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Arief Hamdani Gunawan
1.1. Introduction to LTEIntroduction to LTE
2.2. OFDMAOFDMA
3.3. SCSC--FDMAFDMA
4.4. LTE Network and ProtocolLTE Network and Protocol
5. LTE Radio Procedures5. LTE Radio Procedures
6. LTE Uplink Physical Channels and 6. LTE Uplink Physical Channels and
SignalsSignals
7. LTE Mobility7. LTE Mobility
8. LTE Test and Measurement8. LTE Test and Measurement
Arief Hamdani Gunawan
Session 1: Introduction to LTE
•Motivation•Motivation
•Requirements
•Evolution of UMTS FDD and TDD
•LTE Technology Basics
•LTE Key Parameters
•LTE Frequency Bands
Motivation: LTE background storythe early days
Work on LTE was initiated as a 3GPP release 7 study item “Evolved UTRA and UTRAN” in December 2004:
“With enhancements such as HSDPA and Enhanced Uplink, the 3GPP radio-access technology will be highly competitive for several years. However, to ensure competitiveness However, to ensure competitiveness in an even longer time frame, i.e. for the next 10 years and beyond, a long term evolution of the 3GPP radio-access technology needs to be considered.”
• Basic drivers for LTE have been:– Reduced latency– Higher user data rates– Improved system capacity and
coverage– Cost-reduction.
Major requirements for LTEidentified during study item phase in 3GPP
• Higher peak data rates: 100 Mbps (downlink) and 50 Mbps (uplink)
• Improved spectrum efficiency: 2-4 times better compared to 3GPP release 6
• Improved latency:– Radio access network latency (user plane UE – RNC - UE) below 10 ms
– Significantly reduced control plane latency
• Support of scalable bandwidth: 1.4, 3, 5, 10, 15, 20 MHz• Support of scalable bandwidth: 1.4, 3, 5, 10, 15, 20 MHz
• Support of paired and unpaired spectrum (FDD and TDD mode)
• Support for interworking with legacy networks
• Cost-efficiency:– Reduced CApital and OPerational EXpenditures (CAPEX, OPEX) including
backhaul
– Cost-effective migration from legacy networks
• A detailed summary of requirements has been captured in 3GPP TR 25.913 „Requirements for Evolved UTRA (E-UTRA) and Evolved UTRAN (E-UTRAN)”.
Evolution of UMTS FDD and TDDdriven by data rate and latency requirements
Note:
•High-Speed Downlink Packet Access (HSDPA, also known as High-Speed Data Packet Access)
•High-Speed Uplink Packet Access (HSUPA)
•High Speed Packet Access (HSPA)
3GPP Systems
Building on Releases
Release 99: Key Features
• Functional Freeze: Dec 1999
– CS and PS
– R99 Radio Bearers
– Multimedia Messaging Service (MMS)
– Location Services
• Functional Freeze: March 2000
– Basic 3.84 Mcps W-CDMA (FDD & TDD)
• Enhancements to GSM data (EDGE).
• Provides support for GSM/EDGE/GPRS/WCDMA radio-access networks.
• Majority of deployments today are based on Release 99.
Release 4: Key Features
• Functional Freeze: March 2001
– Enhancements 1.28 Mcps TDD (aka TD-SCDMA).
– Multimedia messaging support.
– First steps toward using IP transport in the core
network.
Megachips per second (Mcps) is a measure of the speed with which encoding elements,
called chips (not to be confused with microchips), are generated in Direct Sequence Spread
Spectrum (DSSS) signals. This speed is also known as the chipping rate. A speed of 1 Mcps is
equivalent to 1,000,000, or 106, chips per second.
Typical chipping rates in third-generation (3G) wireless systems are on the order of several
million chips per second. For example, in Wideband Code-Division Multiple Access (W-CDMA)
systems, the standard rate is 3.84 Mcps.
Release 5: Key Features
• Functional Freeze: June 2002
– HSDPA
– IMS: First phase of Internet Protocol Multimedia Subsystem (IMS).
