Research and Innovation Action

5G-Enhance
5G Enhanced Mobile Broadband Access Networks in
Crowded Environments

D4.1 Title: Report on requirements of ASNRM architecture
Contractual Delivery Date:

M4 (31.10.2018)

Actual Delivery Date:2018-10-31

Work Package

WP4

Responsible Beneficiary:

FOKUS

Contributing Beneficiaries:

NICT, TUAT, UEC, UOULU, FOKUS

Dissemination Level:

PublicVersion:

1.0

This project has received funding from the European Union’s Horizon 2020 research andinnovation programme under grant agreement No 815056.
PROPRIETARY RIGHTS STATEMENT

This document contains information, which is proprietary to the 5G-Enhance Consortium.

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PROPRIETARY RIGHTS STATEMENT

This document contains information, which is proprietary to the 5G-Enhance Consortium.

Document ID: WP4 / D4.1

Document Information
Document ID:
Version Date:
Total Number of Pages:
Abstract:

D4.1
26This document presents the 5G-Enhance WP3 scope. It
outlines the network and spectrum sharing technologies as
defined by 3GPP and its enhancements plannend in thisProject.

Keywords:

Authors
Full Name

Beneficiary /Organisatione-mailRole

Bjoern Riemer

FOKUS

bjoern.riemer@fokus.fraunhofer.deOverall Editor

Marius Corici

FOKUS

Contributor

Marja Matinmikko-Blue

UOULU

mariusiulian.corici@fokus.fraunhofer.deMarja.Matinmikko@oulu.fi

Stanislav Filin

NICT

sfilin@nict.go.jp

Section Editor

Takeo Fujii

UEC

fujii@awcc.uec.ac.jp

Contributor

Satya K. Joshi

UOULU

satya.joshi@oulu.fi

Contributor

Kenta Umebayashi

TUAT

ume_k@cc.tuat.ac.jp

Contributor

Contributor

Reviewers
Full Name

Beneficiary /Organisatione-mailRole

Haesik Kim

VTTHaesik.kim@vtt.fi

Reviewer

Version history
Version

Date

Comments

0.1
0.5
0.8
0.9
1.0

2018-07-31
2018-08-30
2018-10-01
2018-10-20
2018-10-29

Initial TOC and Structure
Merged Contens for Section 2 and 4
Introduction, final inputs for section 5 and 6
Editioral work, references
Final internally reviewed Version

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Executive Summary
One of 5G Enhance main objectives is the advanced Spectrum and Network sharing for eMBB
in dense areas. The objective of this deliverable is to define the technological roadmap of WP4,
which focuses on the development of advanced spectrum and network sharing techniques tobe used in dense areas. This document presents the state of the art in sharing technologires
as defined by the 3GPP and how this can be enhanced to further advance the sharing
technologies for eMBB and in conjunction with micro operators.

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Table of Contents
1.

Introduction ....................................................................................................... 8

2.

State of the art in spectrum and network sharing .......................................... 9
2.1
2.2

3.

Motivation for sharing ..........................................................................................9
Sharing architectures .........................................................................................10

5G system architecture ................................................................................... 14
3.1
3.2

Architecture and functions.................................................................................14
5G technologies and concepts ..........................................................................15

4.

Micro operator scenario in dense environments providing eMBB ............. 17

5.

New requirements to realize micro operator scenario (for eMBB) .............. 20
5.1
5.2
5.3

Network Sharing (CN) requirements ..................................................................20
Spectrum sharing requirements ........................................................................21
Possible technologies/directions to satisfy requirements ...............................21

6. 5G Architecture and functional enhancements for micro operator supportof eMBB ................................................................................................................... 23
6.1
6.2

7.

Spectrum Sharing ...............................................................................................23
Network Sharing .................................................................................................24

Summary .......................................................................................................... 25

References .............................................................................................................. 26

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List of Acronyms and Abbreviations
Term

Description

5G

Fifth Generation

ASNRM
LSA
SAS
eMBB

Advanced Spectrum and Network Resouce Managemen
licensed shared access
spectrum access system
Enhanced Mobile Broad Band

List of Definitions
Spectrum and Network Sharing - a technology that enables multiple operators to share same
set of radio resources (spectrum) and/or some parts of a network including RAN and/or CN.

