5G Network Arcitucure Deployment From 4G To LTE PDF

 

5G network: Architecture & 3GPP standards progress

Complete standard standard of 5G by 2020 in 2 phases. Rel-15 Rel15 by Q2’2018, RelRel-16 by Q1’2020.

 

5G Target, Target, used cases and design principle pri nciple 5G wireless access is being developed with three broad use case Extreme Throughput. Enhanced mobile broadband (eMBB) Enhanced spectral efficiency efficiency.. Extended coverage.

5G Performance Targets High data rates 10~20Gbps Low latency < 1 ms 1000 timesofthe capacitydevices (Capacity/km2) (Capacity/km2) 100 times connected 90% reduction in network energy usage

HD video, VR services, Wireless broadband

Massive machine-type communications (mMTC)

High connection density. density. Energy efficiency. Low complexity. Extended coverage.

Remote Sensors, Utility metering, Wearables, Object tracking

Ultra-reliable low-latency communications (URLLC)

Low latency. Ultra Reliability. Location precision.

Autonomous car, Industrial Indus trial automation automation,, Robotics

Flexibility  Flexible design is the key for addressing wide range of carrier frequencies (sub 1 GHz to 10 100 0 GHz), different deployment types (macro, micro, pico cells), and diverse use cases with extreme and sometimes contradictory requirements. Forward com patibility  5G Radio will continue to evolve beyond 2020, with a sequence of releases including additional features features and functionalities. Since 5 5G G radio must support a wide range of use cases (many of which are not yet defined) forward compatibili compatibility ty is of utmost importance. importan ce.

Ultra- lean desi Ultradesign gn Cellular networks transmit certain signals signal s at rregular egular intervals even when there is no data to transmit to user. Ultra-design refers to minimizing these “always on” transmissions. Network should transmit signals only when necessary which improves energy efficiency, reducing OPEX.

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5G Components Millimeter Wave The number of network-conne network-connected cted wireless devices will reach 100 times or more. One of the most crucial challenges is the scarcity of frequency frequency.. So providers are experimenting with mm Waves. There is one drawback to mm Waves — they can’t easily travel through buildings/obstacles and can be absorbed by foliage/rain. foliage/rain. That’s why 5G networks will likely augment traditional cellular towers with small cells. Small Cells Small cells are portable miniature base stations that require minimal power and can be placed every 250 meters or so. To prevent signals from being dropped, carriers could could install thousan thousands ds of these station stationss in a city to form a dense network that acts like a relay team, receiving signals from other base stations and sending data to users at any location. Massive MIMO Today’s LTE’s base stations have have a dozen ports for ant antennas: ennas: 8 for Tx and 4 for Rx. But 5G BS can support about a hundred ports, means many antennas can fit on a single array. So a BS could send and receive signals from many users at once, increasing the capacity by a factor of 22 or greater. However, installing so many antennas to causes more interference. That’s why 5G stations must incorporate beamforming. beamforming . Beamforming From massive MIMO BS, Beam forming help to reduce interference while transmitti transmitting ng from many antennas at once, signal-proc signal-processing essing algorithms plot the best Tx route through air to each user user.. So they can send individual packe packets ts in many different dir directions, ections, bouncing them off buildings/objects in a precisely coordinated pattern. By choreographing the packets’ movements and arrival time, beamforming allows many users and antennas on a massive MIMO array to exchange much more information at once. For millimeter waves: As signals are easily blocked by objects and tend to weaken over long distances. Beamforming can help by focusing a signal in a concentrated beamchances that points only inintact the direction of a interference user, rather rather than broadcastin broadcasting strengthen the signal’s of arriving and reduce for everyone elseg. in many directions at once. This approach can

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5G Components Flexible/Full duplex FDD will remain the main duplex scheme for lower frequency bands. TDD for higher frequency frequency bands (>10GHz) (>10GHz) –  – targeti targeting ng very dense deployments, as dynamic traffic varia variations tions expected, the ability to dynamically assign Tx resource resourcess (time slots) to differ different ent Tx directions- allow more effici efficient ent utiliza utilization tion of the availab available le spectrum. Full Duplex: Tx and Rx at the same time and on the same frequency frequency,, double the system capacity and reduce the system delay delay.. Access/Backhaul Integration Using common Spectrum pool, integra integrate te wireless- access link and wireless backhaul, use same basic technology for efficient spectrum utiliza utilization. tion. Direct Device to Device communication The use of mobile devices as relays to extend network coverage. Multi-Antenna Transmission 5G radio will employ hundreds of antenna elements to increase antenna aperture beyond what may be possible with current cellular technology. Tx and Rx will use beamforming to track each other to improve energy transf transfer, er, reduce interference, extent coverage and provide higher data rates at lower frequency in specific sparse deployments.

User/Control Separation Decouple user data and control functionality to allow separate scaling of user-plane and system control functionality. User data may be delivered by a dense layer of access nodes, while system information is provided via an overlaid macro layer on which a device initially accesses network. Also extend the separation of user data and system control functionality over multiple frequency bands and RATs. e.g, system control functionality for a dense layer based on new high-frequency radio access could be provided by means of an overlaid LTE layer.

