5G RAN
V100R016C10
Capacity Management Guide
Issue
01
Date
2020-04-07
HUAWEI TECHNOLOGIES CO., LTD.
Copyright © Huawei Technologies Co., Ltd. 2020. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without prior
written consent of Huawei Technologies Co., Ltd.
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and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.
All other trademarks and trade names mentioned in this document are the property of their respective
holders.
Notice
The purchased products, services and features are stipulated by the contract made between Huawei and
the customer. All or part of the products, services and features described in this document may not be
within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements,
information, and recommendations in this document are provided "AS IS" without warranties, guarantees
or representations of any kind, either express or implied.
The information in this document is subject to change without notice. Every effort has been made in the
preparation of this document to ensure accuracy of the contents, but all statements, information, and
recommendations in this document do not constitute a warranty of any kind, express or implied.
Huawei Technologies Co., Ltd.
Address:
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Website:
https://www.huawei.com
Email:
support@huawei.com
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Contents
Contents
1 5G RAN Capacity Management Guide............................................................................... 1
1.1 Changes in 5G RAN Capacity Management Guide..................................................................................................... 2
1.2 Capacity Management Architecture and Process.........................................................................................................2
1.2.1 Capacity Management Architecture.............................................................................................................................. 2
1.2.2 Capacity Management Process....................................................................................................................................... 3
1.3 Capacity Management Stage.............................................................................................................................................. 4
1.3.1 eMBB Capacity Planning................................................................................................................................................... 5
1.3.1.1 Overview.............................................................................................................................................................................. 5
1.3.1.2 Basic Capacity Planning................................................................................................................................................. 6
1.3.1.3 xMbps Planning.................................................................................................................................................................8
1.3.1.4 Service KPIs...................................................................................................................................................................... 11
1.3.2 Dimensioning...................................................................................................................................................................... 12
1.3.3 Product Configuration......................................................................................................................................................13
1.3.4 Capacity Monitoring......................................................................................................................................................... 13
1.3.5 Capacity Optimization..................................................................................................................................................... 13
1.3.6 eMBB Network Capacity Expansion............................................................................................................................ 13
1.3.6.1 Air Interface Capacity Expansion.............................................................................................................................. 14
1.3.6.2 Device Capacity Expansion......................................................................................................................................... 18
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1 5G RAN Capacity Management Guide
5G RAN Capacity Management Guide
Overview
Capacity is an important issue throughout the network life cycle, which covers
capacity planning, network dimensioning, and product configuration during new
network construction, and capacity monitoring, optimization, and expansion
during existing network operation. This document describes 5G network capacity
management in each stage. It specifies the service range and key work at each
stage and presents the interfacing relationships among different stages. In
addition, this document introduces the basic principles of network construction
benchmarks (including basic capacity, xMbps, and service experience) and based
on these benchmarks, provides theoretical analysis of capacity expansion
benchmarks.
Product Version
The following table lists the product versions related to this document.
Product Name
Solution Version
Product Version
BTS3900/BTS5900
● 5G RAN3.1
V100R016C10
BTS3900A/BTS5900A
● SRAN16.1
BTS3900L/BTS5900L
BTS3900AL
DBS3900/DBS5900
DBS3900 LampSite/
DBS5900 LampSite
Intended Audience
This document is intended for:
●
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Field engineers
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Network planning engineers
1.1 Changes in 5G RAN Capacity Management Guide
This section describes changes in each version of this document.
1.2 Capacity Management Architecture and Process
This section describes the capacity management architecture and process.
1.3 Capacity Management Stage
This section describes capacity expansion solutions for newly deployed and
existing networks. Since 5G network deployment is still in the initial stage, this
section provides only a brief introduction to the capacity expansion solution for
existing networks and will detail the solution when existing 5G networks are
available. Both solutions aim to meet network capacity required by traffic
demands, thereby improving end user experience.
1.1 Changes in 5G RAN Capacity Management Guide
This section describes changes in each version of this document.
01 (2020-04-07)
This is the first commercial release.
Compared with Draft A (2020-01-20), this issue does not include any new topics
or changes, or exclude any topics.
Draft A (2020-01-20)
This is a draft.
Compared with Issue 01 (2019-06-06) of V100R015C10, this issue does not include
any new topics or changes, or exclude any topics.
1.2 Capacity Management Architecture and Process
This section describes the capacity management architecture and process.
1.2.1 Capacity Management Architecture
This section describes the service range and supporting documents at each stage
of capacity management.
