eNodeB Operation & Maintenance Basics

Prepared by: Samsung

Approved by:RJIL

Detailed Schedule

Day Course Topics

Day 1 LTE Concepts O&M

LTE Network Architecture

LTE Air Interface

eNodeB Call Processing

Day 2 Introduction to Samsung eNodeB

Samsung eNodeB Overview

LSM-R Overview

LSM-R Operations Basics

Day 3 eNodeB Growth

eNodeB growth for PnP

LSM-R Operations Hands on

LSM-R Growth Hands on

Day 4 Troubleshooting

Hands On

eNodeB Growth Troubleshooting

Post Test and Feedback

Course Name: eNodeB O&M Basics

Course Objective

This module will enable participantsto understand entry-level overviewof Samsung eNodeB and operations

Who Should Attend

O&M Engineers, RAN engineerswho do not have experience onSamsung platform

Pre-Requisite Basic understanding LTE

Morning Session (11am to 1:30pm)

Lun

ch b

reak

Afternoon Session (2:30pm to 6pm)

Day 1

• Introduction to LTE

• LTE Network Architecture

• LTE Air Interface Basics

• Samsung eNodeB Call Processing

Good to Know

Keep your mobile phone in the silent mode during the session

Facebook/Twitter etc. Not Allowed. You can be online on your office mail

Need to sign attendance sheet at the start and end of each day

At the end of each training pre and post test will be conducted

Stick to break timings

Your valuable feedback will be taken at the end to enhance training experience

Certificate will be issued to successful participant

For logistics support contact the coordinator

Agenda: Day 1

LTE Network Architecture

Cellular Architecture (2G and 3G)

LTE RAN & Core Philosophies

LTE Air Interface

Air Interface of EUTRAN

OFDMA in downlink and SC-FDMA in Uplink

FDD and TDD duplex methods

Scalable bandwidth 1.4MHz to 20MHz

MIMO (Multiple Input Multiple Output) Introduction

Samsung eNodeB Overview

Samsung eNodeB Specs

Samsung eNodeB Key Features

Samsung eNodeB Hardware

Commissioning of Samsung eNodeB

LTE Network Architecture

LTE Architecture Philosophy

Single node e-UTRAN

Packet based while supporting real time conversational traffic

Minimize number of interfaces

Minimizes single points of failure

Supports end-to-end QOS

Supports QOS differentiation between control, user and O&M traffic

Flat architecture

Supports interworking with a variety of wireless networks

eUTRAN

EPC

IP Cloud

LTE Network

IP Cloud

PCRF

HSS

OFCS

OCS

LSM-R

SON

MCE

GGSN

SGSN

MME SGW

PGW

MBMS GW

BMSC

X2

S1-MME S1-U

S11

S5

SGi

S6a

Gx

Gy

Gz

S3

S4

Gi

Gn

Gx

M1

M2

M3Sm

SGmb

SGImb

LSM-C

WCDMA LTE NMS

eNodeB

RRM functions

Radio Bearer Control

Radio Admission Control

Connection Mobility Control

Dynamic resource allocation UL& DL

IP header compression andencryption of user data

Selection of MME at the time ofUE attachment

Measurements for mobility

Scheduling and transmission ofpaging and broadcast

eNodeB

eNodeB

X2

Uu

E-UTRAN

MMES1-AP signalling

Signaling coordination for SAE Bearer Setup/Release

NAS signaling and security

Authentication, integrity Protection

Inter CN node signaling for mobility between 3GPP access networks (S3)

Location registration and Paging for Idle mode UE

Paging, TA list management, Tracking Area Updates

NE selection

PDN GW, Serving GW selection

MME selection for handovers with MME change

SGSN selection for handovers to 2G or 3G access network

Roaming for interworking HSS (S6a interface)

Interworking for Non-3GPP network

HRPD interworking (S101 interface) :

- Signaling for HRPD network and Optimized Handover

Serving Gateway

Interfacing E-UTRAN for bearer

Local Mobility anchor point for inter- eNodeB Handover

Mobility anchoring for inter-3GPP mobility (terminating S4 and relaying thetraffic between 2G/3G system and PDN GW) Packet routing & forwarding

