EP4655964A1

EP4655964A1 - Selecting one or more cells for a network slice in a network

Info

Publication number: EP4655964A1
Application number: EP23702765.1A
Authority: EP
Inventors: Patrick Maguire
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2023-01-27
Filing date: 2023-01-27
Publication date: 2025-12-03
Also published as: CN120584506A; WO2024156370A1

Abstract

Methods and apparatus are provided. In some examples, a method of selecting one or more cells for a network slice in a network is provided, wherein the network comprises a plurality of cells. The method comprises determining one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice. The method also comprises determining one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice.

Description

SELECTING ONE OR MORE CELLS FOR A NETWORK SLICE IN A NETWORK

Technical Field

Example embodiments of this disclosure relate to selecting one or more cells for a network slice in a network.

Background

The 3rd Generation Partnership Project (3GPP) 5th generation (5G) wireless communication services will place a broad range of throughput demands of the available radio resources in operator networks. To meet evolving service requirements, new high-band frequencies will be made available to operators to support certain service types, complementing the already deployed low-band and mid-band deployed frequency bands.

5G needs spectrum across low, mid and high spectrum bands to deliver widespread coverage and support a wide range of use cases. All three ranges have important roles to play. For example, low-bands (e.g. sub-1 GHz) support widespread coverage, including indoors, across urban, suburban and rural areas. Increased low-band capacity is required to create greater equality between urban and rural broadband connectivity and address the digital divide. Mid-bands typically offer a good mixture of coverage and capacity benefits. The majority of commercial 5G networks use mid-band spectrum within the 3.3-3.8 GHz range. Other mid-bands which may be assigned to, or repurposed by, operators for 5G networks include 1500 MHz, 1800 MHz, 2.1 GHz, 2.3 GHz and 2.6 GHz. More spectrum will be needed to maintain 5G quality of service and meet growing demand in the longer term in the mid-band, e.g. in 3.3-4.2 GHz, 4.8 GHz and 6 GHz. High-bands support the ultra-high broadband speeds envisioned for 5G (e.g. 26/28/40/66-71 GHz).

One low band (600-700MHz) capable base station can cover hundreds of square miles with a 5G service that ranges in speed from 30 to 250 megabits per second (Mbps). A mid band (2.5/3.5GHz) capable base station can cover a several-mile radius with 5G that currently ranges from 100 to 900Mbps. Lastly, a high band (e.g. millimeter wave/24-39GHz) capable base station can cover a one-mile or lower radius while delivering roughly 1-3Gbps speeds. Each of these tiers are expected to improve in performance over time.

Figure 1 illustrates an example of coverage and available bandwidth against spectrum range (i.e. frequency). It can be seen that as spectrum frequency increases, available bandwidth also increases, but range decreases. Within each frequency band, low- mid- high-, spectrum is allocated to different uses and within a given band there are multiple assignments to the same use.

Spectrum in the low-band (<2 GHz), for instance, has been licensed and used for 5G deployments in US, Canada, European Union countries, and other regions. Some of the characteristics of this spectrum include:

• Widest coverage

• Limited available bandwidth

• Better able to penetrate buildings

• Wide coverage means fewer base stations need to be deployed and so ideal in rural locations where population is smaller and return on investment might otherwise be challenging.

The mid-band is a term used to describe spectrum in the range 2 GHz to 6 GHz with 5G mid-band deployments tending to be in the range 2 GHz to 4 GHz. Examples include 2.5 GHz and C-band (3.4 - 4.2 GHz range). It provides:

• Comparable coverage to 4G and so can enable the re-use of existing cell-sites to help 5G roll-out and lower costs

• The mid-bands generally have higher available bandwidth than the low-band and so more capacity.

High-band (>6 GHz), which includes millimeter Wave (mmWave), is licensed in a growing number of countries. The high-band spectrum is of interest because of its characteristics:

• High bandwidth and so high capacity, resulting in extreme mobile broadband capabilities (very fast data rates)

• mmWaves tend to travel shorter distances and do not readily penetrate physical structures such as buildings

• In areas of high network traffic, such as urban areas, stadia and airports, operators can use higher frequency spectrum to deliver the high bandwidth necessary for the application or for the best end-user experience.

In the higher frequency bands, namely the mid- and high-bands, there tends to be more available spectrum than in the low-band. The greater availability of spectrum means that more bandwidth can be allocated and licensed for use by 5G services in given frequency ranges. More bandwidth means more capacity. For instance, channel bandwidth for a typical 4G network operating in the 2.1 GHz band (low frequency end of mid-band) may be up to 20 MHz, whereas in the mid-band frequencies around 3.5 GHz the bandwidths can be up to 100 MHz. In the high-band, say the 28 GHz band, the channel bandwidth could be up to 800 MHz (e.g. 8 x 100 MHz).

