The Small Cell Forum (SCF) marked its 10th anniversary this week with the completion of Release 9. The release, among other things, provides a blueprint for commercializing hyperdense networks for 4G, 5G and the internet of things, while addressing the managed use of shared spectrum and the Citizens Broadband Radio Services (CBRS) band.
The theme of Release 9 is “Commercializing Hyperdense HetNets,” which looks at practical solutions to help operators transform their network capacity and performance. Updated Release 9 documents include clarified requirements for massive densification of existing networks and compares candidate architectures: distributed and centralized RAN, split RAN, cloud RAN and software defined RAN.
The section of Release 9 that addresses the CBRS 3.5 GHz band in the United States noted that it is set up to accelerate the deployment of small cells. While many barriers have previously hindered small cell growth, such as the large and costly integration between suppliers and network back-office systems, the CBRS architecture and ecosystem remove many of these constraints, making small cells more competitive and introducing significant technology advantages over Wi-Fi, according to SCF.
A key factor that can broaden the shared spectrum ecosystem is that, by default, a single radio can support all operators, the documents noted. By comparison, multiple, parallel operator-specific small cells are required in a traditional licensed small cell deployment case. In addition, CBRS can be used to provide a quality LTE layer for wireless data services in enterprise venues where the 2.4 GHz and 5 GHz spectrum bands are heavily used by Wi-Fi.
“The fact that the shared spectrum band is orthogonal to the licensed spectrum holdings of the operators simplifies deployment and management of the shared spectrum bands,” the SCF said. “This may be combined with dedicated network architecture, decoupled from operator’s core networks in a way that will simplify such deployment even further and thus contributing to new business models.”
The propagation characteristics of 3.5 GHz make the band an attractive candidate for both outdoor and indoor small cells. The FCC’s three-tier sharing paradigm is directed at incumbents, priority access license (PAL) and general authorized access (GAA) users, with indoor GAA deployments expected to occur before PAL auctions get finalized.
In the U.S., all four nationwide operators are members of the CBRS Alliance.
Verizon has said it plans to use 3.5 GHz spectrum as soon as it’s practical to do so. Verizon is actively working with multiple vendor partners and testing 3.5 GHz equipment this year in both lab and field tests.
T-Mobile USA also has plans for the 3.5 GHz space, but its executives have urged the FCC to revise the existing 3.5 GHz framework “because the current structure will not drive investment” and doesn’t align with international use of the band for 5G.