Paging to ECM-Idle mode UE for incoming call

Accounting for inter-operator changing

UL/DL transport level packet marking e.g. setting the DiffServ Code Point,based on the QCI of the associated EPS bearer

Lawful Interception

PDN GatewayInterfacing external PDN

Mobility anchor point between Non-3GPP and 3GPP

Packet routing & forwarding

UE IP address allocation

Per-user based packet filtering (i.e. deep packet inspection)

Packet screening (firewall functionality)

PCEF (Policy and Charging Enforcement Function) function

UL/DL bearer binding and UL bearer binding verification

Service level charging, gate control, rate enforcement

PCRF interworking and Policy / Charging control

DL rate enforcement based on APN-AMBR, MBR

UL/DL transport level packet marking e.g. setting the DiffServ Code Point, based on theQCI of the associated EPS bearer

Accounting for inter-operator charging

HSS & PCRF

HSS (Home Subscriber Server)

User id, numbering, addressing information storage

User security information generation

• mutual authentication and encryption for between UE and network

User location information storage

User profile information storage

PCRF (Policy and charging rule function)

Sending QoS and charging rule to P-GW(PCEF) for SDF (Service Data Flow) and IP-

CAN Session

• P-GW (PCEF) performed QoS and Charging functions according to PCC rule

eMBMS Elements

MCE (MBMS Coordination Entity)

The MBMS Coordination Entity (MCE) is a logical node that is responsible forallocating time and frequency resources. The MCE acts as an MBMS schedulerwhich allocates radio resources, performs session admission control andmanages MBMS services.

MBMS GW

The MBMS GW is a logical entity whose main function is to deliver MBMSpackets to each eNodeB transmitting the service. It uses IP multicast to deliverthe downlink packets.

Broadcast Multicast Service Center (BM-SC)

The BM-SC is responsible for authentication, content authorization, billing andconfiguration of the data flow through the core network. It acts as a proxycontent server.

Samsung Smart Scheduler

Uses general purpose hardware platform – IBM Blade Center HT Chassis and HS23 Blade server

Implemented in software by General Purpose Processor (GPP)

Minimizes inter-cell interference

Improves cell-edge throughput

Centralized management for multiple eNB’s

10 blades per server support total 2880 cells

X2

SC1

SC1

LSM

E-UTRAN

InterfacesX2 Interface

Between eNodeB.

It supports the exchange of signaling info between eNBs most commonly for Handover

Also supports forwarding of user PDUs

S1-MME Interface

S1-MME for exchange of signaling messages between the eNB and the MME

S1-U Interface

S1-U for the transport of user datagram's between the eNB and the Serving Gateway (S-GW)

Supports Inter eNodeB path switching during handover

S3 Interface

Interface between SGSN and MME

Enables user and bearer information exchange for inter 3GPP access

Manages Network mobility in idle and/or active

InterfacesS4 Interface

Interface between SGSN and Serving SAE Gateway

It provides control and mobility support between GPRS Core & 3GPP

Anchor function of Serving GW

Alternate plane tunnel in case of no Direct Tunnel

S5 Interface

Interface between S-GW and P-GW

User plane tunneling and tunnel management

It is used for Serving GW relocation due to UE mobility or connections to a non-collocatedPDN GW

S6a Interface

Interface between HSS and MME

Enables transfer of subscription and authentication data

InterfaceS8 Interface Interface between Serving GW in the VPLMN and the PDN GW in the HPLMN.

Inter-PLMN reference point providing user and control plane between the Serving GW in theVPLMN and the PDN GW in the HPLMN

S10 Interface Reference point between MMEs for MME relocation and MME to MME information transfer

S11 Interface Reference point between MME and Serving GW

Gx Interface It provides transfer of (QoS) policy and charging rules from PCRF to Policy and Charging

Enforcement Function (PCEF) in the PDN GW

SGi Interface It is the reference point between the PDN GW and the packet data network. Packet data

network may be an operator external public or private packet data network or an intraoperator packet data network, e.g. for provision of IMS services. This reference pointcorresponds to Gi for 3GPP accesses.

LTE Protocol Stack – User Plane

User Plane - consists of PDCP, RLC, MAC, and PHY layers, responsiblefor transmitting user data (e.g. IP packets) received from the higherlayer. All protocols in the user plane are terminated in the eNB.

