s wireless deployments were small cells, a figure that will only grow larger as we deploy 5G in 2018 and beyond.” With many shedding doubt on the viability of Small Cells and their adoption, it seems an interesting contrast that large wireless service providers, such as Verizon and AT&T, would herald Small Cell technologies as the current, and next, generation of their wireless deployments. The filing further stated, “Small cells are needed to meet exploding consumer demand for data, drive innovation, create new jobs, and fuel new services and capabilities such as smart communities, connected cars, smart farming, and the Internet of Things.”
Though attractive for wireless service providers who intend to reach more customers and capture/maintain their market share, Small Cells aren’t without complications. As Small Cells are new technologies, the deployments are non-traditional, and Small Cells must be set up near the trafficked areas where wireless customers like to be, the deployment characteristics for Small Cells involve many layers of regulation, zoning, siting. Many municipalities in the US don’t even have standardized processing for handling Small Cell installations, and legislation on Small Cells may currently be underdeveloped. There may also be a lack of information on the extent of this problem, as the major wireless service providers have largely been tight lipped about their Small Cell deployments. This will likely be addressed as future legislation and regulation moderates the industry in preparation of massive 5G rollouts, which will necessarily require Small Cells.
Currently, there may be some growing pains with Small Cells, as a system for deploying Small Cells isn’t yet standardized. This may slow, but will likely not prevent Small Cells being deployed, as upcoming 5G services will necessarily be deployed in Small Cells. This brings up other substantial challenges, such as installing, verifying, and maintaining the abundance of Small Cells through dense urban areas. Such an effort will require substantial amounts of portable RF test equipment, the necessary interconnect, and operators available to rapidly respond to service interruptions or regulatory issues. Moreover, the pace of Small Cell deployments will also require RF equipment providers with readily stocked components, devices, and interconnect, that are able to fulfill orders same-day and without delay.