Capacity management is involved in the new network construction stage and
existing network operation stage. These two stages are not independent of each
other. Network dimensioning and product configuration are required for network
capacity expansion to meet service requirements at the existing network operation
stage.
The following figure shows the key services and supporting documents at each
network stage.
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Figure 1-1 Capacity management
1.2.2 Capacity Management Process
This section describes the capacity management process.
The capacity management process consists of the following six stages: capacity
planning, dimensioning, product configuration, capacity monitoring, capacity
optimization, and network capacity expansion. All stages are interdependent. The
outputs of the previous stage are the inputs of the next stage, as shown in the
following figure.
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Figure 1-2 Capacity management process
1.3 Capacity Management Stage
This section describes capacity expansion solutions for newly deployed and
existing networks. Since 5G network deployment is still in the initial stage, this
section provides only a brief introduction to the capacity expansion solution for
existing networks and will detail the solution when existing 5G networks are
available. Both solutions aim to meet network capacity required by traffic
demands, thereby improving end user experience.
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1.3.1 eMBB Capacity Planning
Using LTE network capacity planning as a reference, Huawei puts forward a series
of network capacity planning solutions to better plan, build, and maintain an
Enhanced Mobile Broadband (eMBB) network featured by large bandwidth,
including basic capacity planning, xMbps planning, and service KPI planning.
1.3.1.1 Overview
To meet users' traffic demands and satisfy user experience on the network, the
network capacity needs to be planned based on operators' original requirements
(especially traffic requirements and user experience) and Huawei's recommended
solutions.
The following figure shows inputs and outputs at the capacity planning stage.
Figure 1-3 Inputs and outputs at the capacity planning stage
Huawei puts forward the following capacity planning solutions:
●
Basic capacity planning
The network capacity is planned based on the live network loads and future
capacity demands to ensure basic network KPIs (such as KPIs related to
accessibility and service drops). This solution does not consider user-perceived
rate and service experience.
●
xMbps and service KPI planning
Web page browsing and video experience cannot be evaluated based on
service KPIs. The network grid capability needs to be evaluated based on
xMbps and service KPIs to generate advice on capacity planning.
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Figure 1-4 Network capacity planning solutions
1.3.1.2 Basic Capacity Planning
Basic capacity is a common criterion for evaluating and planning network
capacity. Live network congestion can be eliminated by analyzing the network
capacity bottleneck. Future capacity demands can be planned based on the
network capacity prediction.
The following figure shows the procedure for basic capacity planning.
Figure 1-5 Procedure for basic capacity planning
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Perform the following steps to plan basic capacity at the network construction
stage:
a.
Understand operators' network construction requirements, including
traffic demands and user experience assurance solutions.
b.
Plan network construction objectives.
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c.
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Reach an agreement with operators in terms of network construction
objectives and service demands.
Perform the following steps to plan basic capacity at the network operation
stage:
a.
Evaluate the device and air interface loads on the live network to decide
the current capacity status and bottleneck. Check whether the network is
overloaded based on a certain criterion. The criterion can be resource
type-specific capacity expansion thresholds or be defined based on the
capacity load or congestion inflection curve of the live network. For
details, see 5G RAN Capacity Monitoring Guide.
b.
If the usage of a type of resource exceeds the corresponding capacity
expansion threshold, perform capacity expansion for this type of resource
and decrease the target load to 10% less than the capacity expansion
threshold. For example, if the capacity expansion threshold of the main
control board or baseband processing board is 60%, the target load
should be 50% or less. Predict the future capacity demands based on the
future traffic model and resource load growth factor.
c.
If the usage of a type of resource does not exceed the corresponding
capacity expansion threshold, predict the future capacity demands based
on the current traffic model and service load. There are various factors
causing an increase in resource load. The following parameters are
defined for predicting future capacity demands:
▪
▪
▪
▪
SubscriberFactor indicates the increase multiples of online users on
the 5G network during peak hours.
PSSigFactor indicates the increase multiples of a single user on the
PS control plane in 5G NSA networking.
TrafficFactor indicates the increase multiples of traffic on the 5G
network during peak hours.
DlSigUserThrp indicates the downlink single-user-perceived data rate
expected by operators. The rate must be determined by operators
based on actual network service demands. The default data rate is
10 Mbit/s, which can meet most 5G service demands. Determine the
access rate for WTTx users based on operators' requirements.