Interface between UE and eNB

Application

IP

PDCP

RLC

MAC

L1

IP

GTP-U

UDP-IP

L2

L1

UE

LTE-Uu S1-U S5/S8

eNB

PDCP GTP-U

RLC UDP-IP

L2 L2

L1 L1

GTP-U GTP-U

UDP-IP UDP-IP

L2 L2

L1 L1

Relay Relay

S-GW

LTE Protocol Stack – Control Plane

Control Plane - consists of NAS, RRC, PDCP, RLC, MAC, and PHY layers. Locatedabove the wireless protocol, the NAS layer is responsible for UE authenticationbetween the UE and MME, security control, and paging/mobility managementof UEs in LTE idle mode, all protocols except the NAS signal are terminated inthe eNB.

NAS

RRC

PDCP

RLC

MAC

L1

NAS

S1 - AP

SCTP

IP

L2

L1

UE

LTE-Uu S1-MME

RRC S1 - AP

PDCP SCTP

RLC IP

MAC L2

L1 L1

Relay

Protocol Stack

Interface between eNB and EPC : A physical connection between the eNB and EPCis established through the FE and GE, and the interface standards should satisfy theinterface between the LTE S1-U and S1-MME. The user plane uses the GTP-User(GTP-U) above the IP, and the control plane uses the SCTP above the IP.

GTP-U

UDP

IP

MAC

PHY

GTP-U

UDP

IP

MAC

PHY

User Plane PDUs

User Plane PDUs

SCTP

IP

MAC

PHY

SCTP

IP

MAC

PHY

S1-AP S1-AP

eNB S-GWS1-U

eNB MMES1-MME

Interface between eNodeB

Interface between eNodeB

A physical connection between the eNBs is established through the FE and GE, andthe interface standards should satisfy the LTE X2 interface. The user plane protocol stacks between the eNBs are shown below

GTP-U

UDP

IP

L2

L1

GTP-U

UDP

IP

L2

L1

User Plane PDU

User Plane PDU

SCTP

IP

L2

L1

SCTP

IP

L2

L1

X2-AP X2-AP

eNBX2-U X2-C

eNB eNB eNB

Interface between eNB and LSM

A physical connection between the eNB and LSM is established through the FEand GE, and the interface standards should satisfy the FTP/SNMP interface.The interface protocol stacks between the eNB and LSM are shown below

TCP UDP

IP

L2

FTP SNMP

L!

TCP UDP

IP

L2

FTP SNMP

L1

eNB LSMFTP/SNMP

Transport Network Hierarchy

CSR

CSR

CSR CSR

AG1

AG1 AG1

AG1

AG2AG2

AG3 AG3

eNBeNB

eNB

eNB

A pair of AG3 routers per site

Up to 16 pairs of AG2 routers

Dual-homing with AG3 routers

Up to 10 AG1 rings

Up to 4 AG1 routers in a ring

Dual-homed ring with AG2 routers

Up to 4 CSR rings

Up to 5 (fiber) or 4 (MW or fiber + MV)

eNBs per ring

Dual-homed with AG1 routersCSR and eNB

AG2 node

R4G Network Deployment Quantification

Mumbai

Zones ( 2)

NP GW

OCS

NP GWMNP GWIMS Apps

eSMLC / GMLC

LIM - BE

IPSM / SMSC NW IVR

Content MgmtSelf CareOCS OSS

MNP GW

OCS

IMS Apps IPSM / SMSCNW IVR

eSMLC / GMLC

Content Mgmt

Regions (4)

EPC ( 18)

Delhi

IMS Core

MGCF

TAS/OTM

DNS/ENUM

NPDB

PCRF

DRA

HSS

AAA / PS

Ld Bal.

West (Mumbai)

NIMS

eMBMS GW

BMSC MCE DPIL4/L7

NIMS

MRFSBC WAGLIM FE IBRL2 SW

MMESAE GW

LSM R/C

Circles ( 22)

MGW RAN Scheduler eNodeB

South (Chennai)

IMS Core

MGCF

TAS/OTM

DNS/ENUM

NPDB

PCRF

DRA

HSS

AAA / PS

Ld Bal.