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1.Introduction
This is the first deliverable of the 5G Enhance WP4: Advanced Spectrum and Network
Resouce Management (ASNRM) which handles the mechanisms and technologies required
for the sharing of the different resouces between different use cases, including the sharing of
the spectrum, base stations and core network.
The role of this deliverable is to define a network sharing architecture, able to provide the basis
for the further developments as well as to determine the general technical direction of theresearch and innovation work within the work package.
As being the first deliverable of the work package, it includes the preliminary work required
from the partners in order to bring together the prior knowledge within a common
understanding and system. For this, a comprehensive and condensed state of the art inspectrum and network sharing was performed (Section 2). As basis of the 5G-Enhance, thenetwork sharing is considered as the best alternative of deploying parallel use cases on top of
high-end equipment to address the stringent requirements of enhanced Mobile Broadband(eMBB) use cases. Three levels of sharing were identified: at spectrum level, at radio accessnetwork (RAN) level and at Core Network (CN) / Architectural level. The RAN and the core
network sharing are made possible by the sharing of underlying hardware resouces
represented by compute, storage and network.
Ads part of the initial state of the art, a comprehensive architecture of spectrum and resource
sharing is defined, following the 3GPP 5G architecture (Section 3). This architecture has therole to concentrate the developments within the project towards a common understanding of
the partners. Additionally, by comparing it to the standards, it gives the opportunity to underline
the missing critical technology elements towards which the rest of this work package will bedirected to.
Following the proposed architecture, a set of considerations are made towards its proper
deployment within the main use case of this work package: the micro-operator providing eMBB
communication (Section 4). These considerations further the architecture on the direction of
the interaction with the User Equipment (UE) required as well as on the split of the functionality
between the local micro-operator and the central locations.
A new set of requirements derived from the developed architecture are arising, specificallyoriented towards handling the split between the local and the remote location and the spectrum
allocation (Section 5).
This deliverable concludes with a section which underlines the specific architecturalenhancements towars which this work package will work (Section 6), enabling the focusing of
the work towards a meaningful direction.

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2. State of the art in spectrum and network sharing
This section describes the state of the art in spectrum and network sharing in relation to the
5G system, the eMBB use case and the dense communication environments.
2.1 Motivation for sharing
Spectrum and network sharing are representing a set of technologies that allows several
operators to share same spectrum, RAN or CN. In one form or another this technology has
been present in 3G and 4G systems since Release 6 of 3GPP specifications [TS 23.251].
The key motivation for network sharing by conventional operators has been reduction of
deployment and maintenance cost. Various sharing scenarios are described in [TR 22.951],
for example:· Different CNs share same RAN elements without spectrum sharing, i.e., using different
frequencies· Different CNs share RAN of a third-party operator, where spectrum resources used but
different CNs are not separated· Different operators share same spectrum without sharing RAN or CN· Different RANs share same CN or some part of it.
Above scenarios could be implemented based on operator needs and available radio
regulations.
Compared to 3G and 4G, where one system was designed to enable all intended use cases,
5G system enables diversified deployments, where some parts of the system are designed forspecific use cases. Furthermore, due to the specific spectrum and usage regulations, in someregions of the world (e.g. Germany) there is the possibility to deploy private 5G networks within
the specific use case location and to share these networks with other private or public
operators.
ITU has developed requirements and roadmap towards IMT-2020. These requirements are
the result of analyzing various current and potential future applications. It is important to notethat not all requirements shall be satisfied simultaneously. Instead, three key groups of use
cases could be identified:· Enhanced mobile broadband (eMBB): focused on supporting high data rate users [TR22.863]· Massive machine type communication (mMTC): focused on supporting large number oflow data rate users and on energy efficiency of communication [TR 22.861]· Ultra reliable low latency communication (URLLC): focused on providing high reliability andlow delay [TR 22.862].
Especially towards addressing eMBB and URLLC, there is a strong need to have high-end
technologies being deployed close to the location of the subscribers in order to be able toprovide the extra capacity required as well as the low latency and the reliability of thecommunication. This extends the current centralized network model, where a uniform operator
is deployed across a country, towards a more granular set of deployments, where local microoperators (which could also be part of a wide area operator) provide enhanced services in a
specific location for the specific use case need.
As a result, there could be deployments, including RAN and CN, tailored to a specific group of
use cases or even a subgroup within, for example, eMBB and URLLC group of use cases andaddressing the specific deployment requirements for example enterprise networks withinbuildings or public networks in airports or train stations.
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In such situation, where there is a need to deploy multiple RANs and/or CNs for different users
even at the same geographical area the importance of spectrum and network sharing grows
considerably. This is multiplied by the need of high end of the 5G technologies to be able tosupply the response to the specific capacity, delay and reliability requirments, ultimately
resulting in very high costs. Because of these reasons, network sharing was included in thebaseline Release 15 of 5GS System Architecture [TS 23.501].
This also brings the concept of micro operator in play. In this concept a third-party could deploy
a system within a localized area tailored to the users in this area. While system could be 5Gbased or non-5G-based, it could allow users of public 5G networks to access some services
to help realize some of the 5G use cases subject to service agreements between a micro
operator and public 5G operators.
For example, instead of deploying dedicated parts of each of several public operators in a
specific geographic location (e.g. train station) and inquiring high costs for such deployment
and maintainance, private operator network could be deployed and some part of its capacity
could be shared with these public operators.
To summarize, motivation for spectrum and network sharing is as follows:· Reduction of deployment and maintenance cost for public operators by using RAN and CN
resources of shared networks· Creating new business models and opportunities for competition and service level
improvements by enabling micro-operator deployment scenarios· Improving spectrum utilization efficiency by using various spectrum sharing technologies.
2.2 Sharing architectures
Which resources are shared depends on sharing scenarios, operator agreements, andavailable radio regulations.
In 3G and 4G two basic spectrum and network sharing architectures have been standardized[TS 23.251]:· Gateway Core Network (GWCN)· Multi-Operator Core Network (MOCN).
GWCN is shown in Figure 1. In this configuration not only RAN but also some elements of CN
are shared.