– Adaptive Multi-Rate - Wideband (AMR-WB) Speech
– Full ability to use IP-based transport instead of just Asynchronous
Transfer Mode (ATM) in the core network.Transfer Mode (ATM) in the core network.
Adaptive Multi-Rate Wideband (AMR-WB) is a patented speech coding standard developed
based on Adaptive Multi-Rate encoding, using similar methodology as Algebraic Code Excited
Linear Prediction (ACELP). AMR-WB provides improved speech quality due to a wider speech
bandwidth of 50–7000 Hz compared to narrowband speech coders which in general are
optimized for POTS wireline quality of 300–3400 Hz. AMR-WB was developed by Nokia and
VoiceAge and it was first specified by 3GPP.
AMR-WB is codified as G.722.2, an ITU-T standard speech codec, formally known as Wideband
coding of speech at around 16 kbit/s using Adaptive Multi-Rate Wideband (AMR-WB). G.722.2
AMR-WB is the same codec as the 3GPP AMR-WB. The corresponding 3GPP specifications are TS
26.190 for the speech codec and TS 26.194 for the Voice Activity Detector.
3GPP architecture evolution towards flat architecture
Carrier based HetNet Interference co-ordination for LTE
Carriers in same or different bands in HetNet environments with
mixture of different BTS types
Enhancements to Relays, Mobile Relay for LTE
RF core requirements for relays
Mobile relay: mounted on a vehicle wirelessly connected to the macro
cellsInterworking - 3GPP EPS and fixed BB accesses, M2M, Non voice emergency communications, 8 carrier
HSDPA, Uplink MIMO study
RAN Release 11 Priorities
• Short term prioritization for the end of 2011, between RAN#53 and RAN#54
• The next Plenary - RAN#54 (Dec. 2011) – will discuss priorities beyond March 2012
H S P A Priority Work Items;Latest
WID/SID
RAN
Working Group
Core part: Uplink Transmit Diversity for HSPA – Closed Loop RP-110374 RAN 1
New WI: Four Branch MIMO transmission for HSDPA RP-111393 RAN 1
Core Part: eight carrier HSDPA RP-101419 RAN 1
Core part: Further Enhancements to CELL_FACH RP-111321 RAN 2
New WI: HSDPA Multiflow Data Transmission RP-111375 RAN 2
Proposed WID: Single Radio Voice Call Continuity from UTRAN/GERAN to E-UTRAN/HSPA RP-111334 RAN 3
Core part: Non-contiguous 4C-HSDPA operation RP-110416 RAN 4
New SID proposal: Introduction of Hand phantoms for UE OTA antenna testing RP-111380 RAN 4
Core part: Uplink Transmit Diversity for HSPA – Open Loop RP-110374 RAN 4
UE Over the Air (Antenna) conformance testing methodology- Laptop Mounted Equipment Free Space test RP-111381 RAN 4
RAN Release 11 Priorities
L T E Priority Work Items;Latest
WID/SID
RAN
Working Group
WI/SI Coordinated Multi-Point Operation for LTE RP-111365 RAN 1
Core part: LTE Carrier Aggregation Enhancements RP-111115 RAN 1
Core part: Further Enhanced Non CA-based ICIC for LTE RP-111369 RAN 1
Study on further Downlink MIMO enhancements for LTE-Advanced RP-111366 RAN 1
Provision of low-cost MTC UEs based on LTE RP-111112 RAN 1
Proposed SI on LTE Coverage Enhancements RP-111359 RAN 1
Core part: LTE RAN Enhancements for Diverse Data Applications RP-111372 RAN 2
Study on HetNet mobility enhancements for LTE RP-110709 RAN 2
Enhancement of Minimization of Drive Tests for E-UTRAN and UTRAN RP-111361 RAN 2
New WI: Signalling and procedure for interference avoidance for in-device coexistence RP-111355 RAN 2New WI: Signalling and procedure for interference avoidance for in-device coexistence RP-111355 RAN 2