The following Table 1 summarizes the relationship between channel bandwidth and the potential throughput for the particular band.

Table 1

A network slice in a 5G wireless telecommunications network is an independent end-to-end logical network that runs on a shared physical infrastructure, capable of providing a negotiated service quality. The network slicing management functions of 5G network, such as the Network Slice Management Function (NSMF), Network Slice Subnet Management Function (NSSMF) and Communication Service Management Function (CSMF), are responsible for the end-to-end creation, management, and orchestration of network slice instances and network slice subnet instances. According to clause 6.3.3 of 3GPP TS 28.541 V18.1 .1 , a service profile for a network slice specifies the characteristics or service requirements of the network slice.

The service profile is specified in a “ServiceProfile” data type that represents the properties of the network slice related requirements that should be supported by a Networkslice instance in a 5G network. The network slice related requirements apply to a one-to-one relationship between a Network Slice Consumer (NSC) and a Network Slice Provider (NSP). A network slice can be tailored based on the specific requirements adhered to a Service Level Agreement (SLA) agreed between NSC and NSP, see clause 2 of GSMA NG.116 - Generic Network Slice Template Version 3.0 (2020-05-22). An NSP may add additional requirements not directly derived from SLAs, such as those associated with the NSP’s business goals. The Generic Network Slice Template (GST) defined by the Global System for Mobile Communications Association (GSMA) pand the service performance requirements defined in 3GPP TS 22.261 V19.0.0 and TS 22.104 may also be considered as input for the network slice related requirements. The coverage and throughput requirements of a network slice are specified as optional input parameters in a network slice service profile. These include coverageArea, dLThptPerSlice, dLThptPerUE, uLThptPerSlice and uLThptPerUE. Other optional parameters relate to capacity requirements of the network slice and include maxNumberofUEs, termDensity and activityFactor.

As part of network rollout or expansion, an operator may determine the required network capacity. While operators may have a tailored approach to determining the required network capacity, based on traffic projections it is likely that the operator will, based on the service(s) to be provided, classify/divide the overall network into service areas. The following paragraphs and table are based on 3GPP TS 22.261 V19.0.0.

The following scenarios are examples of different service areas: urban and rural areas, office and home, and special deployments (e.g. large gatherings, broadcast, residential, and highspeed vehicles). The scenarios and their performance requirements are as outlined below but will be operator and deployment specific.

• Urban macro - The general wide-area scenario in urban area

• Rural macro - The general wide-area scenario in rural area

• Indoor hotspot - The scenario for offices and homes, and residential deployments.

• Broadband access in a crowd - The scenario for very dense crowds, for example, at stadiums or concerts. In addition to a very high connection density, the users may want to share what they see and hear, putting a higher requirement on the uplink than the downlink.

• Dense urban - The scenario for pedestrian users, and users in urban vehicles, for example, in offices, city centres, shopping centres, and residential areas . The users in vehicles can be connected either directly to the network or via an on-board base station to the network.

• Broadcast-like services - The scenario for stationary users, pedestrian users, and users in vehicles, for example, in offices, city centres, shopping centres, residential areas, rural areas and in high speed trains. The passengers in vehicles can be connected either directly or via an on-board base station to the network.

• High-speed train - The scenario for users in trains. The users can be connected either directly or via an on-board base station to the network.

• High-speed vehicle - The scenario for users in road vehicles. The users can be connected either directly or via an on-board base station to the network. • Airplanes connectivity - The scenario for users in airplanes. The users can be connected either directly or via an on-board base station to the network.

The table below illustrates examples of expected parameters for a cell in each scenario.

The outcome of this operator specific process is that every cell will have an expected total capacity capability in terms of:

• Based on User Density and location of cell coverage area, the number of supported (Connected) UEs

• Based on Activity Factor, the number of Active UEs

• Based on Area Traffic Capacity, the total throughput per cell, in UL & DL directions. Performance Management features in the Operations Support Systems (OSS) node managing the network may collect performance management (PM) data on each cell and UE which may determine the current/actual traffic load (used capacity) in the cell in terms of:

• Number of connected UEs

• Number of Active UEs

• UL & DL throughput per cell

Examples of this disclosure may have certain advantages. For example, examples of this disclosure may allow for a user experience of a user using a UE connected to a network slice to be aligned with the network’s capability, capacity and the coverage requirement of the service request for the network slice. Additionally or alternatively, examples of this disclosure may avoid deployment of services that result in poor user experience and would subsequently have to be removed.