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CN......... Operator
A

SharedMSC/SGSN

CN
Operator B

CN
Operator C

SharedMSC/SGSN

SharedMSC/SGSN.........

Iu

RNC

RNC

RNC

Radio Access Network
Operator X

Figure 1 GWCN network sharing configuration [TS 23.251]
MOCN is shown in Figure 2. In this configuration multiple CNs are connected to shared RAN.

.........

CN
Operator A

CN
Operator B

CN
Operator C.........

Iu

RNC
Radio Access Network
Operator X

Figure 2 MOCN network sharing configuration [TS 23.251]
In both configurations spectrum could be shared or not depending on how RAN allocates radio
resources.
In Release 15 of 5GS only 5G MOCN configuration is specified as shown in Figure 3. In thisconfiguration multiple 5G CNs are connected to the same NG-RAN.

.........

5GC
Operator A

5GC
Operator B

5GC
Operator C.........

N2/N3

NG RANRadio Access Network
Operator X

Figure 3 5G MOCN network sharing configuration [TS 23.501]

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In all these network sharing architectures PLMN IDs of participating operators are broadcasted
within the service area of the shared RAN and an UE can select any of these PLMNs if it hascorresponding subscription.
In 5G wireless network, as in any wireless system, spectrum resource is limited andtechnologies to improve spectrum utilization are important. Spectrum sharing is one of suchtechnologies. Several spectrum sharing approaches, such as LSA (licensed shared access)and SAS (spectrum access system) have been proposed in [Tehrani et al. 2016].
In LSA, spectrum is shared by an incumbent wireless system and another wireless system thatis allowed to use this spectrum on a non-interference basis under the specific radio regulations.
LSA provides mechanisms for protecting the incumbent spectrum users and introduces
additional licensed users in the given band resulting in quality guarantees for both entrant andincumbent systems. It does not currently define how the additional licenses are defined andawarded as this is a national matter decided by the national regulators. The three-tier model
for Citizens Broadband Radio Service (CBRS) allows MNOs and other new small scale
entrants to operate on local spectrum licenses called Priority Access Licenses (PAL) in specificareas called census tracts where the license holder defines a protection area where its
operation has guaranteed quality. Spectrum sharing in the model id implemented via Spectrum
Access System (SAS) which is defined by FCC and three tires of spectrum users are specified:· the first tier is incumbent user,· the second tier is priority access license (PAL) user and· the third tier is general authoriezed access (GAA) user which has lower accessguarantees than the PAL.
Local spectrum availability is critical for the establishment of micro operator networks which
can be accomplished through spectrum sharing. Figure 4 illustrates the high-level architecturefrom [Matinmikko-Blue et al. 2018] for micro licensing where the regulator defines the sharing
rules for local spectrum micro licenses. If there are incumbent spectrum users, they areprotected from harmful interference from the micro operators. The micro operator has a
network management system with spectrum manager that controls its spectrum accessaccording to spectrum availability information through spectrum repository and co-existence
manager. The co-existence manager is a new entity to coordinate between different license
holders including incumbents and micro licensees with different levels of spectrum accessrights.

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Figure 4 High-level architecture for micro operator concept with micro licensing(modified from [Matinmikko-Blue et al. 2018]).

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3.5G system architectureThis section will describe 5G system architecture based on a set of TSs. Description will
include Architecture and Functions. Also, new technologies and concepts compared to 4G
system will be briefly described here. This is also state of the art as in Section 2. Compared to
Section 2, where CN was one block, in Section 3 details of 5G System Architecture areprovided. The description will be based on 5G Release 15 that will serve as a baseline to add
new features to be developed during this project.
3.1 Architecture and functions
Baseline 5G architecture has been defined by 3GPP in Release 15 and described in [TS23.501], including procedure description [TS 23.502] and policy framework [TS 23.503]. This
5G System Architecture is shown in Figure 5.