New WI proposal: RAN overload control for Machine-Type Communications RP-111373 RAN 2
Core part: Service continuity and location information for MBMS for LTE RP-111374 RAN 2
Core Part: Network-Based Positioning Support for LTE RP-101446 RAN 2
Further Self Optimizing Networks (SON) Enhancements RP-111328 RAN 3
Core part: Carrier based HetNet ICIC for LTE RP-111111 RAN 3
New WI: Network Energy Saving for E-UTRAN RP-111376 RAN 3
Proposed WID: LIPA Mobility and SIPTO at the Local Network RAN Completion RP-111367 RAN 3
Study on further enhancements for HNB and HeNB RP-110456 RAN 3
New SI: Mobile Relay for E-UTRA RP-111377 RAN 3
Enhanced performance requirement for LTE UE RP-111378 RAN 4
New SI: Study of RF and EMC Requirements for Active Antenna Array System (AAS) Base Station RP-111349 RAN 4
Study on Measurement of Radiated Performance for MIMO and multi-antenna reception for HSPA and LTE terminals RP-090352 RAN 4
New WI: E-UTRA medium range and MSR medium range/local area BS class requirements RP-111383 RAN 4
Core part: Relays for LTE (part 2) RP-110914 RAN 4
Study on Inclusion of RF Pattern Matching Technologies as a positioning method in the E-UTRAN RP-110385 RAN 4
Plans for LTE-A Release-12
• 3GPP workshop to be held June/2012
– Main themes and strategic directions to be set, e.g.:
• Extreme capacity needs and spectrum efficiency (‘challenge Shannon’
• Flexibility, efficient handling of smartphone diversity
• Offloading to unlicensed radio technologies• Offloading to unlicensed radio technologies
• Power efficiency
• Prime areas of interest, e.g.:– More optimized small cell deployments
Long (16.67/32) (16.67/64) (16.67/128) (16.67/256) (16.67/384) (16.67/512)
LTE – Spectrum Flexibility
• LTE physical layer supports any bandwidth from 1.4 MHz to 20
MHz in steps of 180 kHz (resource block).
• Current LTE specification supports a subset of 6 different
system bandwidths.
• All UEs must support the maximum bandwidth of 20 MHz.• All UEs must support the maximum bandwidth of 20 MHz.
E-UTRA channel bandwidth
Case StudyCase Study
LTE Signal Spectrum (20 MHz case)
59
• The LTE standard uses an over-sized LTE. The actual used bandwidth is controlled by the number of used
subcarriers. 15 kHz subcarrier spacing is the constant factor!
• 18 MHz out of 20 MHz is used for data, 1 MHz on each side is used as guard band.
• LTE used spectrum radio = 90%
• WiMAX used spectrum radio = 82%
TDD & FDD
60
• Time Division Duplex (TDD)
• Frequency Division Duplex (FDD)
• Durasi Frame : 2.5 - 20ms
Tf = 307200 x Ts = 10 ms
Tslot = 15360 x Ts = 0.5 ms
Generic LTE Frame Structure type 1 (FDD)
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• Untuk struktur generik, frame radio 10 ms dibagi dalam 20 slot yang sama berukuran 0.5 ms.
• Suatu sub-frame terdiri dari 2 slot berturut-turut, sehingga satu frame radio berisi 10 sub-frame.
• Ts menunjukkan unit waktu dasar yang sesuai dengan 30.72 MHz.
• Struktur frame tipe-1 dapat digunakan untuk transmisi FDD dan TDD.
LTE Frame Structure type 1 (FDD)
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• 2 slots form one subframe = 1 ms
• For FDD, in each 10 ms interval, all 10 subframes are available for downlink transmission and uplink transmissions.
• For TDD, a subframe is either located to downlink or uplink transmission. The 0th and 5th subframe in a radio frame is
always allocated for downlink transmission.