One aspect of the present disclosure provides a method of selecting one or more cells for a network slice in a network, wherein the network comprises a plurality of cells. The method comprises determining one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice. The method also comprises determining one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice.

Another aspect of the present disclosure provides apparatus for selecting one or more cells for a network slice in a network, wherein the network comprises a plurality of cells. The apparatus comprises a processor and a memory. The memory contains instructions executable by the processor such that the apparatus is operable to determine one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice, and determine one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice. An additional aspect of the present disclosure provides apparatus for selecting one or more cells for a network slice in a network, wherein the network comprises a plurality of cells. The apparatus is configured to determine one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice, and determine one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice.

Brief Description of the

For a better understanding of examples of the present disclosure, and to show more clearly how the examples may be carried into effect, reference will now be made, by way of example only, to the following drawings in which:

Figure 1 illustrates an example of coverage and available bandwidth against spectrum range;

Figure 2 is a flow chart of an example of a method of selecting one or more cells for a network slice in a network according to examples of this disclosure;

Figure 3 shows an example of a system in which examples of this disclosure may be implemented;

Figure 4 shows the system of Figure 3 including another application;

Figure 5 shows the system of Figures 3 and 4 including another application; and

Figure 6 is a schematic of an example of an apparatus for selecting one or more cells for a network slice in a network.

Detailed Description

The following sets forth specific details, such as particular embodiments or examples for purposes of explanation and not limitation. It will be appreciated by one skilled in the art that other examples may be employed apart from these specific details. In some instances, detailed descriptions of well-known methods, nodes, interfaces, circuits, and devices are omitted so as not obscure the description with unnecessary detail. Those skilled in the art will appreciate that the functions described may be implemented in one or more nodes using hardware circuitry (e.g. analog and/or discrete logic gates interconnected to perform a specialized function, Application Specific Integrated Circuits (ASICs), Programmable Logic Arrays (PLAs), etc.) and/or using software programs and data in conjunction with one or more digital microprocessors or general purpose computers. Nodes that communicate using the air interface also have suitable radio communications circuitry. Moreover, where appropriate the technology can additionally be considered to be embodied entirely within any form of computer-readable memory, such as solid-state memory, magnetic disk, or optical disk containing an appropriate set of computer instructions that would cause a processor to carry out the techniques described herein.

Hardware implementation may include or encompass, without limitation, digital signal processor (DSP) hardware, a reduced instruction set processor, hardware (e.g. digital or analogue) circuitry including but not limited to application specific integrated circuit(s) (ASIC) and/or field programmable gate array(s) (FPGA(s)), and (where appropriate) state machines capable of performing such functions.

The problem with existing solutions for selecting one or more cells for a network slice in a network, such as for example to fulfil a service request for a network slice, is that in order to determine if the network can support the service request, the combination of current network coverage and throughput capability (e.g. supported frequency bands) must be evaluated together against the input requirements from the service request on coverage and throughput. Also, the combination of current network coverage and available capacity may need to be evaluated together against the input requirements on coverage and capacity.

Some examples of this disclosure propose to evaluate the required throughput against the available throughput capability, such as for example the frequency bands supported by cells in the network, and filter out radio coverage infrastructure (e.g. cells or base stations) that are unable to satisfy the throughput requirement. Of the remaining cells, examples of this disclosure may evaluate the required throughput and coverage against the available free capacity in the required coverage area.

In a particular example, an application, referred to as “Radio Throughput Capability Resolver,” evaluates the required throughput against the throughput capability and filters out radio coverage infrastructure that is unable to satisfy the throughput requirement. Another application, referred to as “Radio Throughput Capacity Resolver,” evaluates the required throughput and coverage against the available free capacity in the required coverage area. An application “White Spot Detector” takes the filtered output from the “Radio Throughput Capacity Resolver” and determines if the remaining radio infrastructure meets the input coverage requirement.

In some examples, the Service Orchestrator in the SMO platform that executes Service Design for Service Requests (3GPP/TMF641 ) and Service Qualification Requests (TMF645) may engage an existing “Coverage Resolver” application and the above proposed applications to determine if it can satisfy the combination of the coverage and throughput requirements in a network slice service request from a radio capability perspective.