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5G Components

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Network Architecture from LTE to 5G     k    r    o    w    t    e    N    E    T    L

HSS MME UE

CCNF

AUSF

NRF

UDM

Internet/DN

P-GW

S-GW

EUTRAN

UDR

NEF

SDSF

UDSF

Flexible Intercon Interconnect nect

    k    r    o    w    t    e    N    G    5

AMF N1

UE

N2

NR

SMF

PCF

N5

N4 N3

UPF

N6

DN

AF

Two options of 5G network architecture representation 1) service based 2) reference point based  5G Radio network is called New Radio (NR), Core functionality is described in following slides

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What is new about 5G New Radio Radio User plane protocol Stack Protocol Prot ocol

Brief reflec reflection tion on the anatomy anatomy of a 4G radio radio

Changes Changes in 5G May be New layer: Service Da Data ta Adaptation Protocol (SDA (SDAP). P). To support complex QoS functionality.

SDAP

PDCP

Process IP packets and provides services like compression, ciphering and integrity protection.

Duplication feature added to increase reliability. Same PDCP Data Units to be sent over different carriers (CA scenario) reducing the retransmissions.

RLC

Segmentation/concatenation Segmentation/c oncatenation and error controls [Automatic Repeat Request (ARQ)].

Disable concatenation to reduce processing time .

MAC

Scheduling, Multiplexing, Hybrid ARQ process and Manage transport blocks transferred with PHY layer layer..

New enhancements are being introduced to the HARQ procedure to speed up retransmissions

PHY

Channel coding: Turbo codes. Modulation (QPSK and up to 256QAM), MIMO. Multiple access procedures (SC-FDMA, OFDMA). LTE defines only one sub carrier spacing of 15KHz. In LTE, a slot is defined as seven OFDM symbols.

Main Spectrum ranging from 1G 1GHz Hz to 100GHzbands. Channel coding: LDPC ((low low density parity check) for user plane; Polar coding for control control plane. QPSK to 256 QAM+ may be up to 1024 QAM + л/2-BPSK л/2 -BPSK in UL. Massive MIMO with array of Antenna. Multiple access: will be OFDMA w with ith DFT-S-OFD DFT-S-OFDM M in uplink Flexible sub carrier spacing: 2n of 15KHz, reduce symbol duration thus reduce latency. 5G NR introduces a new “mini“mini-slot” occupy two symbols to enable URLCC.

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Core Network from LTE to 5G Core functions in 5G

Authentication Se Server Function (AUSF) Unified Data Management (UDM)

Unified Data Repository (UDR)

In LTE

AUC/HSS HSS

Single SDB/UCDB

Acces ccesss an and d Mob obil ilit ity y Mana Manage gem ment ent Fun unct ctio ion n (AMF AMF)

MME MME

Policy Control function (PCF)

PCRF

Functionalities

AUSF stores data for authentication of of UE

Store subscribers data and profiles. Similar to an HSS in 4G but used for both fixed and mobile access in NG core All the user data is stored in a single UDR allowing access from core and service network entities UE-based authentication, authorization, registration, reachability, mobility management and connection management. Policy control of the user based on services/access.

Session Management Function (SMF)

MME/ S-GW/P-GW

Session establishment and management and allocates IP addresses to UEs. It also selects and controls the UPF for data transfer. If a UE has multiple sessions, different SMFs may be allocated to each session to manage them individually and possibly provide different functionalities per session

User plane Function (UPF)

S-GW/P-GW

Packet routing and forwarding functions, currently performed by the SGW and Packet PGW in 4G

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Core Network from LTE to 5G cont..) Data netwCoo rkre (DfNu)nctions in 5G

InDLNTE

Common Control Network Function (CCNF) is used for Network slicing, which is common to all or several slices. It includes the Access and mobility Management Function (AMF) as well as the Network Slice Selection Function (NSSF), which is in charge of selecting core network slice instances.

Common Control Network Function (CCNF)

Structured Data Storage network function (SDSF)

ncptairotynsaelrivtiiceess operator services, Internet access orF3urd

NA

Allows the NEF to store structured data in i n the SDSF intended for network external and network internal exposure by the NEF.

Unstructured Data Storage network function (UDSF)

Allows any NF to store and retrieve its data into/from a UDSF (e.g. LI data)

Network Exposure Function (NEF)

Expose and publish network data.

NF Repository Function (NRF)

Provides registration and discovery functionality so that Network functions (NFs) can discover each other and communicate via API.

Application Function (AF)

Application/ Service

e.g OTT/Service/IMS OTT/Service/IMS

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5G Architecture Options EPC

5G Core Core

EPC

5G Co Core re

LTE

New Radio

LTE

New Radio

UE

EPC

5G Co Core re

LTE

New Radio

UE

1. Standalone LTE, LTE, EPC connected 2. Standalone LTE Rel-15, Rel-15 , 5GC connected

UE

3. Standalone NR, 5GC connected 4. Standalone 5G NR, EPC connected

5. Non Standalone, LTE assisted, EPC connected

EPC

5G Core Core

EPC

5G Co Core re

EPC

5G Co Core re

LTE

New Radio

LTE

New Radio

LT LTE E

New Radio

UE 6. Non Standalone, NR assisted, 5GC connected

UE 7. Non Standalone, NR assisted, EPC connected

UE 8. Non Standalone, LTE assisted, 5GC connected

Also non 3GPP access is considered to be integrated with 5G core

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Early 5G deployment with CUPS in LTE HSS

PCRF Gx

S6a     k    r    o    w    t    e    N    E    T    L

MME EPC NAS

UE

LTE RRC LTE PDCP LTE Uu

S11

Rx

S/P-GW-C Sx

S1-MME S1-U

EUTRAN+NR EUTRAN+NR

SGi

S/P-GW-U

UE anchored to Network over LTE/UPC control plane. Wide area coverage through LTE with NR as capacity boost as secondary RAT .

*CUPS (Rel-14): Control user plane separation in EPC, control plane and user plane decouple in S-GW/P-GW

Internet/DN

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Early 5G deployment with