NSSF
Nnssf

NEF

NRF
Nnrf

Nausf

Namf

AUSF

SMF

AMF

(R)AN

Naf

Nsmf

N4

N2

UE

AF

Nudm

Npcf

Nnef

UDM

PCF

N3

UPF

N6

DN

Figure 5 5G System Architecture [TS 23.501]

The 5G System Architecture consists of the following network functions (NF), which are briefly
described in this section (for the full information please check the 3GPP specification[TS23.501]· User Equipment (UE) – an end user terminal able to obtain services from 5G system using
RAN.
· (Radio) Access Network ((R)AN) – an access network in a 5G system, typically directly
associated with the 5G radio base stations.
· Authentication Server Function (AUSF) – a network function that handles theauthentication of UEs.
· Access and Mobility Management Function (AMF) – a network functionthat handles access
control and mobility management of the UEs.
· Session Management Function (SMF) – a network function that handles session
management.
· Unified Data Management (UDM) – a structured data base including the subscription profile
for the UEs.
· NF Repository Function (NRF) – the NRF enables the discovery and the dynamic
notifications on the status of the communicating network functions.
· Network Exposure Function (NEF) – a generic exposure function which includes all thecontrol plane APIs available towards the applications.

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·
·
·
·

Network Slice Selection Function (NSSF) – a network function which enables the selectionof a slice of network functions for a particular data flow from an application.
Policy Control Function (PCF) – a network function making decisions on QoS and charging
policies for specific applications.
Application Function (AF) – a network functions that enables an application to influence
how its traffic will be handled (e.g. routed).
Data Network (DN) – a generic name for the system towards and from which the packet
core receives the data from (e.g. the Internet).

Figure 5 shows baseline 5G System Architecture. [TS 23.501] also describes how this systemarchitecture is applied to non-roaming scenario with single and multi-PDU connections, homerouted and local-breakout roaming scenatios, support of non-3GPP access and interworking
with EPC.
Detailed description of 5G System Architecture NFs is presented in [TS 23.501], interactions
between NFs are described in [TS 23.502] and will be defined is further detailes by 3GPP CT
groups, policy and charging framework is defined in [TS 23.503]. Instead of repeating all thisinformation in this deliverable, we highlight what new technologies and concepts are included
in 5G System.
3.2 5G technologies and concepts
5G System Architecture enables deployment of such new technologies as Network Function
Virtualization and Software Defined Networking. In this section, the new key concepts
considered are described.
Some of the key concept used in 5G System Architecture design are:· Separate the user plane functions from the control plane functions for scalability andflexible deployments, especially towards the data plane· Modularized function desing to enable customized network functiosn to be designed forthe use cases, flexible network function sharing and end-to-end network slicing· Service-oriented procedures and direct interactions between NFs – based on the webservices protocols, enabling the easy scalability of network functions as well as the easy
extension of the control plane with new functions· Minimize dependencies between the access network and the core network – still the basestations need to be bound to an AMF for control plane operations, albeit not anymore
requiring a data path binding.
· Support a unified authentication framework – a single authentication framework is includedin the AUSF as a separate new network function instead of multiple ones, separated peraccess technology type, as in the case of 4G· Support "stateless" NFs, where the "compute" resource is decoupled from the "storage"
resource – an unstructured data repository is added to the system, enabling the network
functions to store their data in their specific format in a shared environment, thus making
them stateless and easy to remove from the system when needed.
· Support capability exposure – through the NEF, the different capabilities of the packet core
are grouped and exposed to the applications.
· Support concurrent access to local and centralized services, e. g. edge computing – withthe control-data plane separation, a very easy solution for offloading was integrated.
Through this, a dedicated data path may be terminated at local Service Hosting nodes
which are placed at the edge of the network
Some new features supported by 5G System include:

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·
·
·
·
·
·

Service based architecture – the 5G core network system is based within the control planeon micro-services protocols and services such as HTTP/2, JSON and OpenAPI and follow
a REST based communication
E2E network slicing – multiple core networks can be deployed in parallel and be
customized for the different services
Data storage architecture enabling compute and storage separation – a new data plane
was created enabling the distribution of information independent of the core network
functions.
Architectural enablers for virtualized deployment – the network functions were highly
reduced in complexity to easy fit to single servers. Additional load balancing mechanisms
were added as to enable a very easy deployment and scaling.
Common N1/N2 for 3GPP and non-3GPP access – a new level of convergence wasreached for the non-3GPP accesses which will use the same control plane interfaces forauthentication and authorization as well as for mobility management
Application influence on traffic routing – routing information can be send by the applications
to the SMF, through the PCF to enable the routing of the data traffic towards the appropriate
Service Hosting Nodes.

