Things are finally looking rosier for small cells, as the technology has started to gain its long-awaited deployment momentum. Small Cell Forum said in a recent report that 2015 was a “turning point year” for the technology, with larger deployments coming online and the industry getting a better handle on deployment issues that have dogged small cell scalability.
As small cells evolve, though, there are a number of areas for future small cell development that are being examined by Small Cell Forum in order to move from the initial first wave of small cell technologies to more advanced small cells, as part of the group’s release program to support small cell technologies.
Alan Law, chair of Small Cell Forum, said that the group went through a prioritization process to bring clarity to the areas which operators wanted to see more development. Small Cell Forum is working on six areas of focus for future small cell development, including:
Enterprise. Small Cell Forum’s release program thus far has mostly focused on the business case for, and how to, deploy small cells in different environments: enterprise, rural, and residential, for example. Going forward, the group plans to put more of its energy into the deployment details for making small cells a success in various enterprise scenarios. Enterprise small cells saw a significant boost during 2015, according to numbers from Mobile Experts — 110% growth in 2015 to nearly 400,000 units. Research from iGR concluded that about 75% of large and medium U.S. businesses were aware of small cells, and as many as two-thirds of them are interested in deploying them.
Virtualization. Law said that this work area focuses on where network intelligence will reside, both in terms of mobile edge computing – more intelligence being shifted toward the edge and distributed – and in terms of architectures such as cloud-RAN, with remote heads being located separately from baseband processing. Law said that the forum is looking to advise the industry on logical separation, with an API to separate the physical layer and MAC layers in a way that could support reduced transport and latency requirements – i.e., less expensive aggregation.
In its Crossing the Chasm report, Small Cell Forum differentiated between first generation and second generation small cells in a number of areas, including that second generation small cells would include a move toward virtualization.
Use of unlicensed technologies. The move to look deeper in the aggregation of licensed and unlicensed spectrum in small cells has been pushed in part by the developments around LTE Wi-Fi aggregation or LWA; License-Assisted Access, which will be standardized in LTE Release 13 this spring, and the proprietary LTE-U technology being developed (and now, tested) by Verizon and Qualcomm, among others.
Neutral host small cells. Although there are some multi-technology small cells on offer currently, Law said, second generation small cells are expected to have multi-operator support. Small Cell Forum’s release work item has the goal of making “licensed radio small cells the preferred solution for a vertical market, multi-operator solutions” and was identified by iGR’s work as a central requirement for enterprise deployments.
Self-organizing networks and hetnets. Small Cell Forum has already been sponsoring SON plugfests to advance more automation and furthering the goal of easier small cell deployment among a heterogeneous network of macro sites, distributed antenna systems and Wi-Fi nodes. In particular, the group said in its report that “interoperable and multi-vendor SON systems are a critical enabler” and that “it will be impractical to optimize large numbers of small base stations … without a considerable degree of automation and flexibility.” While the initial path of small cell deployments focused more on the opportunistic filling of coverage and capacity gaps, the Forum expects second generation small cell deployments to be a “well-planned second layer” and very dense, which will necessitate tighter orchestration with the rest of the network.
The role of small cells in the “Internet of Things” and 5G. As 5G has gained mindshare in the telecom industry, so too has a growing awareness that for ultra-low latencies, ultra-high capacities and the utilization of very high spectrum bands for both mobile and stationary applications, small cells are expected to be central to 5G network architectures — both for human users and for IoT.
“The only way to achieve that is to densify, and so what we want to say, ‘this is what we’ve learned’ and help operators densify their networks today,” Law said.