Downlink LTE Frame Structure type 1 (FDD)
Generic LTE Frame Structure type 2 (TDD)
64
• Struktur frame tipe-2 hanya digunakan untuk transmisi TDD.
• Slot 0 dan DwPTSdisediakan untuk transmisi DL, sedangkan slot 1 dan UpPTS disediakan untuk transmisi
UL.
LTE Frame Structure type 2 (TDD)
65
Mobile WiMAX Frame Structure
66
LTE Frame Structure type 2 (TDD)
DL Peak rates for E-UTRA FDD/TDD frame structure type 1
Downlink
Assumptions
64 QAM
Signal overhead for reference signals and
control channel occupying one OFDM symbol
Unit Mbps in 20 MHz b/s/Hz
Requirement 100 5.0Requirement 100 5.0
2x2 MIMO 172.8 8.6
4x4 MIMO 326.4 16.3
UL Peak rates for E-UTRA FDD/TDDframe structure type 1
Uplink
Assumptions
Single TX UE
Signal overhead for reference signals and control
channel occupying 2RB
Unit Mbps in 20 MHz b/s/Hz
Requirement 50 2.5Requirement 50 2.5
16QAM 57.6 2.9
64QAM 86.4 4.3
Peak rates for E-UTRA TDD frame structure type 2
Downlink Uplink
Assumptions 64 QAM, R=1Single TX UE,
64 QAM, R=1
UnitMbps
in 20 MHzb/s/Hz
Mbps
in 20 MHzb/s/Hz
in 20 MHz in 20 MHz
Requirement 100 5.0 50 2.5
2x2 MIMO in DL 142 7.162.7 3.1
4x4 MIMO in DL 270 13.5
3GPP TR 25.912
Technical Specification Group Radio Access Network;
Feasibility study for
evolved Universal Terrestrial Radio Access (UTRA)
and Universal Terrestrial Radio Access Network (UTRAN)
Release Freeze meeting Freeze date ::Rel-7 RP-33 2006-09-22 ::
event version available
RP-27 0.0.0 2005-03-03
RP-31 0.0.4 2006-03-20
draft 0.1.0 2006-03-20
draft 0.1.1 2006-03-20
post RP-31 0.1.2 2006-03-30
R3-51b 0.1.3 2006-05-02
draft post Shanghai 0.1.4 2006-05-22
draft 0.1.5 2006-07-10
draft 0.1.6 -
draft 0.1.7 2006-05-29
RP-32 0.2.0 2006-06-12
RP-32 7.0.0 2006-06-23
RP-33 7.1.0 2006-10-18
RP-36 7.2.0 2007-08-13
3GPP TR 25.912
Technical Specification Group Radio Access Network;
Feasibility study for
evolved Universal Terrestrial Radio Access (UTRA)
and Universal Terrestrial Radio Access Network (UTRAN)
Rel-8 SP-42 2008-12-11 :: . ETSI
event version available remarks
SP-42 8.0.0 2009-01-02 Upgraded unchanged from Rel-7RTR/TSGR-
0025912v800
Rel-9 SP-46 2009-12-10 ::
Upgraded to Rel-9 with no technical change to enable
reference related to ITU-R IMT-Advanced submission
(reference in 36.912). .
ETSI
(reference in 36.912). .
event version available remarks
RP-45 9.0.0 2009-10-01 Technically identical to v8.0.0RTR/TSGR-
0025912v900
Rel-10 SP-51 2011-03-23 ::Upgraded from previous Release without technical
change .ETSI
event version available remarks
SP-51 10.0.0 2011-04-06 Automatic upgrade from previous Release version 9.0.0RTR/TSGR-
0025912va00
Rel-11 SP-57 2012-09-12 ::Upgraded from previous Release without technical
change .ETSI
event version available remarks
SP-57 11.0.0 2012-09-26 Automatic upgrade from previous Release version 10.0.0 -
Session 3: SC-FDMA
•Introduction SC-FDMA and UL frame structure•Introduction SC-FDMA and UL frame structure
•How to generate SC-FDMA
•How does SC-FDMA signal look like
•SC-FDMA Signal Generation
•SC-FDMA PAPR
•SC-FDMA Parameterization
LTE Uplink Transmission Scheme: SC-FDMA
• Pemilihan OFDMA dianggap optimum untuk memenuhi persyaratan LTE pada arah downlink, tetapi OFDMA memiliki properti yang kurangmenguntungkan pada arah Uplink.
