The SA Standalone architecture has been a Standalone architecture that has received a lot of attention from operators and communications equipment vendors since the implementation of the R15 Phase1.2 SA freeze was completed by the 3GPP in late June 2018. Communication equipment manufacturers are actively developing SA version. After the standard freeze for only half a year, major manufacturers have launched a test version. Meanwhile, the three major domestic operators are also actively testing SA version to timely promote THE deployment of SA. The SA standard, which is popular among operators and device manufacturers, has the following advantages over the NSA (non-Standalone network) standard:
(1)SA standard is pure 5G core network architecture: since NSA standard is frozen earlier than SA standard, SA is the target network scheme, which can avoid frequent network changes under NSA network.
(2) THE SA scheme had little modification to the existing network: THE NSA, which was based on EPC+(Packet Core Internet, an evolving Packet Core network), still needed to evolve into the SA scheme, thus the network needed to be transformed for many times. The NSA scheme needs to upgrade 4G base stations to eLTE (Enhanced Long Term Evolution), which requires a large amount of upgrading and upgrading, and it is difficult to realize 4G/5G dual connection between base stations from different manufacturers.
(3)SA scheme has stronger business capability: 5G core network can support new features such as network slicing and edge computing. In the initial stage, 5G networks will mainly cover eMBB (Enhanced Mobile Broadband) hot spots, leaving 5G areas and realizing interoperability with 4G through the core network. For eMBB business, the terminal itself has a caching mechanism, so the business experience is not affected.
(4) Low terminal cost of SA scheme: The 3.5GHz band combination under NSA scheme has serious interference problem on terminal side, which will lead to high terminal cost to solve this problem. SA terminal does not involve technology such as double connection; terminal is relatively simple, low cost.
On June 6, 2019, the Ministry of Industry and Information Technology officially issued 5G licenses, marking the first year of 5G in China. SA is the target architecture, and licensed operators actively deploy SA networks for commercial use as soon as possible.
