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eNodeB Operation & Maintenance Basics
Prepared by: Samsung
Approved by:RJIL
Detailed Schedule
Day Course Topics
Day 1
LTE Basics
Introduction to LTE
LTE Network Architecture
LTE Air Interface
Samsung eNodeB System OverviewSamsung eNodeB Specs
Samsung eNodeB Hardware
Day 2 Introduction to LSM-R
LSM Basic Operations
FCAPS Basics
Call Tracing
Day 3 eNodeB Growth
eNodeB growth for PnP
System Checks
Neighbor Configurations
RET Operations
Day 4 Troubleshooting
eNodeB Environment Checks
eNodeB Connectivity Check
eNodeB Software Loading Issues
Course Name: eNodeB O&M Basics
Course ObjectiveThis module will enable participants to understand high-level overview of Samsung eNodeB LSM-R operations
Who Should AttendO&M Engineers, RAN engineersPre-Requisite Basic understanding of LTE
Morning Session (11am to 1:30pm) Lunch break
Afternoon Session (2:30pm to 6pm)
Day 1
• Introduction to LTE• LTE Network Architecture• Node Functions & Specifications
• Samsung eNodeB System Overview• Lab Visit
Good to Know
Keep your mobile phone in the silent mode during the session
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
Introduction to LTE Evolution of cellular networks Comparison of 2G, 3G and LTE LTE Targets
LTE Network Architecture Cellular Architecture (2G and 3G) LTE RAN & Core Philosophies LTE Air Interface
Samsung eNodeB Overview Samsung eNodeB Specs Samsung eNodeB Key Features Samsung eNodeB Hardware
Introduction to LTE
Target Services
Evolution of Cellular Networks
1980s 1990s 2000 2010 onwards
Generation
Late 90s 2003 2008
1G
2G & its evolution
3G & its evolution
4G & its evolution
LTE
GSM
Analog cellular
GPRSEDGE
UMTSHSPA
HSPA+LTE-A
9.6
Kbps
144
Kbps
384
Kbps
2Mbps
14
Mbps
84
Mbps
300
Mbps
1Gbps
Packet switched data
Circuit switched voice support
Packet core
Only changes to RAN
Changes to RAN & Core network
Deployed in the
same channel
Deployed in the
same channel
Deployed in the
same channel
Standards
Band
Peak data rates
Comparison: 2G, 3G and LTEFeatures GSM / GPRS / EDGE WCDMA / HSPA LTE
Multiple Access FDMA + TDMA CDMA OFDMA
Carrier Bandwidth 200 KHz 5 MHz 1.4 - 20 MHz
Peak Data RateGSM 9.6 KbpsGPRS 144 KbpsEDGE 384 Kbps
WCDMA 2 MbpsHSPA 14 Mbps
HSPA+ 42 Mbps LTE 100 MbpsLTE-A 1Gbps
Transmission Time Interval (TTI) EDGE 20ms WCDMA 10 ms
HSPA 2ms 1ms
Latency (user plane) ~120 ms ~40 ms ~<20 ms
Modulation schemes GMSK, 8-PSK QPSK, 16-QAM, 64-QAM
QPSK, 16-QAM, 64-QAM
Access Network BTS + BSC NodeB + RNC eNodeB
Core Network CS – MSC, GMSCPS – SGSN, GGSN
CS – MSC, GMSCPS – SGSN, GGSN
PS – MME, S-GW, P-GW
Voice & Video Calls CS CS PS
Comparison: 2G, 3G and LTE Architectures
CoreNetwork
AccessNetwork
MSC
GGSN
SGSN
BSC / RNC
eNodeB
PSTN IP
GMSC
IP
BTS / NodeB
LTEGSM / WCDMA
• Controller node in access network
• Separate CS and PS cores• Combined user and
control planes
• Single-node access network
• Completely PS network• Separate USER and
CONTROL planes
3GPP Releases
Release Functional Freeze Date Key Features
R99 March 2000 UMTS 3.84 Mcps (WCDMA FDD &TDD)
R4 March 2001 1.28 Mcps TD-SCDMA
R5 June 2002 HSDPA
R6 March 2005 HSUPA (E-DCH)
R7 Dec 2007 HSPA+ (64QAM DL, MIMO, 16QAM UL), LTE & SAE feasibility study
R8 Dec 2008 LTE work item – OFDMA, SAE work item, new IP core, 3G femtocells, DC HSDPA
R9 Dec 2009 LTE-A feasibility study, SON, LTE femtocells, Dual Cell HSUPA