• Hal tsb terutama disebabkan oleh lemahnya peak-to-average power ratio (PAPR) dari sinyal OFDMA, yang mengakibatkan buruknya coverage uplink.
• Oleh karena itu, skema transmisi Uplink LTE untuk mode FDD maupun TDD didasarkan pada SC-FDMA, yang mempunyai properti PAPR lebih baik.
74
didasarkan pada SC-FDMA, yang mempunyai properti PAPR lebih baik.
• Pemrosesan sinyal SC-FDMA memiliki beberapa kesamaan denganpemrosesan sinyal OFDMA, sehingga parameter-parameter DL dan UL dapat diharmonisasi.
• Untuk membangkitkan sinyal SC-FDMA, E-UTRA telah memilih DFT-spread-OFDM (DFT-s-OFDM).
OFDMA and SC-FDMA• The symbol mapping
in OFDM happens in
the frequency
domain.
• In SC-FDMA, the
symbol mapping is
done in the time
domain.
75
domain.
• Appropriate
subscriber mapping
in the frequency
domain allows to
control the PAPR.
• SC-FDMA enable
frequency domain
equalizer approaches
like OFDMA
Comparison of how OFDMA and SC-FDMA
transmit a sequence of QPSK data symbols
76
Creating the time-
domain waveform of an
SC-FDMA symbol
Comparison of how OFDMA and SC-FDMA
transmit a sequence of QPSK data symbols
77
Baseband and shifted
frequency domain
representations of an
SC-FDMA symbol
How to generate SC-FDMA?
• DFT “pre-coding” is performed on modulated data symbols to transform them into frequency domain,
• Sub-carrier mapping allows flexible allocation of signal to available sub-carriers,
• IFFT and cyclic prefix (CP) insertion as in OFDM,
• Each subcarrier carries a portion of superposed DFT spread data symbols, therefore SC-FDMA is also referred to as DFT-spread-OFDM (DFT-s-OFDM).
How does a SC-FDMA signal look like?
• Similar to OFDM signal, but…
– …in OFDMA, each sub-carrier only carries information
related to one specific symbol,
– …in SC-FDMA, each sub-carrier contains information of ALL
transmitted symbols.transmitted symbols.
SC-FDMA signal generationLocalized vs. distributed FDMA
SC-FDMA – Peak-to-average Power Ratio (PAPR)
Comparison of CCDF of PAPR for IFDMA, LFDMA, and OFDMA with M = 256 system subcarriers,
N=64 subcarriers per users, and a = 0.5 roll factor; (a) QPSK; (b) 16-QAM
Source:
H.G. Myung, J.Lim, D.J. Goodman “SC-FDMA for Uplink Wireless Transmission”,
IEEE VEHICULAR TECHNOLOGY MAGAZINE, SEPTEMBER 2006
SC-FDMA parameterization (FDD and TDD)
LTE FDD
•Same as in downlink
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TD-LTE
•Usage of UL depends on the selected UL-DL configuration (1 to 8), each
configuration offers a different number of subframes (1ms) for uplink
transmission,
•Parameterization for those subframes, means number of SC-FDMA symbols
same as for FDD and depending on CP,
Improved UL Performance
SC-FDMA compared to ordinary OFDM
83
Single-carrier transmission in uplink enables low PAPR that gives more 4 dB better link
budget and reduced power consumption compared to OFDM
LTE Uplink SC-FDMA Physical Layer Parameters
84
Physical Channel Processing
• Scrambling: Scramble binary information
• Modulation Mapper: Maps groups of 2, 4, or 6 bits onto QPSK, 16QAM, 64QAM symbol constellation points
85
• Transform Precoder: Slices the input data vector into a set of symbol vectors and perform DFT transformation.