Figure 2 is a flow chart of an example of a method 200 of selecting one or more cells for a network slice in a network according to examples of this disclosure. The network comprises a plurality of cells. In some examples, the method 200 may be performed by any suitable node, such as for example a Service Management and Orchestration (SMO) node in the network or an Operations Support Systems (OSS) node in the network.

The method comprises, in step 202, determining one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice. The throughput requirement of the network slice may be specified for example by a service profile associated with the network slice (or a request for the network slice). In some examples, the throughput requirement of the network slice may be a throughput requirement for one or more User Equipments (UEs) using the network slice. Thus, in some examples, determining one or more first cells comprising at least a subset of the cells in the network in step 202 may comprise determining one or more cells that support one or more frequency bands that meet a throughput requirement for one or more UEs using the network slice. In some examples, step 202 may be performed by an application referred to as “Radio Throughput Capability Resolver” above.

Step 204 of the method 200 comprises determining one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice. Here, selected for the network slice may mean for example that the second cells form a complete list of cells that can be used by the network slice. In some examples, step 204 may be performed by an application referred to as “Radio Throughput Capacity Resolver” above. The capacity requirement of the network slice may be specified for example by a service profile associated with the network slice (or a request for the network slice). The capacity requirement may comprise one or more of the following examples: a capacity requirement of individual cells in the network slice, a number of UEs to be connected to one or more cells in the network slice, a number of active UEs in one or more cells in the network slice, an activity factor of UEs connected to one or more cells in the network slice, a throughput per UE for active UEs in the network slice, a throughput of the network slice, and/or a coverage area for the network slice.

In some examples, the frequency bands comprise a first frequency band, a second frequency band higher than the first frequency band, and a third frequency band higher than the second frequency band. The first frequency band in a cell may for example support a first throughput, while the second frequency band in a cell may support a second throughput higher than the first throughput, and the third frequency band in a cell may support a third throughput higher than the second throughput. Thus, for example, higher frequency hands may support higher throughputs than lower frequency bands.

Determining first cells comprising at least a subset of the cells in the network in step 202 may in some examples comprise, if the throughput requirement of the network slice (e.g. the throughput requirement of cells in the network) is lower than the first throughput, determining cells that support the first frequency band, cells that support the second frequency band and/or cells that support the third frequency band. Any these frequency bands should support the throughput requirement if the throughput requirement is up to the throughput of the lowest frequency band. However, if the throughput requirement of the network slice is higher than the first throughput and lower than the second throughput, cells may be determined that support the second frequency band and/or cells that support the third frequency band. Finally, if the throughput requirement of the network slice is higher than the second throughput, cells may be determined that support the third frequency band. Here, cells that are determined may be for example those that remain after other cells are filtered out, as the other cells do not support frequency bands with a high enough throughput capability. In some examples, the first frequency band comprises a frequency band below 2GHz, the second frequency band comprises a frequency band within a range 2GHz to 6GHz, and the third frequency band comprises a frequency band above 6GHz.

In some examples, the method 200 may comprise determining a coverage area of the one or more second cells, in some examples by an application “White Spot Detector” referred to above. The method 200 may also comprise, if the coverage area of the one or more second cells does not meet a coverage area requirement of the network slice, sending an indication to a consumer of the network slice and/or a provider of a service request for the network slice that the network slice cannot be provided by the network. That is, for example, there may be coverage areas requested for the network slice (e.g. in the service profile) where cells cannot be provided for the network slice, for example because the cells in those areas do not support the appropriate frequency bands, or that the cells in those areas do not have capacity to meet the capacity requirement.

In step 204, determining, from the one or more first cells, one or more second cells comprising at least a subset of the one or more first cells may in some examples comprise determining one or more second cells from the first cells that have a free capacity that meets the capacity requirement of the network slice. The free capacity of a first cell and/or a second cell may for example comprises a difference between a total capacity of the cell and a used capacity of the cell. The used capacity may in some examples be referred to as the load on the cell. The total capacity of a cell may comprise one or more of the following examples: a maximum number of UEs connected to the cell, a maximum number of active UEs in the cell, a maximum throughput of the cell, and/or a coverage area of the cell. The used capacity of a cell may comprise one or more of the following examples: a number of UEs connected to the cell, a number of active UEs in the cell, and/or a throughput of the cell.

Determining one or more second cells that have a free capacity that meets the capacity requirement of the network slice is based on a capacity policy of the network. For example, the capacity policy may identify allowed capacity overuse for one or more cells in the network. That is, for example, the “free” capacity of a cell may include the amount by which the load on the cell can exceed the total capacity of the cell.