When predicting future capacity demands, you can specify several load
subitems for each resource type based on consumption factors, and then
sum up all load subitems after each of them is multiplied by the
corresponding growth factor to calculate the total load. You can decide
the quantities of required boards and carriers based on the target load
and board configurations on the live network.
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Figure 1-6 Capacity prediction steps
1.3.1.3 xMbps Planning
xMbps planning aims to meet the data rate required by end users. It evaluates the
data rates supported by the air interface on a grid level to decide the difference
between the current and target data rates, and then provides advice on carrier
capacity expansion and site planning by means of simulation. The access data
rates can be configured for WTTx users as required by operators to serve as the
planning target.
Mobile networks have entered the eMBB era from the voice era. In the eMBB era,
media streaming services are the leading services, and the next-stage high
definition (HD) and ultra high definition video services are taking the place of the
currently leading low definition (LD) and standard definition (SD) video services.
eMBB service user experience greatly depends on the bearer rate over the air
interface, and a high bearer rate can ensure good user experience.
xMbps Meaning
The xMbps bearer rate determines upper-layer user experience. Therefore, xMbps
should be customized during eMBB network construction based on user
experience of the target service. The customized xMbps is the minimum bearer
capability for the target service on the eMBB network and the minimum rate
guaranteed for users.
xMbps for different types of services
The bearer rate varies according to the service type. eMBB services can be
classified into web, video, Voice over Internet Protocol (VoIP), social networking,
instant message, cloud services, email, file transfer, gaming, and machine-tomachine (M2M) services. xMbps for different types of services to ensure good user
experience is shown in the following figure.
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Figure 1-7 xMbps for different types of services
User experience of a type of services needs to be evaluated in multiple
dimensions. The bearer rates to ensure good user experience may also vary
depending on the specific dimension. The highest bearer rate is selected as the
bearer rate for a type of services.
For example, the bearer rate must exceed 0.8 Mbit/s to ensure smooth video
experience for LD (360p) video services. However, at least 1 Mbit/s is required for
a short startup time at the beginning of playing a video. Therefore, 1 Mbit/s is
used as the bearer rate of LD video services. Similarly, the bearer rates of SD video
services (480p), HD video services (720p), and ultra HD video services (1080p) are
3 Mbit/s, 5 Mbit/s, and 10 Mbit/s, respectively, as listed in the following table.
Table 1-1 Bearer rates for different types of services
Format
Resolution
Code
Bit Rate
(Mbit/s)
User
Experience
Bearer Rate
(Mbit/s)
Required
Rate
(Mbit/s)
360p
480x360
H.264
0.5–0.8
Startup
Time < 4s
1
1
Interruptio
n-free
Share >
95%
0.8
Startup
Time < 4s
3
Interruptio
n-free
Share >
95%
2.3
Startup
Time < 4s
5
480p
720p
640x480
1280x720
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H.264
H.264
1.2–2.3
2.1–3.8
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Format
1080p
Resolution
1920x1080
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Code
H.264
Bit Rate
(Mbit/s)
5–7.7
User
Experience
Bearer Rate
(Mbit/s)
Interruptio
n-free
Share >
95%
3.8
Startup
Time < 4s
10
Interruptio
n-free
Share >
95%
7.7
Required
Rate
(Mbit/s)
10
The bit rates of different videos vary greatly according to video resolution. The bit rates of
videos of the same video resolution also vary greatly with the proportion of dynamic pictures,
video encoding level (profile and level), and other factors. Data in the preceding table is a
reference to the statistics of a mainstream video website.
xMbps in different areas
The distribution of eMBB services is unbalanced. High data rate services account
for a large proportion in urban areas while low data rate services are the majority
in rural areas. Therefore, high xMbps on the entire network is unnecessary.
During network construction, the values of xMbps for different areas should be
specified separately based on the mainstream services and the xMbps baseline
required for good user experience in each area.
For example, areas can be classified into major areas and common areas based on
traffic and distribution of service demands and users. During network
construction, 3 Mbit/s is used as the target bearer rate in common areas where
web services and LD video services are mainstream services and 5 Mbit/s or 10
Mbit/s is used as the target bearer rate in major areas where HD or ultra HD video
services are mainstream services. Based on the distribution of WTTx customer
premise equipment (CPE), target xMbps is determined according to operators'
requirements. Area-oriented xMbps setting saves costs and balances experience
and investment, thereby achieving maximum return on investment.