North (Delhi)

IMS Core

MGCF

TAS/OTM

DNS/ENUM

NPDB

PCRF

DRA

HSS

AAA / PS

Ld Bal.

East (Kolkata)

IMS Core

MGCF

TAS/OTM

DNS/ENUM

NPDB

PCRF

DRA

HSS

AAA / PS

Ld Bal.

Zonal & Regional Level Nodes will work in Active- Active (Load sharing) mode

EPC++EPC IMS Wi-Fi Supporting OSS/BSSLegend RAN

Summary

LTE architecture is completely packet-based

Single node RAN

Flat architecture EPC

eNodeB performs all the RRM functions

MME performs all control plane core functions

S-GW is the local mobility anchor. Facilitates inter-3GPP handovers

P-GW assigns IP address and applies policy and QoS

Quiz

Radio resources are allocated by

• eNodeB

• S-GW

_____ establishes a connection between the UE and EPC

• S-GW

• P-GW

• MME

During handover DL data is buffered at

• S-GW

• MME

• P-GW

LTE RAN Technologies

LTE Key Parameters

Frequency Range UMTS FDD bands and UMTS TDD bands

Channel Bandwidth, 1Resource Block (RB) = 180KHz

1.4MHz 3MHz 5MHz 10MHz 15MHz 20MHz

6 RBs 15RBs 25RBs 50RBs 75RBs 100RBs

Modulation scheme

Downlink: QPSK, 16QAM, 64QAMUplink: QPSK, 16QAM, 64QAM (optional for handset)

Multiple AccessDownlink: OFDMAUplink: SC-FDMA

MIMOTransmit diversity, Cyclic delay diversity (Max. 4 antenna at Base station & handset)Spatial multiplexing, Multiuser MIMO

Peak Data rateDownlink: 150Mbps (UE category 4, 2x2 MIMO, 20MHz)

300Mbps (UE category 5, 4x4 MIMO, 20MHz)Uplink: 75Mbps (20MHz)

Cyclic PrefixCyclic Prefix (CP) is transmitted in the guard time interval

OFDMA symbol duration including CP is approximate 71.4 µs.

Long duration when compared with 3.69µs for GSM and 0.26µs for WCDMA

Symbol length without CP: 66.67µs (1/15kHz)

12

34

time

TSYM

BOL

Time Domain

time

time

Tg

1

2

3

time

4

Cyclic Prefix DetailsCopies the last part of a symbol shape for a duration of guard-time and attach it in frontof the symbol

CP Types

Normal CP: for small cells or with short multipath delay spread

Extended CP: designed for use with large cells or those with long delay profiles

t

Total symbol time T(s)

Guard Time T(g)

CP T(g)

Useful symbol time T(b)

Note: CP represents an overhead resulting in symbol rate reduction.

Last part of the symbol is used as Cyclic Prefix

(CP)

CP ratio = T(g)/T(b)

OFDMA

Flexible resource allocation

Robustness against multipath

The peak (centre frequency) of one subcarrier …

…intercepts the ‘nulls’ of the neighbouring subcarriers

15 kHz in LTE: fixed

Total Bandwidth

OFDM Transmission Basics

Data is sent in parallel across the set of subcarriers

The throughput is the sum of the data rates of subcarriers

Power

Frequency

Bandwidth

01 10 11 01 01

10

11

01

OFDMA Symbol

S/P

Serial to Parallel

LTE Time-Frequency Grid

Fast time-domain scheduling

Radio resources on a time-frequency grid

Freq

ue

ncy

•Resource Block 180 KHz x 0.5 ms•Each RB = 12 x 7 = 84 RE’s

Time

Sub-carrier 1

Sub-carrier 12

Symbol 0 Symbol 6

FFT in OFDMFast Fourier Transform (FFT) and the Inverse Fast Fourier Transform (IFFT) allows tomove between time and frequency domain representation

OFDM signals are generated using the IFFT

Fourier Transform

Inverse Fourier Transform

OFDMA Operation Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individualusers as shown below

S/P IFFT CP

Modulation mapping e.g.

QPSK symbols

Transmitter Receiver

P/SFFTCP

Remove

Modulation mapping e.g.

