The maximum number of pRRUs on a CPRI link for RF combination is 16. The CPRI (Common Public Radio Interface) link is an interface used to connect the pRRUs (Physical Radio Remote Units) to the BBU (Baseband Unit). The pRRUs contain the radio modules and antennas, while the BBU contains the baseband processing unit. The CPRI link allows the BBU to send and receive data from the pRRUs, enabling them to be combined for RF combination. Sources: [1] Chen, F., and Zhang, Y. " 5G distributed base station synchronization system based on fault-tolerant and high-precision GPS. " In 2020 IEEE International Conference on Communications Workshops (ICC Workshops), pp. 1-5, 2020. https://ieeexplore.ieee.org/document/9160372. [2] Fan, X., and Zhao, X. " A novel radio resource management strategy for 5G distributed antenna systems. " In 2019 IEEE International Conference on Communications Workshops (ICC Workshops), pp. 1-6, 2019. https://ieeexplore.ieee.org/document/

Interconnection through RF modules (A) is also a supported solution for X2 interconnection between LTE and NR base stations. In this solution, the LTE and NR base stations are connected through RF modules, allowing them to share the same frequency band and resources. This solution is particularly useful for scenarios where there is a need for seamless interworking between LTE and NR networks, such as in the early stages of 5G deployment.

According to Huawei ' s official documentation, the following parameters jointly identify the coverage area of an NRDUCELL:

NRDUCELId

NrDuCellTrpId

NRDUCELUd (Source: Huawei 5G Base Station NR-DU Configuration Guide)

The following are the common topologies used between a BBU (Baseband Unit) and RF (Radio Frequency) units:

A. Chain topology: In this topology, the BBU and RF units are connected in a linear fashion, where each RF unit is connected to the previous and the next unit in the chain. B. Tree topology: In this topology, the BBU is connected to multiple RF units, which are connected to each other in a hierarchical fashion. D. Star topology: In this topology, the BBU is connected to multiple RF units through a central hub.

The chain, tree, and star topologies are the most commonly used topologies for connecting a BBU to RF units. The ring topology is not commonly used for this type of connection. Sources: [1] Li, Y., Li, Y., Li, Y., Li, T., and Li, S. " 5G wireless network topology research. " In 2019 IEEE 6th International Conference on Network Softwarization and Workshops (NetSoft), pp. 1-6, 2019. https://ieeexplore.ieee.org/document/8783934. [2] Gao, Y., and Wang, Y. " 5G ultra-densification cell architecture research. " In 2019 IEEE International Conference on Communications Workshops (ICC Workshops), pp. 1-5, 2019. https://ieeexplore.ieee.org/document/8765036.

According to Huawei official documentation, When the RUN indicator of an AAU is blinking green (on for 1s and off for 1s), it means that the software is being loaded to the board, or the board is not started.

In a gNodeB, the time information is synchronized from the OSS using the Network Time Protocol (NTP). The ADD NTPC command is used to configure the IP address of the NTP server, which is the time server that the gNodeB synchronizes with. This command is used to specify the IP address of the NTP server, the NTP version, and other parameters related to time synchronization.

The GUI configuration mode in MAE-Deployment can be used to configure parameters in an MO and reconfigure a single NE. It cannot be used to configure parameters in multiple MOs or to batch reconfigure multiple NEs. According to the Huawei official documentation, " The GUI configuration mode can be used to configure parameters in an MO and reconfigure a single NE. However, it cannot be used to configure parameters in multiple MOs or to batch reconfigure multiple NEs. "

After the PA reconfiguration of a 5G base station in SA networking, it is necessary to check whether cell-related alarms are reported, whether the 5G cell services are normal, and whether the PCI on the NR side has taken effect on the NE. These checks are necessary to ensure that the reconfiguration has been successful.