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Figure 1-8 xMbps in different areas
xMbps engineering planning
A specific xMbps anywhere and anytime is not an absolute requirement. It can be
defined as follows from the perspective of engineering planning: The xMbps is
reached in a specified percentage (typical value: 95%) of places within a specified
percentage (typical value: 90%) of time to ensure user experience of a good level
or above.
xMbps Planning Procedure
The xMbps planning procedure is as follows:
1. Deciding the target rate: A proper target rate is calculated based on the
typical rate required by services by analyzing service types and the ratio of each
type of service. 10 Mbit/s can meet 90% of service requirements on networks with
non-video services. Therefore, 10 Mbit/s is used as the target rate during xMbps
planning.
2. Evaluating grid-level rate capability: To evaluate the grid-level rate capability,
calculate the theoretical rate of each grid based on the channel quality indicator
(CQI), number of users, and available power in this grid, and then geographically
display the rates in the grids.
3. Providing advice on planning: You can provide reasonable advice on carrier
capacity expansion and site planning through simulation and positioning based on
the difference between the current grid-level rate capability and the target rate.
This method is also applicable to multi-sector planning.
1.3.1.4 Service KPIs
Service KPI planning aims to meet video service demands. The key point for the
planning is a unified evaluation standard for video service quality, reflecting user
experience. Therefore, Huawei puts forward the vMOS standard.
According to the vMOS standard, user experience of video services is scored based
on a number of factors including video source quality, initial buffering delay, and
video freeze rate. The following table lists the MOSs of the vMOS standard.
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Table 1-2 vMOS standard
MOS
Performance
Impairment
5
Excellent
Imperceptible
4
Good
Perceptible but not annoying
3
Fair
Slightly annoying
2
Poor
Annoying
1
Bad
Very annoying
vMOS is determined by the scores of sQuality, sLoading, and sStalling. sQuality,
sLoading, and sStalling indicate the video source quality, initial buffering latency,
and video freeze rate, respectively. sQuality determines the upper limit of vMOSs,
and the scores of sLoading and sStalling are related to the length of video
watching time. The longer the time is, the smaller the impact of the initial
buffering latency.
Figure 1-9 vMOS scoring standard
1.3.2 Dimensioning
At the dimensioning stage, the iterative service demands of capacity planning are
used to predict the demands of critical resources (such as air interface resources)
for network construction. These resources required at the dimensioning stage are
abstract and irrelevant to the network topology and hardware type.
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Figure 1-10 Dimensioning
For details, contact Huawei technical support engineers.
1.3.3 Product Configuration
At the product configuration stage, the abstract resource demands output from
dimensioning are used as inputs for the configuration of base stations, cells,
boards, and transport equipment based on product specifications, capability, and
other related parameters.
Figure 1-11 Product configuration stage
1.3.4 Capacity Monitoring
Major resources affecting network capacity must be monitored when a network is
running steadily. This allows for learning real-time network status and enables the
network to keep in the optimal status.
The resources to be monitored can be classified into device and air interface
resources:
●
If device resources are found to be insufficient, add devices.
●
If air interface resources are found to be insufficient, check whether capacity
optimization can relieve the congestion. Then, perform capacity expansion if
the congestion persists.
For details about resources and methods for capacity monitoring, see 5G RAN
Capacity Monitoring Guide.
1.3.5 Capacity Optimization
Capacity optimization in this section indicates capacity optimization over the air
interface. If network capacity needs to be improved to meet increasing service
demands, you are advised to perform network optimization by preference.
For details about network optimization, contact Huawei engineers.
1.3.6 eMBB Network Capacity Expansion
eMBB networks are similar to LTE networks. This section describes the eMBB
network capacity expansion method by referring to the LTE network capacity
expansion method. Network capacity needs to be expanded when it cannot meet
the capacity standard for network construction. In general, the air interface
capacity needs to meet traffic demands and the device capability needs to meet
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the air interface capacity requirement. Capacity expansion involves the air
interface and devices.
On existing networks, traffic demands are affected by network capacity. That is,
the traffic demands may be not fully reflected due to network capacity restriction.
Therefore, it is required to decide whether the traffic demands are restrained
before performing network capacity expansion.
1.3.6.1 Air Interface Capacity Expansion
This section describes the standards for air interface capacity expansion and
related solutions.
Capacity Expansion Standards
The following figure shows the relationships between the number of users and
system capacity demand, system capacity capability, actual system capacity, as
well as minimum system capacity demand in typical eMBB traffic scenarios.
●
In statistical sense, the traffic demand of each user is steady, but the capacity
demand increases with the number of users.