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4.Micro operator scenario in dense environments providing eMBB
5G is expected to open new roles in the future mobile business ecosystem through theintroduction of local 5G operators such as the recent micro operator concept [Matinmikko et
al. 2017], [Matinmikko et al. 2018], [Ishizu et al], [Filin et al]. The concept of micro operators
aims at boosting local service delivery in 5G through locally deployed small cell networks in
specific locations for tailored service delivery. The three basic elements of the micro operator
concept include 1) planning and building of local small cell infrastructure; 2) operation andmaintenance of the network infrastructure; and 3) provisioning of tailored services within thespecific location (Matinmikko et al. 2017). The concept aims to respond to the trends of change
in the 5G deployments where location specific vertical services, indoor networks and sharing
of infrastructure become increasingly important. Micro operators aim at complementing the
traditional mobile network operators' (MNO) offerings in these locations. Regarding its
customers, the micro operator can operate a closed network to serve its own human or
machine type of customers that are not served by MNOs such as in a factory setting.
Alternatively, the micro operator can act as a neutral host for other MNOs by serving theircustomers in specific high-demand locations. A hybrid is also possible where the micro
operator serves both MNOs’ customers and its own customers.
Micro operators are built on top of the technical features of dense indoor small cell networks,
operation in higher carrier frequencies (such as >3Ghz or even mmWave for increasing thecapacity as there is no need for a large coverage), and the opening of network architecture to
support multi-tenancy and network slicing for serving multiple serviced providers customers[Matinmikko-Blue et al. 2017]. The deployment of local 5G networks by micro operators
requires local spectrum availability which can be achieved through e.g. locally issued spectrum
access rights [Matinmikko et al. 2018]. This development would allow the establishment of alarge number of local small cell radio access network deployments by different stakeholders
such as facility owners to meet the versatile needs of vertical sectors in specific places withquality guarantees. This requires development of techniques for interference coordination
between micro operators as well as potential incumbent spectrum users by combining theideas from both individual and general authorization regimes to allow dynamic adaptation tochanging interference conditions and different levels of interference protection.
eMBB is one of the three major usage scenarios for 5G defined by the ITU-R [ITU-R 2015].
eMBB presents new application areas and requirements in addition to existing Mobile
Broadband for improved performance and an increasingly seamless user experience. The
eMBB usage scenario covers both wide-area coverage and hotspot cases, which havedifferent requirements and deployment models. The hotspot case typically includes high user
densities and calls for very high traffic capacity and user data rates, while the requirement formobility is low. For the wide area coverage case, seamless coverage and medium to highmobility are desired, with much improved user data rate compared to existing data rates but
not as high as in the hotspot case [ITU-R 2015]. The minimum technical performancerequirements for the eMBB usage scenario defined by the ITU-R in [ITU-R 2017] areconsiderably higher than for previous generations of mobile communications networks.
Considering the KPIs for specifically the eMBB in indoor hotspot case, the minimum
requirements for peak data rate are 20 Gb/s in downlink and 10 Gb/s in uplink, peak spectral
efficiency 30 bit/s/Hz in downlink and 15 bit/s/Hz in uplink, average spectral efficiency 9 bit/s/Hz
in downlink 9 and 6.75 bit/s/Hs in uplink, and area traffic capacity in downlink 10 Mbit/s/m2[ITU-R 2017]. Meeting these requirements calls for the development of new eMBB techniques
as well as new operator models to address the eMBB usage scenario in hotspot case.

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3GPP standardization related to micro operator scenario is ongoing within two study items in
Release 16:· FS_ATSSS: Study on Access Traffic Steering, Switch and Splitting support in the 5G
system architecture [TR 23.793]· FS_Vertical_LAN: 5GS Enhanced support of Vertical and LAN Services [TR 23.734].
FS_ATSSS study is considering scenario where micro operator is using non-3GPP RAT, forexample: WiFi.
FS_Vertical_LAN considers various deployment scenarios where micro operator is using 5G
NR RAT.
Figure 6 shows a micro operator scenario that may benefit from network sharing. Operator A
is large area network operator, operator X is local area network operator (for example, insideresidential, commercial, or industrial property). F1 is lower frequency allocation, F2 is newhigher frequency allocation used for micro cells.
Micro cells of local area operator X may have better coverage inside this specific local area
than micro cells of large area operator A. Also, micro cells of local area operator X are capableof supporting one or several sets of QoS requirements tailored for specific classes ofapplications compared to micro cells of large area operator A (for example, tailored for highdata rate or low latency applications).
There are several options to provide a connection to an application for the scenario shown in
Figure 6.
CN A

Simplified CN X

A, F1
X, F2

A, F2

UE

Figure 6 Small cell sharing scenario
One of the options is shown in Figure 7. Solid lines correspond to data, dashed lines
correspond to control information. Here, large area operator A macro cell is used for control
information. Large area operator A micro cell or local area operator X micro cell is used fordata (selection is based, for example, on coverage, required QoS requirements, etc).

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Figure 7 Option 1 to provide a connection to an application.
Another option is shown in Figure 8. Solid lines correspond to data, dashed lines correspondto control information. Here, local area operator X micro cell is used for data. Large area
operator A macro cell or local area operator X micro cell is used for control information(selection is based, for example, on required CN functionality).
CN A

Simplified CN X

A, F1
A, F2

X, F2

Selection

Figure 8 Option 2 to provide a connection to an application.
Also, network sharing technology is one of the ways to increase flexibility and efficiency ofspectrum usage. For example, some dedicated spectrum may be assigned to each of theconventional network operators while some part of the spectrum may be assigned to a shared
network.
A shared network operator may allocate shared resources to the participating operators basedon their planned and current needs and according to service level agreements. This will help
to take into account varying spectrum needs of conventional operators.

