Free Practice Questions for Huawei H35-580_V2.0 Exam

According to the Hardware Description: Bbu5900 V100r013c10, these statements are correct about the space principles for 5G BBU installation:

If the installation space is insufficient, the BBU can be installed on a wall. Ensure that the wall meets the load bearing requirements: The BBU can be installed on a wall using wall-mounted brackets. The wall must be able to bear at least four times the weight of the BBU and must be flat and vertical. The installation height of the BBU must not exceed 2 m.

If the space is greater than 600 mm, a cabinet can be added to install the BBU: The BBU can be installed in a cabinet that meets the requirements of Huawei base stations. The cabinet must have a width of 19 inches and a depth of at least 600 mm. The cabinet must also provide sufficient ventilation, grounding, and lightning protection for the BBU.

If the remaining space of an existing cabinet is greater than 4 U, the BBU can be installed directly: The BBU can be installed in an existing cabinet that has enough space for it. The BBU has a height of 2 U, so it requires at least 4 U of space in a cabinet. The existing cabinet must also meet the requirements of Huawei base stations.

The other statement is incorrect about the space principles for 5G BBU installation:

If the installation space is insufficient, install 5G boards directly into the existing 4G B8U: This statement is not supported by Huawei base stations. The 5G boards cannot be installed directly into the existing 4G B8U because they have different slot distributions and board types. The 5G boards can only be installed in a BBU5900 subrack that supports both LTE and NR modes.

According to the 5G NR Channels, the following logical channels can be mapped to different transport channels in the downlink and/or uplink:

Common Control Channel (CCCH): It can be mapped to Downlink Shared Channel (DL-SCH) or Uplink Shared Channel (UL-SCH).

Dedicated Control Channel (DCCH): It can be mapped to DL-SCH or UL-SCH.

Paging Control Channel (PCCH): It can be mapped to Paging Channel (PCH) or DL-SCH.

Broadcast Control Channel (BCCH): It can be mapped to Broadcast Channel (BCH) or DL-SCH.

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.

 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.

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 13. 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 14. 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 15. 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 16.

According to the China’s Approach to Military 5G Networks and Related Military Applications, CU-DU Split of a base station means that the base station’s control plane functions (CU) and user plane functions (DU) are separated, which can improve network flexibility and scalability.

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.

According to the BBU Quick Installation Guide (V100R005C10_04) (PDF)-EN, the UPEU in the BBU5900 needs to be connected to only one circuit breaker, not two. The UPEU is a universal power and environment interface unit that provides power supply and environment monitoring functions for other boards in a subrack. The UPEU converts -48 V DC to +12 V DC and distributes the power to other boards. The UPEU also collects alarms from the subrack and reports them to the main processing board. The UPEU can be installed in slot 0 or slot 10 of the BBU5900 subrack. The UPEU needs to be connected to a -48 V DC power cable that is connected to a circuit breaker in the cabinet. The circuit breaker must have a rated current of 16 A or higher. Therefore, the correct answer is B.

According to the 5G NR Protocol Structure Changes - An Overview, the PCFICH and PHICH channels have been deleted from the physical layer in 5G compared with LTE, because they are no longer needed due to the flexible frame structure and numerology of 5G NR.