●
5G cells experience interference from neighboring cells. The interference
increases with the number of users covered by 5G cells, decreasing the actual
system capacity.
The actual system capacity first increases with the number of users and then
begins to decrease after the number of users reaches the maximum limit allowed
by the system capacity.
Figure 1-12 Relationships between the system capacity and the number of users
a: point at which the actual system capacity
begins to decrease
b: target minimum system capacity demand
designed by the operator
The following figure shows the relationships between the number of users and
required throughput, perceived throughput, as well as xMbps in typical eMBB
traffic scenarios.
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In statistical sense, the required throughput is basically steady in specified
traffic scenarios (relevant to user types, service types, and charging policies).
The capacity demand is not affected by the number of users.
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The perceived throughput is first steady and then begins to decrease after the
number of users reaches the maximum limit allowed by the system capacity.
Figure 1-13 Relationships between the throughput and the number of users
c: change point at which the target xMbps may or may not be reached in an area where the
network is constructed based on xMbps
Capacity expansion focuses on system capacity and user throughput. The capacity
expansion standard for the air interface is listed in the following table.
Dimension
Standard
System capacity
The actual system capacity has
reached the point at which the
capacity starts to decrease (point a in
Figure 1-12).
The actual system capacity has
dropped below the target minimum
system capacity demand (indicated by
point b in Figure 1-12).
User throughput
Target xMbps (point c in Figure 1-13)
Capacity Expansion Solutions
Adding carriers
Operators usually deploy only one carrier during initial network construction. As
the number of users increases, the capacity of a single carrier will gradually
become limited. In densely populated urban areas, traffic on networks is heavy
and it is likely that the capacity of hotspot cells becomes limited.
Adding carriers is the most desirable method for capacity expansion because this
method does not affect live networks and almost requires no additional
equipment.
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This capacity expansion method is applicable when the number of users reaches
the allowed maximum or the throughput is limited due to capacity insufficiency.
Add carriers when the following conditions are met:
●
A second carrier is available.
●
The signaling load is light.
For detailed operations, see 5G RAN Reconfiguration Guide.
● After carriers are added, new cells and their neighboring cells (existing cells) are working in
different frequencies. Therefore, inter-frequency handover parameters must be properly
configured to ensure successful inter-frequency handovers. In this way, adding carriers will
not cause handover performance to deteriorate.
● For example, you can enable inter-frequency load balancing to ensure even load distribution
on multiple carriers.
● The inter-frequency handover policies and related parameter settings are complicated. For
details, see Mobility Management Feature Parameter Description.
Adding gNodeBs
You can add intra-frequency and inter-frequency gNodeBs for small-scale capacity
expansion. Adding intra-frequency gNodeBs is more common due to carrier and
networking restrictions.
●
Adding intra-frequency gNodeBs
In some hotspot areas, adding intra-frequency gNodeBs improves the capacity in
these areas, but it also causes interference, which affects the coverage of existing
cells. Therefore, you need to optimize RF and network parameters after adding
intra-frequency gNodeBs so that the addition has less negative impact on the live
networks.
This capacity expansion method is applicable when coverage holes exist, the
number of users reaches the maximum limit, or the throughput is limited due to
capacity insufficiency. Add intra-frequency gNodeBs when the following conditions
are met:
●
A second carrier is unavailable but a new site can be acquired.
●
The interference from newly added intra-frequency gNodeBs is controllable
and has little impact on live networks.
●
Emergency communications are required at places where the traffic volume
surges, for example, railway stations during holidays and stadiums with major
events.
There is a rare scenario where intra-frequency gNodeBs are added at the existing
site to serve some cells of the existing gNodeB. This solution can only be used
when the high load on the existing gNodeB cannot be relieved after a main
control board of higher specifications is installed in the existing gNodeB. For
example, if an existing gNodeB serves cell 0, cell 1 and cell 2 and the number of
users in cell 0 is the largest among the three cells, a new gNodeB can be added.
You can connect the main control board in the existing gNodeB to the RF module
of cell 0 and connect the main control board of the new gNodeB to the RF
modules of cell 1 and cell 2. This method does not require cell addition or RF
parameter optimization.
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Adding inter-frequency gNodeBs
Adding inter-frequency gNodeBs is preferred for capacity expansion if carriers are
sufficient. Unlike capacity expansion through adding intra-frequency gNodeBs,
adding inter-frequency gNodeBs does not cause intra-frequency interference.