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5.New requirements to realize micro operator scenario (for eMBB)
5.1 Network Sharing (CN) requirements
This section lists requirements to 5G CN in order to realize micro-operator scenario for eMBB
in dense environments. It is largerly based on [TR 22.804] and [TR23.734]. These
requirements are trying to identify what new features are needed on top of Release 15 5G CN.
Requirements in [TR 22.804] and key issues in [TR23.734] are extended in order to better
serve the goals of the 5G-Enhance project.
Network service requirements are as follows:· The 5G system shall support micro-operator networks, as defined in the previous
section· The 5G system shall support micro-operator networks that provide coverage within a
specific geographical area.
· The 5G system shall support unique network identifiers for micro-operator networks.
· The 5G system shall support micro-operator networks as tenant-centric network slices
with traffic, QoS, and service separation between tenants, e.g., communication
services of one tenant do not interfere with communication services from anothertenant.
· The 5G system shall support multi-tenancy in a micro-operator network such that there
may be restrictions on which resources an individual tenant is allowed to access.
· The 5G system shall support capability to deploy micro-operator network in either
licensed or unlicensed bands.
·

Subject to an agreement between the operators/service providers, operator policies
and the regional or national regulatory requirements, the 5G system shall support
mobility between a micro-operator network and a public PLMN.

·

The 5G system shall be able to expose a suitable API to provide the information
regarding the geographic location of coverage area (e.g radio cell sector coverage) toan authorised 3rd party.
The 5G system shall be able to expose a suitable API to provide the information about
the allocated and free network service resources in the network to an authorised user.
The 5G system shall be able to expose a suitable API for monitoring the resource
utilisation of the network service in a micro-operator network (radio access point andthe transport network (front, backhaul) by an authorised 3rd party.
A micro-operator network shall be able to expose a suitable API to allow an authorised
3rd party to define and reconfigure the properties of offered 5G communication
services.
The 5G system shall be able expose a suitable API for an authorised 3rd party
application to negotiate communication service requirements.
The 3GPP system shall support a suitable API for an authorised 3rd party to provide
information about the required transmission QoS desired for different granularity of datatransmitted of the 3rd application.
The 5G system shall be able to expose a suitable API to provide the connectivity status
and geographic position of all UEs and their radio access points to an authorised user.

·
·
·
·
·
·
·
·

The 5G system shall support a mechanism for a UE to identify a micro-operator
network.
The 5G system shall support a mechanism to allow a UE to select a micro-operator
network that it is authorised to access.

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A UE shall be able to detect the availability of a micro-operator network before
attempting to access a cell of this network.

5.2 Spectrum sharing requirements
The main new feature of 5G-Enhance system model is that it supports local micro operator
deployments indicating that different stakeholders can deploy local 5G-Enhance networks. The
local micro operator may need to share the spectrum with an incumbents, or with between thepotentially a large number of other local micro operators. In the following, we present the
spectrum sharing related requirements for the 5G-Enhance system:· The 5G Enhance system shall support both different levels of spectrum access rights
ranging from exclusively licensed to unlicensed spectrum bands.
· The 5G Enhance system shall support sub 6GHz band and mm-wave spectrum bandfor sharing the spectrum among the micro-operator networks.
· The 5G Enhance system shall have the capability of supporting dynamic spectrum
demand over a period of time for micro-operator networks.
· The 5G Enhance system shall have the capability to mitigate interference fromincumbent’s to micro-operator networks (operating both indoor and outdoor).
· The 5G Enhance system shall have the capability to protect incumbents while sharing
its spectrum band with the micro-operator networks as defined by the regulators.
· The 5G Enhance system shall support flexible spectrum sharing schemes among
micro-operators and incumbents depending on the various parameters gathered by theoperators.
· The 5G Enhance system shall allow an intense reuse of the sharing spectrum in denseareas, in order to increase the spectrum utilization.

5.3 Possible technologies/directions to satisfy requirements
Based on the network service requirements listed im Section 5.1 in order to realize network
sharing it might be interested to study the following topics within this project.
Network identification for micro-operator networks:· What information elements are included in the micro-operator network identification,e.g., network operator identifier, type of the network, location information?
· What are the assumption on the uniqueness of the micro-operator network
identification?
Network discovery, selection and access control for micro-operator networks:· Subscription to micro-operator networks.
· How is micro-operator network ID provided to the UE for network discovery andselection?
· Which criteria are used by the UE for selection of micro-operator network?
· What supporting information is provided to the UE for selection of micro-operator
network?
· How to perform access control?
Access to PLMN services via micro-operator network:· How to access public PLMN services via micro-operator network?
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How to access selected micro-operator network services via public PLMN?