Information identifying the total capacity of at least the one or more first cells may in some examples be received from a configuration management node in the network. Additionally or alternatively, information identifying the used capacity of at least the one or more first cells may in some examples be received from a performance management node in the network.

The method 200 may in some examples include raising an alarm or notification for one or more first cells that do not have a free capacity that meets the capacity requirement of the network slice. For example, this way an operator of the network may be informed that additional capacity may need to be added to the network in those areas or cells that do not have enough free capacity.

The following describes some particular example embodiments. In these, it is assumed that the network deployment has all three frequency bands deployed, and that the low band frequencies secure full network coverage, the mid band frequencies secure partial network coverage and the high band frequencies secure limited network coverage. Also, it may be assumed that Performance Management (PM) functions in the SMO platform are continuously monitoring the current traffic load in every cell across the network. The network, for example a SMO node in the network, may include an existing application, “Coverage Resolver,” which can determine the base stations and cells needed to satisfy a coverage requirement of a network slice. In doing so, this application determines the effective coverage area of each cell and persists it in a Configuration Management (CM) store in the network, for example in the SMO node.

Figure 3 shows an example of a system 300 in which examples of this disclosure may be implemented. The system includes a SMO platform 302 (also referred to herein as a SMO node), which may for example perform the method 200 described above. The SMO platform 302 includes CM store 304 and service orchestrator 306.

An application 308 in the system 300, referred to as “Radio Throughput Capability Resolver,” may in particular examples evaluate the required throughput (e.g. the throughput requirement of the network slice, or the cells in the slice) against the throughput capability (e.g. supported frequency bands) and filter out radio coverage infrastructure which is unable to satisfy the throughput requirement. This application may in some examples compare the throughput requirement against Table 1 above, and thus determine what filtering policy needs to be applied to the radio infrastructure coverage provided by the existing application, “Coverage Resolver,” such as for example which cells do not support the bands needed to provide the required per-UE bandwidth. As examples, if the required throughput is below 250Mbps, then no filtering needs to be applied; if the required throughput is 500Mbps, then the filtering policy should remove all “Low Band” frequency cells from the radio infrastructure coverage provided by the existing application, “Coverage Resolver”; if the required throughput is above 900Mbps, then the filtering policy should remove all “Low Band & Mid Band” frequency cells from the radio infrastructure coverage provided by the existing application, “Coverage Resolver”. It should be noted that these values and those in table 1 above are merely examples and may be different in particular networks. The application 308 provides filtered output, which is for example a list of first cells.

Figure 4 shows the system 300 of Figure 3 including another application 400, “Radio Throughput Capacity Resolver.” The application 308 is not shown in Figure 4 for clarity purposes. The application 400 evaluates the required throughput (e.g. specified by the network slice service profile), which may be the per-UE throughput in each cell in the network slice, against the free capacity on the filtered output. This application 308 will accept as input the following service capacity input requirements: maxNumberofUEs, termDensity, activityFactor, dLThptPerSlice, dLThptPerUE, uLThptPerSlice, and uLThptPerUE. As capacity calculations may in some examples be based on the maximum number of UEs in the slice, their activity factor and the UL & DL throughput per UE, it is assumed if the cumulative UE throughput requirements are met then the throughput requirements on slice level are also met.

The application 400 also reads the configured total cell capacity (e.g. used + free capacity) from the CM store 304 in SMO platform 302 for each cell specified in the filtered output. This will include but not limited to one or more of the following: Max number of Connected UEs in cell; Max number of Active UEs in cell; Max UL throughput per cell; Max DL throughput per cell; and Effective coverage area per cell. The application 308 reads the cell performance management (PM) data from PM store 402 in the SMO platform 302 for each cell specified in the filtered output from the previous step. This data will include but not limited to one or more of the following: Number of connected UEs; Number of Active UEs; and UL & DL throughput per cell. This PM data set may also in some examples be augmented or extended with additional PM insights based on output from AI/ML learning models on historical data.

The application 400 may also in some examples read capacity related policies from the Policy function 404 in SMO platform 302. This may specify allowed capacity overuse for one or more cells in the network. In particular examples, the capacity related policies may specify policies on connected UE overuse (i.e. exceeding the maximum number of connected UEs in a network, slice and/or cell), active UE overuse (i.e. exceeding the maximum number of active UEs in a network, slice and/or cell), and/or UL & DL throughput overuse (i.e. exceeding the maximum UL or DL throughput in a network, slice and/or cell).