Theoretically, adding inter-frequency gNodeBs doubles cell capacity.
This capacity expansion method is applicable when the number of users reaches
the maximum or the throughput is limited due to capacity insufficiency. Add interfrequency gNodeBs when the following conditions are met:
●
A second carrier is available.
●
New sites can be acquired. In this case, inter-frequency gNodeBs can be added
at different coverage areas.
●
The signaling overheads and the number of users in the existing gNodeB have
reached the upper limits, and capacity expansion cannot be achieved by
adding inter-frequency cells.
Both adding inter-frequency gNodeBs at different coverage areas and adding
inter-frequency co-coverage gNodeBs are supported.
Since inter-frequency handovers will occur between the added inter-frequency
cells and their neighboring cells, you need to optimize RF and handover
parameters. For details, see Mobility Management Feature Parameter Description.
For details on data configuration for new base stations, see 3900 & 5900 Series
Base Station Initial Configuration Guide.
For details on hardware installation for new gNodeBs, see related installation
guides.
Splitting sectors
In sector splitting, sectors with narrow beam antennas are added to shrink the
coverage areas of individual sectors. Currently, sector splitting can be implemented
either by splitting an omnidirectional sector into three sectors or splitting three
sectors into six sectors.
The total capacity of an gNodeB increases with the number of sectors. However,
the increase is not linear for the following reasons: There is a certain amount of
radiation beyond the lobe width, which causes interference to adjacent sectors.
Adjacent sectors also have coverage overlaps. The larger the number of sectors,
the larger the number of handover areas. As a result, handover overheads increase
and channel quality in handover areas decreases, causing the throughput in
individual sectors to decrease.
To control inter-cell interference, ensure that the following requirements are met:
●
Antennas should not directly face each other to decrease interference
between neighboring cells.
●
The reference signal power should be decreased to avoid overshoot coverage
because areas covered by cells are reduced after the splitting.
This capacity expansion method is applicable when the number of users reaches
the allowed maximum or the throughput is limited due to capacity insufficiency.
Split sectors when the following conditions are met:
●
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New carriers are unavailable.
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New sites cannot be obtained.
Sector splitting involves installing antennas and adding cells. For details, see
related installation guides and 5G RAN Reconfiguration Guide.
1.3.6.2 Device Capacity Expansion
Device capacity expansion must match the demands for air interface capacity.
Theoretically, if the system resource usage is measured on an extremely small
percentage (such as 1%) basis, capacity expansion can be performed based on
network tolerance levels for the resource insufficiency ratio. For example, capacity
expansion is recommended for networks requiring a low device resource
insufficiency ratio when the probability of resource usage higher than 90%
exceeds a certain percentage (such as 5%). Capacity expansion is recommended
for networks tolerant of a high device resource insufficiency ratio when the
probability of resource usage higher than 99% exceeds a certain percentage (such
as 5%).
The actual granularity for measuring resource usage cannot be as small as the
theoretical granularity. Only the average resource usage and maximum resource
usage on the live network are available for determining whether to expand the
system capacity. Considering the fluctuation in actual service demands, the
measurement granularity is selected based on the statistical data obtained during
peak hours. The peak-to-average ratio should also be considered to decrease the
probability that device resources are insufficient.
For the capacity expansion thresholds for device resources, see 5G RAN Capacity
Monitoring Guide. The thresholds are the recommended values provided by
Huawei based on empirical network data and may be adjusted according to
related experience and information.
Capacity Expansion Solutions
Device capability includes hardware, which must be considered when device
capacity expansion is performed as required by air interface capacity expansion.
Board specifications include items such as user number and signaling processing
capability. If an item reaches the specified threshold, replace existing boards or
add new boards to expand capacity.
Device capacity expansion methods vary with scenarios as follows:
●
Replace the board when a new board with better performance is available.
●
Add a baseband processing board when the main control board can bear
additional load but the load on the existing baseband processing board
reaches the threshold.
The board to be replaced can either be a main control board or a baseband
processing board.
If radio resources are sufficient after a baseband processing board is added, the
cell with heaviest load on the original baseband processing board is established on
the new baseband processing board, and the rest cells remain on the original
baseband processing board.
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5G RAN
Capacity Management Guide
1 5G RAN Capacity Management Guide
If a gNodeB has been configured with multiple baseband processing boards and
one of the baseband processing boards is overloaded, cells on this baseband
processing board are reestablished on lightly loaded baseband processing boards.
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