R10 March 2011 CoMP study, 4-carrier HSDPA
Source: Aglient Technologies
LTE Requirements
• 100 Mbps DL & 50 Mbps UL for 20 MHz• Spectral efficiency of 5 bps/Hz DL and 2.5
bps/Hz ULData Rates
• Control plane < 100 ms• User plane (RAN) < 5msLatencies
• LTE WCDMA 500 ms NRT, 300 ms RT• LTE GSM 500 ms NRT, 300 ms RTInterworking
TD – LTE RF Bands
LTE Band Number Allocation (MHz) Width of Band (MHz)
33 1900 - 1920 20
34 2010 - 2025 15
35 1850 - 1910 60
36 1930 - 1990 60
37 1910 - 1930 20
38 2570 - 2620 50
39 1880 - 1920 40
40 2300 - 2400 100
41 2496 - 2690 194
42 3400 - 3600 200
43 3600 - 3800 200
LTE Specifications
Specification index Description of contents
TS 36.100 seriesEquipment Requirements: Terminals, Base stations, and Repeaters
TS 36.200 seriesLayer 1 (Physical layer): Physical channels, Modulation, Multiplexing, Channel coding, etc.
TS 36.300 seriesLayers 2 and 3: Medium Access Control, Radio Link Control, and Radio Resource Control.
TS 36.400 seriesNetwork Signaling & Interfaces: Architecture, S1, X2 Interfaces, etc.
TS 36.500 series UE equipment conformance testing
URL: http://www.3gpp.org/ftp/Specs/html-info/36-series.htm
SummaryLTE is the next generation in cellular evolution
It offers high data rates (up to 100 Mbps DL) and low latencies (< 5ms user plane)
It allows flexible bandwidth deployment
It uses small 1ms Transmission Time Interval (TTI) to reduce latency
It supports interworking with existing cellular standards
LTE Network Architecture
MSC
GGSNSGSN
BSC
GSM / GPRS Architecture
BTS
BTS
Abis
BSS CS Core
GMSC
PS Core
PSTN
MS
IP
Gn
Gi
Uu
RNC
WCDMA Architecture
MSC
GGSNSGSN
NodeB
Iub
RAN CS Core
GMSC
PS Core
PSTN
MSNodeB
Iu-CS
Iu-PS
RNC
Iur
NodeB IP
Gn
Gi
LTE Architecture PhilosophySingle 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
eNodeB
eNodeB
X2
S1-MME
S1-U S5 / S8
S11
S6a
Gx
PDN
S4
External 3GPP Core Network
SGi
Uu
E-UTRAN EPC
S3
Combined into SAE - GW
eNodeBRRM functions Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic resource allocation UL
& DL
IP header compression and encryption of user data
Selection of MME at UE attachment
Measurements for mobility
Scheduling and transmission of paging and broadcast
Samsung eNodeB: CDU & RRU
L9CA Card
DU
RRU
CPRI
UAMA Card
Samsung Smart SchedulerUses general purpose hardware platform – IBM BladeCenter 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
Mobility Management EntityControl plane Network Element in EPCNon-Access-Stratum (NAS) Security (Authentication, integrity Protection)Tracking Area updatesSubscriber attach/detachSignaling coordination for SAE Bearer Setup/ReleaseRadio Security ControlTrigger and distribution of Paging Messages to eNBRoaming Control (S6a interface to HSS)Inter-CN Node Signaling (S10 interface), allows efficient inter-MME tracking area updates and attaches
Samsung MME
FAN
L
E
S
A
L
E
S
A
L
E
S
A
BLANK
L
E
N
A
L
E
N
A
L
E
M
A
L
E
M
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
FAN
RAID
FAN
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
M
A
L
E
M
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
L
E
S
A
FAN
Item Specification
Capacity/Performance
10M Subscribers, 30M Bearers
36,000 CPS (1 CPS = 1 Attach and 1 Detach per second)
16 x GE
Rack Dimen-sion 600 mm(W) x 800 mm(D) x 2,000 mm(H)
Board
LEMA LTE EPC Management board Assembly : Switch and Management