The policies may instead or in addition specify policies on a network slice level and/or a network level. So, for example, the policies may indicate that the total capacity of the network slice or the network may be overused (i.e. potentially exceeded). In some examples, the amount by which the cell, slice or network capacity may be overused may be indicated by the policies.

The application 400 will then determine the required capacity per cell for the filtered output. For example, the input parameter termDensity in association with the calculated cell coverage of each cell may be used to determine the required number of connected UEs per cell (e.g. if termDensity is 10000 UEs/sqKm and a cell’s effective coverage area is 10sqKm, then the required number of connected UEs is 100,000). The input parameter activityFactor may be used to determine the required number of active UEs per cell, that is, a percentage of the number connected calculated by multiplying the required number of connected UEs per cell by the activityFactor. The input parameters uLThptPerUE and dLThptPerUE may be used in association with the required number of active UEs per cell to determine the required UL & DL throughput per cell, for example by multiplying the input parameters by the required number of active UEs per cell.

The application 400, “Radio Throughput Capacity Resolver,” will then calculate the available free capacity in each cell based on CM data from CM store 304 (e.g. max configured capacity) and PM data from PM store 402 (e.g. used capacity). The application may in some examples then augment the calculated free capacity in each cell based on capacity policies from Policy function 404 in SMO platform 302, e.g. may increase the available capacity in one or more cells if capacity overuse is allowed. This will be operator specific implementation in some examples. The application may then compare, per cell, the required capacity against the available free capacity, and filter out the cells which do not meet the service capacity requirement. The remaining cells may be for example the second cells referred to above.

In some examples, for cells that do not meet the capacity requirement, an alarm will be raised by SMO platform 302, so the operator is aware of the network capacity bottleneck and may take appropriate action.

Figure 5 shows the system 300 of Figures 3 and 4 including another application 500, “White Spot Detector.” The applications 308 and 400 are not shown in Figure 5 for clarity purposes. The application 500 takes the filtered output from application 400, e.g. the second cells referred to above, and determines if the remaining radio infrastructure meets the input coverage requirement. This will be an operator specific implementation.

In some examples, the Service Orchestrator 306 in the SMO platform 302 which executes Service Design for Service Requests (3GPP/TMF641) and Service Qualification Requests (TMF645) will engage the existing “Coverage Resolver” application and the applications 308, 400 and 500 to determine if it can satisfy the combination of the coverage and throughput requirement of a network slice from a radio capability and capacity perspective. Service Requests over TMF641/3GPP are requests to fulfil the service requirement, and Service Qualification Requests over TMG645 are requests to only check if the service requirements can be fulfilled. Figure 6 is a schematic of an example of an apparatus 600 for selecting one or more cells for a network slice in a network, wherein the network comprises a plurality of cells. The apparatus 600 comprises processing circuitry 602 (e.g. one or more processors) and a memory 604 in communication with the processing circuitry 602. The memory 604 contains instructions, such as computer program code 610, executable by the processing circuitry 602. The apparatus 600 also comprises an interface 606 in communication with the processing circuitry 602. Although the interface 606, processing circuitry 602 and memory 604 are shown connected in series, these may alternatively be interconnected in any other way, for example via a bus.

In one embodiment, the memory 604 contains instructions executable by the processing circuitry 602 such that the apparatus 600 is operable/configured to determine one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice; and determine one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice. In some examples, the apparatus 600 is operable/configured to carry out the method 200 described above with reference to Figure 2.

It should be noted that the above-mentioned examples illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative examples without departing from the scope of the appended statements. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim, “a” or “an” does not exclude a plurality, and a single processor or other unit may fulfil the functions of several units recited in the statements below. Where the terms, “first”, “second” etc. are used they are to be understood merely as labels for the convenient identification of a particular feature. In particular, they are not to be interpreted as describing the first or the second feature of a plurality of such features (i.e., the first or second of such features to occur in time or space) unless explicitly stated otherwise. Steps in the methods disclosed herein may be carried out in any order unless expressly otherwise stated. Any reference signs in the statements shall not be construed so as to limit their scope.

Claims

1. A method of selecting one or more cells for a network slice in a network, wherein the network comprises a plurality of cells, the method comprising: determining one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice; and determining one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice.

2. The method of claim 1 , wherein determining one or more first cells comprising at least a subset of the cells in the network comprises determining one or more cells that support one or more frequency bands that meet a throughput requirement for one or more User Equipments (UEs) using the network slice.

3. The method of claim 1 or 2, wherein the frequency bands comprise a first frequency band, a second frequency band higher than the first frequency band, and a third frequency band higher than the second frequency band.

