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An antenna RSRP difference within 6 dB is generally considered acceptable for maintaining balanced MIMO performance and achieving expected Rank performance.

Low-band deployments mainly rely on SSB-based beam management, and CSI-RS beam management is not supported in this scenario.

Explanation
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.

The initial PRACH preamble power is calculated as:
Preamble Power = PreambleReceivedTargetPower + Path Loss
Path Loss = SSB Tx Power – RSRP
= 18 – (-90) = 108 dB
Preamble Power = -100 + 108 = 8 dBm

Explanation
According to the 5G Beamforming: An Engineer’s Overview, 32T32R and 64T64R AAUs support vertical beamforming. AAU stands for Active Antenna Unit, which is a type of antenna that integrates RF and antenna functions in one unit. Vertical beamforming is a technique that uses multiple antenna elements in a vertical array to form beams in different elevation angles. 32T32R and 64T64R AAUs have enough antenna elements to support vertical beamforming, while 8T8R and 4T4R AAUs do not have enough antenna elements to support vertical beamforming effectively.

For NR:
15 kHz → 10 slots/frame
30 kHz → 20 slots/frame
60 kHz → 40 slots/frame
120 kHz → 80 slots/frame
Thus, a 60 kHz SCS configuration contains 40 slots per radio frame.

Without CQI feedback, the gNB cannot perform link adaptation accurately. To maintain transmission reliability, it falls back to a conservative low-order MCS.

Most drive-test tools can monitor radio measurements such as RSRP, CQI, and SRS SINR, but PDSCH IBLER is generally not directly available.

An SSB consists of PSS, SSS, PBCH, and PBCH DMRS resources. The total payload associated with the occupied 20 RB resources corresponds to 864 bits.

The link budget parameters that may differ depending on use in either densely populated urban areas or rural areas are area coverage rate, shadow fading margin, and penetration loss. The area coverage rate is the percentage of area within a cell that can receive a signal above a certain threshold. In densely populated urban areas, the area coverage rate may be lower than in rural areas due to more interference and obstacles. The shadow fading margin is an additional margin added to the link budget to account for the variation of signal strength due to obstacles in the propagation path. In densely populated urban areas, there may be more buildings and structures that cause shadow fading than in rural areas, so a larger shadow fading margin may be needed. The penetration loss is the loss of signal strength when it passes through walls or windows into buildings. In densely populated urban areas, there may be more indoor users than in rural areas, so a larger penetration loss may be considered. The antenna gain is not a parameter that depends on use in either densely populated urban areas or rural areas. It is a parameter that depends on the antenna design and configuration, which are usually fixed for a given system.

Explanation
According to the HCIA-5G V2.0 Exam Outline, the statements in options A, B, and C are correct descriptions of throughput-related indicators, which correspond to options A, B, and C. The statement in option D is incorrect because adding the last small packet of each data transmission burst and its transmission duration will reduce the accuracy of throughput measurement.

Explanation
According to the 5G NR Physical Layer Specifications, demodulation reference signals (DMRSs) are required for the following channels/signals in the downlink and uplink:
Downlink Physical Broadcast Channel (DPBCH)
Downlink Physical Downlink Control Channel (DPDCCH)
Downlink Physical Shared Channel (DPOSCH)
Uplink Physical Random Access Channel (PRACH)
Uplink Physical Uplink Control Channel (PUCCH)
Uplink Physical Uplink Shared Channel (PUSCH)

Explanation
According to the 5G NR Downlink CSI Reporting, CSI-RS is the channel/signal that is used by the UE to measure and obtain the CQI. CSI-RS stands for Channel State Information Reference Signal, which is a downlink reference signal transmitted by the gNodeB to enable the UE to estimate the channel quality and feedback the CQI to the gNodeB. The CQI is an indicator of how good or bad the channel quality is, and it can be used by the gNodeB to adjust the modulation and coding scheme for data transmission.

According to the Career Certification – Huawei Enterprise , DUB8P, DUPEU, and DUMPT are boards in a base station that support CPU usage measurement, which correspond to options B, C, and D. DFAN is a fan board that does not support CPU usage measurement, which corresponds to option A.

According to the RAN3.0 feature set, TDD NR deployment supports only the Case C SSB beam pattern configuration.

Explanation
According to the 5G NR Uplink Power Control Procedure, SIB2 is the message that contains the PRACH power control parameters, such as msg3-Alpha, p0-NominalWithoutGrant, and p0-AlphaSets. These parameters are used by the UE to determine the transmit power of the PRACH preamble.