• Resource Element Mapper: Maps the complex constellation points into the allocated virtual resource blocks
and performs translation into physical resource blocks.
• SC-FDMA Signal Generation: Performs the IFFT processing to generate final time domain for transmission.
Single Carrier
Constellation
Mapping
S/P
Convert
M-Point
DFT
Subcarrier
MappingN-Point
IDFT
Cyclic
Prefix &
Pulse
Shaping
RFEBit
Stream
Channel
Symbol
Block
SC-FDMA and OFDMA Signal Chain
Have a High Degree of Functional Commonality
86
Const.
De-mapS/P
Convert
M-Point
IDFT
Freq
Domain
Equalizer
N-Point
DFT
Cyclic
Prefix
RemovalRFE
Bit
Stream
Symbol
Block
SC
Detector
Functions Common to OFDMA and SC-FDMA
SC-FDMA Only
Session 4: Network and Protocol
•Network architecture•Network architecture
•Protocol Stack – User plane
•Protocol Stack – Control plane
•Mapping between logical and transport channel
•LTE UE Categories
LTE Network Architecture
GGSN
UMTS 3G: UTRAN
SGSN
MMEMME
SS--GW / PGW / P--GWGW
MMEMME
SS--GW / PGW / P--GWGW
EPC
UMTS : Universal Mobile Telecommunications System
UTRAN : Universal Terrestrial Radio Access Network
GGSN : Gateway GPRS Support Node
GPRS: General Packet Radio Service
SGSN : Serving GPRS Support Node
RNC: Radio Network Controller
NB: Node B
RNC RNC
NB NB NB NB
eNB
eNB eNB
eNB
E-UTRAN
EPC ; Evolved Packet Core
MME : Mobility Management Entity
S-GC : Serving Gateway
P-GW : PDN Gateway
PDN : Packet Data Network
eNB : E-UTRAN Node B / Evolved Node B
E-UTRAN ; Evolved-UTRAN
Simplified LTE network elements and interfaces3GPP TS 36.300 : Overall Architecture
MMEMME
SS--GW / PGW / P--GWGW
MMEMME
SS--GW / PGW / P--GWGW
EPC
EPC: Evolved Packet Core
Radio Side: LTE – Long Term Evolution
• Improvements in spectral efficiency, user
throughput, latency.
• Simplification of the radio network
• Efficient support of packet services
• Main Components:• MME = Manages mobility, UE identity, and
security parameters.
• S-GW = Node that terminates the interface
towards E-UTRAN.S1
eNB
eNB eNB
eNB
E-UTRAN
towards E-UTRAN.
• P-GW = Node that terminates the interface
towards PDN
E-UTRAN : Evolved-UTRAN
Network Side : SAE – System Architecture Evolution
• Improvement in latency, capacity, throughput
• Simplification of the core network
• Optimization for IP traffic services
• Simplified support and handover to non-3GPP
access technologies
• Main Components: • eNB = All radio interface-related functions
X2
S-GW P-GW
MME
Operator’s
IP ServicesLTE-Uu SGi
RxGx
S5 / S8
S6a
S1-MME
S1-U
EPS Network Elements
E-UTRAN EPC
• UE, E-UTRAN and EPC together represent the Internet Protocol (IP) Connectivity Layer.
• This part of the system is also called the Evolved Packet System (EPS).
• The main function of this layer is to provide IP based connectivity, and it is highly optimized for that purpose only.
• All services will be offered on top of IP, and circuit switched nodes and interfaces seen in earlier 3GPP architectures are not present in E-UTRAN and EPC at all.