4. The method of claim 3, wherein the first frequency band in a cell supports a first throughput, the second frequency band in a cell supports a second throughput higher than the first throughput, and the third frequency band in a cell supports a third throughput higher than the second throughput.

5. The method of claim 4, wherein determining first cells comprising at least a subset of the cells in the network comprises: if the throughput requirement of the network slice is lower than the first throughput, determining cells that support the first frequency band, cells that support the second frequency band and/or cells that support the third frequency band; if the throughput requirement of the network slice is higher than the first throughput and lower than the second throughput, determining cells that support the second frequency band and/or cells that support the third frequency band; and/or if the throughput requirement of the network slice is higher than the second throughput, determining cells that support the third frequency band.

6. The method of any of claims 3 to 5, wherein: the first frequency band comprises a frequency band below 2GHz; the second frequency band comprises a frequency band within a range 2GHz to 6GHz; and/or the third frequency band comprises a frequency band above 6GHz.

7. The method of any of claims 1 to 6, comprising determining a coverage area of the one or more second cells.

8. The method of claim 7, comprising, if the coverage area of the one or more second cells does not meet a coverage area requirement of the network slice, sending an indication to a consumer of the network slice and/or a provider of a service request for the network slice that the network slice cannot be provided by the network.

9. The method of any of any of claims 1 to 7, wherein determining, from the one or more first cells, one or more second cells comprising at least a subset of the one or more first cells comprises determining one or more second cells that have a free capacity that meets the capacity requirement of the network slice.

10. The method of claim 9, wherein the free capacity of a first cell and/or a second cell comprises a difference between a total capacity of the second cell and a used capacity of the second cell.

11 . The method of claim 9 or 10, wherein determining one or more second cells that have a free capacity that meets the capacity requirement of the network slice is based on a capacity policy of the network.

12. The method of claim 11 , wherein the capacity policy identifies allowed capacity overuse for one or more cells in the network.

13. The method of any of claims 10 to 12, comprising: receiving information identifying the total capacity of at least the one or more first cells from a configuration management node in the network; and/or receiving information identifying the used capacity of at least the one or more first cells from a performance management node in the network.

14. The method of any of claims 10 to 13, wherein the total capacity of a cell comprises one or more of: a maximum number of UEs connected to the cell; a maximum number of active UEs in the cell; a maximum throughput of the cell; and/or a coverage area of the cell.

15. The method of any of claims 10 to 14, wherein the used capacity of a cell comprises one or more of: a number of UEs connected to the cell; a number of active UEs in the cell; and/or a throughput of the cell.

16. The method of any of claims 9 to 15, comprising raising an alarm or notification for one or more first cells that do not have a free capacity that meets the capacity requirement of the network slice.

17. The method of any of claims 1 to 16, comprising determining the throughput requirement of the network slice and/or the capacity requirement of the network slice from a service profile of the network slice.

18. The method of any of claims 1 to 17, wherein the capacity requirement of the network slice comprises one or more of: a capacity requirement of individual cells in the network slice; a number of UEs to be connected to one or more cells in the network slice; a number of active UEs in one or more cells in the network slice; an activity factor of UEs connected to one or more cells in the network slice; a throughput per UE for active UEs in the network slice; a throughput of the network slice; and/or a coverage area for the network slice.

19. The method of any of claims 1 to 18, wherein the method is performed by a Service Management and Orchestration (SMO) or Operations Support Systems (OSS) node in the network.

20. A computer program comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out a method according to any of claims 1 to 19.

21 . A carrier containing a computer program according to claim 20, wherein the carrier comprises one of an electronic signal, optical signal, radio signal or computer readable storage medium.

22. A computer program product comprising non transitory computer readable media having stored thereon a computer program according to claim 20.

23. Apparatus for selecting one or more cells for a network slice in a network, wherein the network comprises a plurality of cells, the apparatus comprising a processor and a memory, the memory containing instructions executable by the processor such that the apparatus is operable to: determine one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice; and determine one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice.

24. The apparatus of claim 23, wherein the memory contains instructions executable by the processor such that the apparatus is operable to determine one or more first cells comprising at least a subset of the cells in the network by determining one or more cells that support one or more frequency bands that meet a throughput requirement for one or more User Equipments (UEs) using the network slice.

25. The apparatus of claim 1 or 2, wherein the frequency bands comprise a first frequency band, a second frequency band higher than the first frequency band, and a third frequency band higher than the second frequency band.