Explanation
To find the number of RBs in a 5G cell, we need to know the bandwidth and the subcarrier spacing of the cell.
The bandwidth is the total frequency range allocated for the cell, while the subcarrier spacing is the frequency separation between adjacent subcarriers in the cell. A RB is a group of 12 consecutive subcarriers in the frequency domain 12. Therefore, the number of RBs in a 5G cell can be calculated by dividing the bandwidth by the product of the subcarrier spacing and 12.
Given that the bandwidth is 100 MHz and the subcarrier spacing is 60 kHz, we can use the following formula to find the number of RBs:
Number of RBs = Bandwidth / (Subcarrier spacing * 12) Number of RBs = 100 MHz / (60 kHz * 12) Number of RBs = 100000 kHz / 720 kHz Number of RBs = 138.888…
However, since the number of RBs must be an integer, we need to round it down to the nearest multiple of
3 3. This is because the NR standard defines different frequency ranges for different subcarrier spacings, and each frequency range has a minimum and maximum number of RBs that are multiples of 3 4. For example, for subcarrier spacing of 60 kHz, the frequency range is from 24250.08 MHz to 52600.08 MHz, and the minimum and maximum number of RBs are 66 and 273, respectively.
Therefore, the closest multiple of 3 to 138.888… is 135. However, this number is not valid because it is lower than the minimum number of RBs for subcarrier spacing of 60 kHz. The next valid multiple of 3 is 273, which is also the maximum number of RBs for subcarrier spacing of 60 kHz. Therefore, the correct answer is C. 273.

Explanation
According to the 5G NR Physical Layer Specifications, Paging, SIB, and MIB are common messages that need to be scheduled. Paging is a message that is used to notify a UE of incoming data or system information when it is in idle mode or connected mode inactive state. SIB stands for System Information Block, which is a message that contains various system parameters and configuration information for UEs. MIB stands for Master Information Block, which is a message that contains essential system information such as system frame number and subcarrier spacing. These common messages need to be scheduled because they are transmitted periodically and have fixed time-frequency resources.

Explanation
According to the 5G-NR (EN-DC) Bearer Concept, in MR-DC (Multi-Radio Dual Connectivity) architecture, data split on a base station can be affected by the following factors:
PDCP layer buffer: The PDCP layer buffer stores user plane data before sending it to lower layers. The buffer size and occupancy can affect how data is split between LTE and NR bearers.
X2 latency: The X2 latency is the delay between LTE and NR base stations over the X2 interface. The X2 latency can affect how data is split between LTE and NR bearers by causing reordering or duplication of packets.
Air interface latency: The air interface latency is the delay between base stations and user equipment over the air interface. The air interface latency can affect how data is split between LTE and NR bearers by causing reordering or duplication of packets.
The RLC layer buffer does not affect data split on a base station because it is located below the PDCP layer where data split occurs.

Explanation
According to the 5G SA Cell Search & Network Entry Matrix, the first step for a UE to perform a cell search in SA networking is to synchronize frames and obtain PCI group number. This step involves the following sub-steps:
The UE scans the available frequency range to detect the presence of Synchronization Signal Blocks (SSBs) from different base stations. SSBs are periodic signals that contain essential synchronization and system information for cell search and initial access.
The UE selects an SSB with the strongest signal strength and decodes its Primary Synchronization Signal (PSS) and Secondary Synchronization Signal (SSS). The PSS and SSS are part of the SSB and provide coarse timing synchronization and cell identity information.
The UE uses the PSS and SSS information to synchronize its internal clock with that of the base station and obtain the Physical Cell Identity (PCI) group number. The PCI group number is a 9-bit value that identifies a group of 8 cells that share the same PSS and SSS sequences. The PCI group number ranges from 0 to 1007.
The other steps for a UE to perform a cell search in SA networking are:
Synchronize half-frames and obtain the ID within a PCI group: The UE further synchronizes its timing with the base station by decoding its Narrowband Synchronization Signal (NSSS), which is also part of the SSB. The NSSS provides more precise timing information and the ID within a PCI group, which is a
3-bit value that identifies a specific cell within a PCI group. The ID within a PCI group ranges from 0 to
7. By combining the PCI group number and the ID within a PCI group, the UE can obtain the full PCI, which is a 10-bit value that uniquely identifies a cell.
Obtain other cell information: The UE decodes other signals and channels in the SSB to acquire other cell information, such as system bandwidth, subcarrier spacing, frame structure, etc. These signals and channels include Demodulation Reference Signals (DMRS), Master Information Block (MIB), System Information Block (SIB), etc.
Obtain the cell signal quality: The UE measures the cell signal quality based on various indicators, such as Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ), Signal-to-Interference-plus-Noise Ratio (SINR), etc. These indicators reflect the strength, quality, and interference level of the received signal.

Explanation
The Rayce ray tracing model is a propagation model that computes propagation paths using 3-D environment geometry 3. It is based on the shooting and bouncing rays (SBR) method, which launches rays from the transmitter and traces their reflections and diffractions until they reach the receiver or are attenuated below a threshold 4. The Rayce ray tracing model offers more accurate path searching, reflection, and diffraction energy calculation for electromagnetic wave propagation than other models, such as empirical models or deterministic models 5. It also offers higher level prediction accuracy, especially for massive MIMO systems that use beamforming techniques 6. The Rayce ray tracing model is not applicable only to C-band, but also to mmWave and other frequency bands 7.