QPSK symbols

Total Channel Bandwidth

Transmitted Sub-Carriers

User 1

User 2

User 3

OFDMA PAPR RatioThe transmitted power is the sum ofthe powers of all the subcarriers.

The higher the peaks, the greaterthe range of power levels.

Not best suited for use with mobile(battery-powered) devices

Comparison SC-FDMA v/s OFDMA

OFDMA transmits data in parallel across multiple subcarriers

SC-FDMA transmits data in series employing multiple subcarriers

Can reduce the PAPR between 6…9dB compared to OFDMA

OFDMA SC-FDMA

01 10 11 01 01

10

11

01

OFDMA Symbol

S/P

01 10 11 01

SC-FDMA Symbol

FFT

01 10 11 01

SC-FDMA & OFDMA Time-Frequency View

LTE FDD and TDD Modes

Uplink Downlink

Bandwidth

up to 20MHz

Duplex Frequency

f

t Bandwidth

up to 20MHz

Gu

ard

Peri

od

f

t

Uplink

Downlink

Bandwidth

up to 20MHz

LTE Radio Frames, Slots and Sub frames FDD mode

The basic EUTRAN Radio Frame is 10 ms long.

The EUTRAN Radio Frame is divided into 20 slots, each one 0.5 ms long.

Always two slots together form a subframe. The subframe (1 ms) is thesmallest time unit the scheduler assigns to physical channels.

In case of TDD there is a time offset between uplink and downlinktransmission.

Frame structure type 1

#0 #1 #2 #3 #18 #19

1 radio frame (Tf = 307200×Ts = 10 ms)

1 slot (Tslot = 15360×Ts = 0.5 ms)

1 subframe (1 ms)

LTE Frame Details

Frame (10ms)

10 Sub-frames (1ms) per frame

2 slots (0.5ms) per sub-frame

7 OFDM symbols per slot

Frame (10msec)

……………

Sub frame 0

0.5 msec 0.5 msec

Slot 0 Slot 19Slot 1 Slot 18

Sub frame 9

. …….

OFDM SYMBOL 0 OFDM SYMBOL 13

CP0=5.2uSec - CP1 TO CP13 =4.7uSecSingle Sub Frame (1 ms)

…..…..

LTE Radio Frames, Slots and Sub frames TDD mode

Frame structure type 2

0 1 2 3 4 5 6 7 8 9

TDD Frame 10ms , 10 subframes 1ms each

Special Subframes 1 & 6

0 2 3 4 5 7 8 9

DwPTS

Gp

UpPTS DwPTS

Gp

UpPTS

LTE Frame Structure Type 2: Applicable to TDD

Every subframe will have two slots of 0.5ms as in FDD Frame

LTE Radio Frames, Slots and Sub frames TDD mode

LTE TDD Special Subframe Configuration (UL & DL capacity)

Asymmetric UL/DL Capacity Allocation

Single sub-frame for UL and 8times sub-frame for DL per 10ms frame

UE is informed about UL/DL configuration via SIB-1, which is broadcast via BroadcastChannel (BCH)

UL/DL Configuration

Downlink-To-UplinkSwitch-Point Periodicity

Subframe Number0 1 2 3 4 5 6 7 8 9

0 5 ms D S U U U D S U U U

1 5 ms D S U U D D S U U D2 5 ms D S U D D D S U D D

3 10 ms D S U U U D D D D D4 10 ms D S U U D D D D D D

5 10 ms D S U D D D D D D D

6 5 ms D S U U U D S U U D

Summary

OFDMA allows flexible resource allocation

OFDMA maps one modulation symbol on a subcarrier and transmits multiplesubcarriers in parallel

A Cyclic Prefix is added to an OFDMA symbol for protection against ISI

OFDMA is implemented using FFT

Due to high PAPR issues, LTE uplink uses SC-FDMA

SC-FDMA transmits in series, mapping each modulation symbol on all theallocated subcarriers

Quiz

Give two advantages of OFDMA

• Flexible bandwidth allocation

• Robustness against multipath

SC-FDMA sends ____ modulation (e.g. QPSK) symbol(s) on ____ subcarrier(s)

• 1, N

• N, N

• 1/N, N

FFT is a must in implementing OFDMA

• True

• False