26. The apparatus of claim 3, wherein the first frequency band in a cell supports a first throughput, the second frequency band in a cell supports a second throughput higher than the first throughput, and the third frequency band in a cell supports a third throughput higher than the second throughput.

27. The apparatus of claim 26, wherein the memory contains instructions executable by the processor such that the apparatus is operable to determine first cells comprising at least a subset of the cells in the network by: if the throughput requirement of the network slice is lower than the first throughput, determining cells that support the first frequency band, cells that support the second frequency band and/or cells that support the third frequency band; if the throughput requirement of the network slice is higher than the first throughput and lower than the second throughput, determining cells that support the second frequency band and/or cells that support the third frequency band; and/or if the throughput requirement of the network slice is higher than the second throughput, determining cells that support the third frequency band.

28. The apparatus of any of claims 25 to 27, wherein: the first frequency band comprises a frequency band below 2GHz; the second frequency band comprises a frequency band within a range 2GHz to 6GHz; and/or the third frequency band comprises a frequency band above 6GHz.

29. The apparatus of any of claims 23 to 28, comprising determining a coverage area of the one or more second cells.

30. The apparatus of claim 29, wherein the memory contains instructions executable by the processor such that the apparatus is operable to, if the coverage area of the one or more second cells does not meet a coverage area requirement of the network slice, send an indication to a consumer of the network slice and/or a provider of a service request for the network slice that the network slice cannot be provided by the network.

31 . The apparatus of any of any of claims 1 to 7, wherein determining, from the one or more first cells, one or more second cells comprising at least a subset of the one or more first cells comprises determining one or more second cells that have a free capacity that meets the capacity requirement of the network slice.

32. The apparatus of claim 31 , wherein the free capacity of a first cell and/or a second cell comprises a difference between a total capacity of the second cell and a used capacity of the second cell.

33. The apparatus of claim 31 or 32, wherein the memory contains instructions executable by the processor such that the apparatus is operable to determine one or more second cells that have a free capacity that meets the capacity requirement of the network slice based on a capacity policy of the network.

34. The apparatus of claim 33, wherein the capacity policy identifies allowed capacity overuse for one or more cells in the network.

35. The apparatus of any of claims 32 to 34, wherein the memory contains instructions executable by the processor such that the apparatus is operable to: receive information identifying the total capacity of at least the one or more first cells from a configuration management node in the network; and/or receive information identifying the used capacity of at least the one or more first cells from a performance management node in the network.

36. The apparatus of any of claims 32 to 35, wherein the total capacity of a cell comprises one or more of: a maximum number of UEs connected to the cell; a maximum number of active UEs in the cell; a maximum throughput of the cell; and/or a coverage area of the cell.

37. The apparatus of any of claims 32 to 36, wherein the used capacity of a cell comprises one or more of: a number of UEs connected to the cell; a number of active UEs in the cell; and/or a throughput of the cell.

38. The apparatus of any of claims 31 to 37, wherein the memory contains instructions executable by the processor such that the apparatus is operable to raise an alarm or notification for one or more first cells that do not have a free capacity that meets the capacity requirement of the network slice.

39. The apparatus of any of claims 23 to 38, wherein the memory contains instructions executable by the processor such that the apparatus is operable to determine the throughput requirement of the network slice and/or the capacity requirement of the network slice from a service profile of the network slice.

40. The apparatus of any of claims 23 to 39, wherein the capacity requirement of the network slice comprises one or more of: a capacity requirement of individual cells in the network slice; a number of UEs to be connected to one or more cells in the network slice; a number of active UEs in one or more cells in the network slice; an activity factor of UEs connected to one or more cells in the network slice; a throughput per UE for active UEs in the network slice; a throughput of the network slice; and/or a coverage area for the network slice.

41 . The apparatus of any of claims 23 to 40, wherein the apparatus cokmprises or is comprised in a Service Management and Orchestration (SMO) or Operations Support Systems (OSS) node in the network.

42. Apparatus for selecting one or more cells for a network slice in a network, wherein the network comprises a plurality of cells, the apparatus configured to: determine one or more first cells comprising at least a subset of the cells in the network, wherein the one or more first cells comprise one or more cells that support one or more frequency bands that meet a throughput requirement of the network slice; and determine one or more second cells comprising at least a subset of the one or more first cells, wherein the one or more second cells comprise cells that meet a capacity requirement of the network slice, and wherein the one or more second cells are selected for the network slice.

43. The apparatus of claim 42, wherein the apparatus is configured to perform the method of any of claims 2 to 19.