• IP technologies are also dominant in the transport, where everything is designed to be operated on top of IP transport.
eNB
UE
S-GW P-GW IP Services
(e.g. IMS, PSS, etc,)
LTE-Uu SGiS5 / S8S1-U
System architecture for E-UTRAN only network
Services
• The IP Multimedia Sub-System
(IMS) is a good example of service
machinery that can be used in the
Services Connectivity Layer to
provide services on top of the IP
connectivity provided by the connectivity provided by the
lower layers.
• For example, to support the voice
service, IMS can provide Voice
over IP (VoIP) and
interconnectivity to legacy circuit
switched networks PSTN and
ISDN through Media Gateways it
controls.
EPC
• Functionally the EPC is equivalent to the packet switched domain of the existing 3GPP networks.
• Significant changes in the arrangement of functions and most nodes and the architecture in this part should be considered to be completely new.
• SAE GW represents the combination of the two gateways, Serving Gateway (S-GW) and Packet Data Network Gateway (P-GW) defined for the UP handling in EPC.
• Implementing them together as the SAE GW represents one possible deployment scenario, but represents one possible deployment scenario, but the standards define the interface between them, and all operations have also been specified for when they are separate.
• The Basic System Architecture Configuration and its functionality are documented in 3GPP TS 23.401.
• We will learn the operation when the S5/S8 interface uses the GTP protocol. However, when the S5/S8 interface uses PMIP, the functionality for these interfaces is slightly different, and the Gxc interface also is needed between the Policy and Charging Resource Function (PCRF) and S-GW.
One of the big architectural changes in the core network area is that the EPC does not contain a circuit switched domain, and no direct connectivity to traditional circuit switched networks such as ISDN or PSTN is needed in this layer.
E-UTRAN
• The development in E-UTRAN is
concentrated on one node, the
evolved Node B (eNodeB).
• All radio functionality is collapsed
there, i.e. the eNodeB is the
termination point for all radio
related protocols. related protocols.
• As a network, E-UTRAN is simply
a mesh of eNodeBs connected to
neighbouring eNodeBs with the
X2 interface.
User Equipment
• UE is the device that the end user uses for
communication.
• Typically it is a hand held device such as a smart
phone or a data card such as those used
currently in 2G and 3G, or it could be
embedded, e.g. to a laptop.
• UE also contains the Universal Subscriber
Identity Module (USIM) that is a separate
module from the rest of the UE, which is often module from the rest of the UE, which is often
called the Terminal Equipment (TE).
• USIM is an application placed into a removable
smart card called the Universal Integrated
Circuit Card (UICC).
• USIM is used to identify and authenticate the
user and to derive security keys for protecting
the radio interface transmission.
• Maybe most importantly, the UE provides the
user interface to the end user so that
applications such as a VoIP client can be used to
set up a voice call.
Functionally the UE is a platform for communication
applications, which signal with the network for setting
up, maintaining and removing the communication links
the end user needs.
This includes mobility management functions such as
handovers and reporting the terminals location, and in
these the UE performs as instructed by the network.
User Equipment Capabilities
• Support Spectrum flexibility– Flexible bandwidth
Technical Specification Group Radio Access Network;Evolved Universal Terrestrial Radio Access (E-UTRA);
User Equipment (UE) radio access capabilities
MIMO = Multiple Input Multiple Output
UL-SCH = Uplink Shared Channel
DL-SCH = Downlink Shared Channel
UE = User Equipment
TTI = Transmission Time Interval
Transmission Time Interval
• Transmission Time Interval: Transmission Time Interval is defined as the inter-arrival time of Transport Block Sets, i.e. the time it shall take to transmit a Transport Block Set.
• Transport Block Set: Transport Block Set is defined as a set of Transport Blocks that is exchanged between L1 and MAC at the same time instance using the same transport channel. An the same time instance using the same transport channel. An equivalent term for Transport Block Set is “MAC PDU Set”.
• Transport Block: Transport Block is defined as the basic data unit exchanged between L1 and MAC. An equivalent term for Transport Block is “MAC PDU”.