LENA LTE EPC Network Interface board Assembly : Network interface
LESA LTE EPC Session management board Assembly : Session/Mobility management
RedundancyLEMA, LENA – 1:1 (active/standby)
LESA – 2:1 (active/standby)
Serving GatewayLocal mobility anchor point: Switching the user plane path to a new eNB in case of Handover
Mobility anchoring for inter-3GPP mobility. This is sometimes referred to as the 3GPP Anchor function
Idle Mode Packet Buffering and notification to MME
Packet Routing/Forwarding between eNB, PDN GW and SGSN
Lawful Interception support
PDN GatewayMobility anchor for mobility between 3GPP access systems and non-3GPP access systems. This is sometimes referred to as the SAE Anchor function
Policy Enforcement (PCEF)
Per User based Packet Filtering (i.e. deep packet inspection)Charging & Lawful Interception support
IP Address Allocation for UE
Packet Routing/Forwarding between Serving GW and external Data Network
Packet screening (firewall functionality)
Samsung SAE-GW
FAN
L
E
N
A
L
E
N
A
L
E
N
A
L
E
N
A
L
E
N
A
L
E
N
A
L
E
M
A
L
E
M
A
L
E
D
A
L
E
D
A
L
E
D
A
L
E
D
A
L
E
D
A
L
E
D
A
FAN
RAID
Item Specification
Capacity/Performance
2.8M IP-CAN sessions / 8.4M bearers with full redundancy
100Gbps for only data forwarding with redun-dancy60Gbps including DPI/PCC with redundancy44Gbps including HHE[1]/DPI/PCC with redun-dancy
Simultaneous packet & call processing
16,000 CPS (1 CPS = 1 Attach and 1 Detach per sec)
12 x 40GE and 48 x 10GE
Rack Dimension 600 mm(W) x 800 mm(D) x 2,000 mm(H)
Board
LEMA LTE EPC Management board Assembly : Switch and Management
LENA LTE EPC Network Interface board Assembly : Network interface
LEDA LTE EPC Data Processing board Assembly : Call control
RedundancyLEMA, LENA – 1:1 (active/standby)
LEDA – 2:1 (active/standby)
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 QuantificationMumbai
Zones ( 2)
NP GW
OCS
NP GWMNP GWIMS Apps
eSMLC / GMLCLIM - 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
SummaryLTE 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 Air Interface
Air Interface Features
Air Interface of EUTRAN
OFDMA in downlink and SC-FDMA in Uplink
FDD and TDD duplex methods
Scalable bandwidth 1.4MHz to currently 20MHz
MIMO (Multiple Input Multiple Output) is a major component
LTE Key ParametersFrequency Range UMTS FDD bands and UMTS TDD bands
Channel Band-width, 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 Access Downlink: OFDMAUplink: SC-FDMA
MIMOTransmit diversity, Cyclic delay diversity (Max. 4 antenna at Base station & hand-set)Spatial multiplexing, Multiuser MIMO
Peak Data rateDownlink: 150Mbps (UE category 4, 2x2 MIMO, 20MHz) 300Mbps (UE category 5, 4x4 MIMO, 20MHz) Uplink: 75Mbps (20MHz)
UE Categories
All categories support 20 MHz
2x2 MIMO mandatory in other classes except Class 1
UE Category Class 1 Class 2 Class 3 Class 4 Class 5
Peak Data rate DL (Mbps) 10 50 100 150 300
Peak Data rate UL (Mbps) 5 25 50 50 75
Modulation DL 64QAM 64QAM 64QAM 64QAM 64QAM
Modulation UL 16QAM 16QAM 16QAM 16QAM 64QAM
MIMO DL Optional 2x2 2x2 2x2 4x4
LTE Frequency Variants in 3GPP – FDD
1
2
3
4
5
7
8
9
6
2x25
2x75
2x60
2x60
2x70
2x45
2x35
2x35
2x10
824-849
1710-1785
1850-1910
1920-1980
2500-2570
1710-1755
880-915
1749.9-1784.9
830-840
Total [MHz] Uplink [MHz]
869-894
1805-1880
1930-1990
2110-2170
2620-2690
2110-2155
925-960
1844.9-1879.9
875-885