For an efficient spectrum sharing, smart spectrum is a key concept. In the spectrum sharing
among multiple wireless networks, such as micor operator network, macro operator network,and different type of wireless networks, the spectrum sharing requirements have to be satisfied.
In smart spectrum access, there are four key functional technologoies: measurement,
database, learning, and spectrum management and they can enhance efficiency of thespectrum sharing.
A spectrum measurement system in smart spectrum is required to be able to perform wideband, long-term, and wide area spectrum measurement. Implementation cost of the spectrum
measurement system is an issue. For this issue, low cost of sensor is desirable. The sensing
accuracy is low due to individual sensing ability and physical orientation of each sensor.
Therefore a calibration method has to be established. In the measurement based spectrum
database, it is required a large numbers of measurement data sets for improving the accuracyof the data in wide support area. Crowd sensing by using mobile terminals like smart phones
is one of the solutions for gathering the datasets.
The observed data is stored in spectrum database/data server through the internet andlearning algorithms are employed to undertand aspects and characteristics of spectrum usage
and extract useful information for efficient spectrum management and spectrum sharing.
Multidimensional (time-space-frequency) learning algorithm for spectrum usage modeling andprediction can provide several benefits in the spectrum sharing to achieve the requirements in
5G Enhance. For example, time domain measurement and learning can provie statisticalinformation of spectrum utilization and it is useful to design a proper access scheme forinterference mitigation in the spectrum sharing. In addition, this information may be useful tosatisfy the dynamic spectrum demand. In addition, multidimensional spectrum usage model
can enhance the flexible spectrum sharing schemes.
The smart spectrum management considering spectrum efficiency with satisfying the user
demands are the important issue. In this project, the smart spectrum utilization with reliability
according to the user demand and with improving the spectrum sharing efficiency among
multiple operators by using the extracted information through measurenet, database, andlearning process.
· Considering the database architecture for smart spectrum management· Design of the database based on the spectrum measurement results and spectrum
usage models· Development of spectrum resource management for efficient spectrum sharing andguaranteeing communication reliability
Development of spectrum management server for allocating and sharing the spectrum
for multi-operator scenario
We plan to develop a spectrum manager for spectral management and coexistence of micro
operators. Development of various management and coexistence mechanisms tailored toenable high-spectral efficiency and to avoid energy-wasteful interference between operators,
will be addressed.

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6. 5G Architecture and functional enhancements for micro operator
support of eMBBThis Section presents the primelary architecture of the 5G Enahnce stem that will be refinedlater in the project if needed.
6.1 Spectrum Sharing
Figure 9 illustrate an architecture of spectrum sharing based on the smart spectrum concept.
Efficiency, flexibility, and scalability of the spectrum sharing can be enhanced by the four key
technologies of the smart spectrum concept and the four key technologies are measurement,
database, learning, and spectrum management. Wireless networks A, B can be either macro
operator based wireless network or micro operator based wireless network. The learning canprovide useful information based on the measurement results to spectrum resounce manager
and the network performances can be enhanced to achieve the requirements.

Figure 9: Architecture of spectrum sharing based on the smart spectrum concept

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6.2 Network Sharing
Figure 10 illustrates new functional enhancements that would be enabled by micro operator
scenario to realize eMBB use cases.
5G RAN Sharing
5GC A

5G CN Sharing

5GC X

5GC B

5GC A

5GC X

X, F_X

5GC B

X, F_X

A, F_X

A, F_X
A, F_AA, F_A
B, F_X

B, F_X
B, F_B

Operator A Frequency

Shared Higher Frequency

B, F_B

Operator B Frequency

Operator A Frequency

Shared Higher Frequency

Operator B Frequency

Figure 10 Function enhancements for micro operator support for eMBB.
Using RAN sharing and/or CN sharing users from public PLMNs could have access to services
provided by a micro-operator network in localized geographic areas. In addition to network
sharing, spectrum sharing between public PLMNs and micro-operator network could bepossible in specific frequency bands subject to national and international radio regulations.
Figure 11 shows an example system architecture to implement micro-operator scenario using
network sharing technology.
NSSF
Nnssf

