According to the  Huawei 5G Base Station Product Description , the following boards support CPU usage query:

UPEU (Universal Power and Environment Interface Unit): It provides power supply and environment monitoring functions for other boards in a subrack. It supports CPU usage query through commands or web pages.

UMPT (Universal Main Processing and Transmission Unit): It provides main processing and transmission functions for a subrack. It supports CPU usage query through commands or web pages.

UBBP (Universal Baseband Processing Unit): It provides baseband processing functions for a subrack. It supports CPU usage query through commands or web pages.

The FAN (Fan Unit) does not support CPU usage query because it does not have a CPU.

According to the  eCPRI Specification V2 , eCPRI links have the following characteristics:

They require clock synchronization: eCPRI links use Ethernet as the transport layer, which does not provide inherent synchronization. Therefore, eCPRI links require external clock synchronization methods, such as IEEE 1588v2 Precision Time Protocol (PTP) or Synchronous Ethernet (SyncE).

They are based on the IP mechanism: eCPRI links use IP as the network layer, which provides routing and addressing functions for eCPRI messages. eCPRI links can use either IPv4 or IPv6 protocols.

They require AAU support: eCPRI links connect between Radio Equipment Control (REC) and Radio Equipment (RE) in a base station. AAU (Active Antenna Unit) is a type of RE that integrates RF and antenna functions in one unit. Therefore, eCPRI links require AAU support to enable flexible functional split options and reduce fronthaul bandwidth requirements.

eCPRI links are not based on the TDM mechanism because they do not use fixed time slots to transmit data. Instead, they use variable-length packets to transmit data according to different service requirements.

According to the  HCIA-5G V2.0 Exam Outline , encryption, decryption, and integrity protection are functions of the PDCP layer, not the RRC layer. The RRC layer is responsible for radio resource management, access control, handover and mobility, among other functions.

According to the  Troubleshooting Guide for Huawei 5G Base Stations , the possible causes of SCTP link disconnection over the N2 interface are as follows:

Routes are not configured: If the routes between the base station and the core network are not configured correctly, the SCTP link cannot be established or may be disconnected.

PLMN configurations are incorrect: If the PLMN configurations on the base station and the core network do not match, the SCTP link cannot be established or may be disconnected.

Physical ports are faulty: If the physical ports on the base station or the core network are faulty, such as damaged cables, loose connectors, or port errors, the SCTP link cannot be established or may be disconnected.

The SCTP port configuration is incorrect: If the SCTP port configuration on the base station or the core network is incorrect, such as using a reserved port number or a conflicting port number, the SCTP link cannot be established or may be disconnected.

A link budget is an accounting of all the power gains and losses that a communication signal experiences in a telecommunication system  8 . A link budget can be used to determine the received signal-to-interference-plus-noise ratio (SINR), which is a measure of the quality of the signal at the receiver. The SINR demodulation threshold is the minimum SINR required to demodulate the signal successfully.  The SINR demodulation threshold depends on the modulation and coding scheme (MCS) used by the transmitter, which in turn depends on the service rate or data rate required by the application  9 . Generally, the higher the service rate, the higher the MCS level, and therefore the higher the SINR demodulation threshold. Thus, statement A is incorrect. The other statements are correct.  The interference margin is relatively small on high frequency bands because there are fewer co-channel interferers due to smaller cell sizes  10 .  The shadow fading margin is related to the edge coverage rate because it accounts for the variation of signal strength due to obstacles in the propagation path  11 .  The antenna gain of the 64T64R AAU is approximately 24 dBi according to Huawei’s product specifications  12 .

According to the  HCIA-5G - Huawei Enterprise Support Community , reflection in a large amount of water and signals traveling far along a street due to the waveguide effect are common causes of overshoot coverage, which correspond to options A and C.

According to the  Probe User Guide (V100R019C10_01) (PDF)-EN , the Probe’s BLER statistics menu provides the following statistics:

DIBLER: Downlink Initial Block Error Rate, which is the ratio of the number of erroneous downlink transport blocks to the total number of downlink transport blocks received by the UE in the first transmission.

DRBLER: Downlink Residual Block Error Rate, which is the ratio of the number of erroneous downlink transport blocks to the total number of downlink transport blocks received by the UE after all retransmissions.

Retransmission ratio: The ratio of the number of retransmitted downlink transport blocks to the total number of downlink transport blocks received by the UE.

The Probe’s BLER statistics menu does not provide the modulation scheme as a statistic. The modulation scheme is a parameter that determines the modulation and coding scheme (MCS) used for data transmission on the physical downlink shared channel (PDSCH). The modulation scheme can be QPSK, 16QAM, 64QAM, or 256QAM. The modulation scheme can be displayed on the Probe’s PDSCH configuration menu or PDSCH demodulation menu.

Therefore, the correct answer is A, B, and D.

According to the  NR-ARFCN (NR absolute radio frequency channel number) , the NR-ARFCN value consists of two components: the band indicator and the channel number. The band indicator represents the frequency band on which the carrier frequency lies, while the channel number represents the specific carrier frequency within that band. The NR-ARFCN value is calculated by the following formula:

NR-ARFCN = FREF-Offs + NREF-Offs + ΔFGlobal * (Fcarrier - FREF-Offs) / AFGIobal

where FREF-Offs is the reference frequency offset, NREF-Offs is the reference NR-ARFCN offset, ΔFGlobal is the global frequency raster, Fcarrier is the carrier frequency, and AFGIobal is the absolute frequency granularity.

Given that AFGIobal is 15 kHz, FREF-Offs is 3000 MHz, and NREF-Offs is 600000, we can plug in these values and Fcarrier = 3300 MHz into the formula and get:

NR-ARFCN = 3000 + 600000 + 5 * (3300 - 3000) / 0.015 NR-ARFCN = 633000

Therefore, the correct answer is A.