Downlink [MHz]
10 2x60 1710-1770 2110-2170
11 2x25 1427.9-1452.9 1475.9-1500.9
1800
2600
900
US AWS
UMTS core
US PCS
US 850
Japan 800
Japan 1700
Japan 1500
Extended AWS
Europe Japan Americas
788-798 758-768
777-787 746-756
UHF (TV)
US700
2x10
2x1013
12 2x18 698-716 728-746
14
790-820 832-862?2x30?xx
US700
US700
LTE Frequency Variants - TDD
33
34
35
36
1x60
1x15
1x20
1x60
1850-1910
2010-2025
1900-1920
1930-1990
37
38
1x20
1x50
1910-1930
2570-2620
Total Spectrum
Frequency (MHz)
UMTS TDD1
UMTS TDD2
US PCS
US PCS
US PCS
Euro Middle Gap 2600
39
40
1x40
1x100
1880-1920
2300-2400
China TDD
2.3 TDD
OFDMAFlexible resource allocationRobustness 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 BasicsData 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
uenc
y
•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
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
TSYMB
OL
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 front of 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)
Sub-Carrier Types
• Used for data transmission Data
• Used for channel quality and signal strength estimatesReference Signals
• DC (centre) subcarrier: channel’s centre frequency• Guard subcarriers: Separate top and bottom subcarriers
from any adjacent channel
Null subcarriers (no transmission/power)
Guard (no power)
DC (no power)
data
Guard (no power)
FFT in OFDMFast Fourier Transform (FFT) and the Inverse Fast Fourier Transform (IFFT) allows to move 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 individual users as shown below
S/P IFFT CP
Modulation mapping e.g.
QPSK symbols
Transmitter Receiver
P/SFFTCPRemov
e
Modulation mapping e.g.
QPSK symbols
Total Channel Bandwidth
Transmitted Sub-Carriers
User 1
User 2
User 3
OFDMA Parameters
1.4MHz 3 MHz 5 MHz 10 MHz 15 MHz 20 MHz
Frame Duration 10 ms
Subcarrier Spacing 15 KHz
Sampling Rate (MHz) 1.92 3.84 7.68 15.36 23.04 30.72
Data Subcarriers 72 180 300 600 900 1200
OFDM Symbols/slot Normal CP=7, Extended CP=6
CP length Normal CP=4.69/5.12 μsec, Extended CP= 16.67μsec
OFDMA PAPR RatioThe transmitted power is the sum of the powers of all the subcarriers.
The higher the peaks, the greater the 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
Gua
rdPe
riod
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 the smallest time unit the scheduler assigns to physical channels. In case of TDD there is a time offset between uplink and downlink transmission.
Frame structure type 1
LTE Radio Frames, Slots and Sub frames TDD mode
Frame structure type 2
0 1 2 3 4 5 6 7 8 9TDD 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 Broadcast Channel (BCH)
UL/DL Configuration
Downlink-To-Uplink Switch-Point Periodicity
Subframe Number
0 1 2 3 4 5 6 7 8 90 5 ms D S U U U D S U U U1 5 ms D S U U D D S U U D2 5 ms D S U D D D S U D D3 10 ms D S U U U D D D D D4 10 ms D S U U D D D D D D5 10 ms D S U D D D D D D D6 5 ms D S U U U D S U U D
Flexible Spectrum UsageChannel bandwidth: Bandwidths ranging from 1.4 MHz to 20 MHzData subcarriers: They vary with the bandwidth 72 for 1.4MHz to 1200 for 20MHz
LTE Frame DetailsFrame (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)
…..…..
PSS and SSS
PCID = 3* NID (1) + NID (2) NID (1) = 0,1, …..,167 NID (2) = 0,1,2
Used for scrambling the information from the cell
One of 168 possibilities
Synchronization Signal(PSS & SSS)
. …….