NEF
Nnef

NRF
Nnrf

PCF

AF

Npcf

Naf

Namf

UE

(R)AN
Shared network

N3

SMF

Nnef
Nausf
AUSF

PCF
Npcf
Nnrf
NRF

Nnssf
NSSF

N
4

N2

NEF

Nudm

Nsmf

AMF

N1

UDM

UPF

N6

DN

Participating operator network or shared network

Participating operator network

Figure 11 System architecture to implement micro-operator scenario using network
sharing technology.
The left side of Figure 11 shows the minimum set of functions provided by a shared network.
If only this set of functions is shared, this corresponds to RAN sharing. The right side of Figure
11 shows the minimum set of functions provided by a public PLMN. The middle part
corresponds to CN sharing. How they are split between a public PLMN and a shared microoperator network is flexible and depends on particular deployment.
How the architecture in Figure 11 could be enhanced and how it may need to be modified tosupport vertical service and access traffic steering, switch and splitting would be studied within
this project.
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7. Summary
In this deliverable, the basis for the further development of the Advanced Spectrum andNetwork Resouce Management (ASNRM) solution addressing the needs of dense urban
areas. In particular a micro-opertor scenario based on spectrum and network sharing
technologies is considered within 5G Enhance project.
Motivation for sharing could be briefly summarized as follows:· Reduction of deployment and maintenance cost for public operators by using RAN and CN
resources of shared networks· Creating new business models and opportunities for competition and service level
improvements by enabling micro-operator deployment scenarios· Improving spectrum utilization efficiency by using various spectrum sharing technologies.
In this project the current 4G and Release 15 5G systems are taken as the baseline. On top ofthem new service and functional requirements are formulated to realize spectrum sharing andmicro-operator scenario.
Based on the requirements several directions and technologies are selected that will be focus
for R&D within 5G Enhance project leading to other deliverables and demonstrations.
Also, draft system architecture is proposed that will be futher improved within the duration of
the project.

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References[TS 23.251][TR 22.951][TR 22.861][TR 22.862][TR 22.863][TS 23.501][TS 23.502][TS 23.503][TR 23.793][TR 23.734][TR 22.804][Tehranial. 2016]

et[ITU-R 2017][ITU-R 2017][Matinmikko
et al. 2017a][MatinmikkoBlue et al.
2017][Matinmikko
et al. 2018][Ishizu et al][Filin et al]

3GPP, “Network sharing; Architecture and functional description”, 2018-09-17
3gPP, “Service aspects and requirements for network sharing”, 15.0.0, 2018-07-04
3GPP, “FS_SMARTER - massive Internet of Things”, 14.1.0, 2016-09-30
3GPP, “Feasibility study on new services and markets technology enablers for criticalcommunications; Stage 1”, 14.1.0, 2016-10-04
3GPP, “Feasibility study on new services and markets technology enablers for enhanced
mobile broadband; Stage 1”, 14.1.0, 2016-09-30
3GPP, “System Architecture for the 5G System”, 15.3.0, 2018-09-17
3GPP, “Procedures for the 5G System”, 15.3.0 2018-09-17
3GPP, “Policy and Charging Control Framework for the 5G System; Stage 2”, 15.3.0
3GPP, Study on access traffic steering, switch and splitting support in the 5G systemarchitecture, 1.0.0, 2018-09-08
3GPP, “Study on enhancement of 5GS for Vertical and LAN Services”, 0.2.0, 2018-09-10
3GPP, “Study on Communication for Automation in Vertical domains (CAV)”, 16.0.0, 2018-0705
R. H. Tehrani, S. Vahid, D. Triantafyllopoulou, H. Lee and K. Moessner, "Licensed Spectrum
Sharing Schemes for Mobile Operators: A Survey and Outlook," in IEEE Communications
Surveys & Tutorials, vol. 18, no. 4, pp. 2591-2623, Fourthquarter 2016.
ITU-R, "Minimum requirements related to technical performance for IMT-2020 radio
interface(s)“. Report ITU-R M.2410. 2017.
ITU-R, "Minimum requirements related to technical performance for IMT-2020 radio
interface(s)“. Report ITU-R M.2410. 2017.
M. Matinmikko, M. Latva-aho, P. Ahokangas, S. Yrjölä & T. Koivumäki. Micro operators to boost
local service delivery in 5G. Wireless Personal Communications, vol. 95, no. 1, pp. 69–82, May
2017.
M. Matinmikko-Blue and M. Latva-aho. Micro operators accelerating 5G deployment. 12th IEEE
International Conference on Industrial and Information Systems (IEEE ICIIS 2017), Peradeniya,
Sri Lanka, 15-16 December 2017, pp. 1-5.
M. Matinmikko, M. Latva-aho, P. Ahokangas & V. Seppänen. On regulations for 5G: Microlicensing for locally operated networks. Telecommunications Policy,
Vol. 42, No. 8, Sept. 2018, pp. 622-635.
K. Ishizu, H. Murakami, K. Ibuka, F. Kojima, “Coordinated Management of Multiple Wireless
Networks and Spectrum Sharing toward The Fifth Generation Mobile Communication
Systems,” IEICE Tech. Rep., vol. 117, no. 56, SR2017-7, pp. 39-46, May 2017.
S. Filin, H. Murakami, K. Ishizu, F. Kojima, “Network sharing and spectrum sharing scenarios
for future 5G networks,” IEICE Tech. Rep., vol. 117, no. 133, SR2017-25, pp. 9-13, July 2017.

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