Symbol 0 Symbol 6Symbol 5
1st slot (0.5 ms)
PSSSSS
SSS
Physical layer cell identitygroup
One of three possibilities
PSS
Physical layer identity
10 2
PSS - TD LTEPSS is in Symbol # 2 of Sub-frames 1 and 6
Frame duration =10msec
... …
Sub frame 1
0.5 msec 0.5 msec
Slot 2 Slot 19Slot 3 Slot 18
Sub frame 9Sub frame 6
Slot 12 Slot 13
Single Sub Frame ( Duration=1 msec )
. …. …. ….
0 131 2 PSS 6 9 107 8
…
SSS - TD LTESSS is in Symbol # 13 of Sub-frames 0 and 5
Frame duration =10msec
… …
Sub frame 0
0.5 msec 0.5 msec
Slot 0 Slot 19Slot 1 Slot 18
Sub frame 9Sub frame 5
Slot 10 Slot 11
Single Sub Frame ( Duration=1 msec )
. ..…. …. ….
0 13 SSS1 2 6 9 107 8
System Acquisition
UE Power Up
Identified PSS & SSS,Determined Physical Cell ID
Get Synchronized in both Time and
Frequency
Identify PBCH(4 OFDM symbol x 6 RB’S)
System Information
Obtained through MIB At this stage
UE knows :Channel Bandwidth,SFN , Physical cell ID
No of Antennas
System Acquisition (Continued)
PDSCH(Physical Downlink Shared Channel)
Identify the Location of SIBs
PCFICH (Physical Control Frame Indicator Channel)
PBCH
Presence of CFI field
Identify the OFDMA Symbols used for PDCCH
PDCCH(Physical Downlink Control Channel)
Contains DCI field
Identify the PDSCH Resources Allocation for SIBs
System Information
Block Information
MIB Physical Layer Info
SIB 1 PLMN ID, Tracking Area ID, Access restrictions, SIB scheduling info
SIB 2 Common and shared channel info: SRS, PUSCH, PUCCH, Paging & RACH configuration, UL frequency information
SIB 3 Intra-frequency cell reselection parameters and information
SIB 4 Information on Intra-frequency neighbors
SIB 5 Information on Inter-frequency neighbors
SIB 6 Information for reselection on UTRAN (UMTS) cells
SIB 7 Information for reselection on GERAN (GSM) cells
SIB 8 Information for reselection on CDMA 2000 system
SIB 9 Home eNB information for future femtocells
SIB 10 Primary Earthquake and Tsunami Warning (ETWS) information
SIB 11 Secondary Earthquake and Tsunami Warning (ETWS) information
Summary View of Channel Functions
MIMO
MIMO
Number Of AntennasData Transmission Number Of Users
1. Beam-Forming
(Pre Coding)
2. Spatial
Multiplexing
3. Diversity
Coding
4. SDMA (Spatial Divi-
sion multiple access)
1. SISO (Single input single
output)
2. SIMO (Single input multiple
output)
3. MISO (Multiple input single
output)
4. MIMO (Multiple input single
output)
1. SU-MIMO (Single
User MIMO)
2. MU-MIMO (Multi
User MIMO)
MIMO
Number Of AntennasData Transmission
MIMO Types (Continued)
MIMO
Number Of AntennasData Transmission Number Of Users
1. Beam-Forming
(Pre Coding)
2. Spatial
Multiplexing
3. Diversity
Coding
4. SDMA (Spatial Divi-
sion multiple access)
1. SISO (Single input single
output)
2. SIMO (Single input multiple
output)
3. MISO (Multiple input single
output)
4. MIMO (Multiple input single
output)
1. SU-MIMO (Single
User MIMO)
2. MU-MIMO (Multi
User MIMO)
MIMO
Number Of AntennasData Transmission
UL MIMO
Allocate the same resource blocks to
Multiple UEs
→ Improves spectrum efficiency
Selection of better link antenna
(with single TX RF at the UE)
→ Improves link performance
eNodeB
UE
UE
11h
NMh
1Nh
1MhUE
eNodeB
Multi-user MIMO Antenna selection diversity
SummaryOFDMA allows flexible resource allocation
OFDMA maps one modulation symbol on a subcarrier and transmits multiple subcarriers 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 the allocated 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
Thank You