Technical Specification Group Radio Access Network;Evolved Universal Terrestrial Radio Access (E-UTRA);
User Equipment (UE) radio access capabilities
eNB
Functional split between E-UTRAN and Evolved Packet Core
E-UTRAN
aGW
• Paging origination
• LTE_IDLE mode management
• Ciphering of the user plane
• Header Compression (ROHC)
eNodeB
• All Radio-related issues
• Decentralized mobility
management
• MAC and RRM
• Simplified RRC
aGW
Internet
S1
The E-UTRAN consists of eNBs, providing:
• The E-UTRA U-plane (RLC/MAC/PHY) and
• The C-plane (RRC) protocol terminations
towards the UE.
• The eNBs interface to the aGW via the S1
RRM : Radio Resource Management
RRC: Radio Resource Control
MAC : Medium Access Control
ROHC: RObust Header Compression
RLC: Radio Link Control
PHY: Physical Layer
eNB
Protocol
Inter Cell RRM
RB Cont.
Connection Mobility Cont.
Radio Admission Cont.
eNB Measurement
Configuration & Provision
Dynamic Resource
Allocation (Scheduler)
MME
NAS Security
Idle State Mobility Handling
EPS Bearer Cont.
SAE GW
EPC
E-UTRAN
RRM : Radio Resource Management
RB : Radio Bearer
RRC: Radio Resource Control
PDCP : Packet Data Convergence Protocol
RLC : Radio Link Control
MAC : Medium Access Control
PHY : Physical Layer
Allocation (Scheduler)
RRC
PDCP
RLC
MAC
PHY
UE IP Address
Allocation
Packet Filtering
P-GW
Mobile Anchoring
S-GW
SAE GW
NAS : Non Access Stratum
EPS : Evolved Packet System
UE : User Equipment
IP : Internet Protocol
Internet
S1
eNB
LTE Control Plane
NAS
RRC
PDCP
RLC
MAC
PHY
S1
UE
RRC
PDCP
RLC
MAC
PHY
NAS
aGW Non Access Stratum (NAS) is a
functional layer in UMTS
protocol stack between Core
Network and User Equipment
(UE).
The layer supports signaling and
traffic between two elements.
eNB
LTE User Plane
IP
PDCP
RLC
MAC
PHY
S1
UE
PDCP
RLC
MAC
PHY
IP
aGW
Packet Data Convergence Protocol
(PDCP) is a one of the layers of
Radio Traffic Stack in UMTS
and perform as IP header
compression and
decompression, transfer of
user data and maintenance of
sequence numbers for Radio
Bearers which are configured
for lossless Serving Radio
Networks Subsystems (SRNS)
relocation.
LTE Protocol Stacks (UE and eNB)
RRC: Radio Resource Control
PDCP : Packet Data Convergence Protocol
RLC : Radio Link Control
MAC : Medium Access Control
PHY : Physical Layer
RRC
PDCP
Control-Plane
L3
User-Plane
L2
Radio Bearers
RLC
MAC
PHY:
Physical Channels
Physical Signals
L1
Transport Channels
Logical Channels
Control plane protocol stack in EPS
The topmost layer in the CP is the Non-Access Stratum (NAS), which consists of two
separate protocols that are carried on direct signaling transport between the UE
and the MME.
The content of the NAS layer protocols is not visible to the eNodeB, and the eNodeB is
not involved in these transactions by any other means, besides transporting the
messages, and providing some additional transport layer indications along with the
messages in some cases.
NAS layer protocolsThe NAS layer protocols are:
• EPS Mobility Management (EMM): The EMM protocol is responsible for handling the UE mobility within the system. It includes functions for attaching to and detaching from the network, and performing location updating in between. This is called Tracking Area Updating (TAU), and it happens in idle mode. Note that the handovers in connected mode are handled by the lower layer protocols, but the EMM layer does include functions for re-activating the UE from idle mode. The UE initiated case is called Service Request, while Paging represents the network initiated case. Authentication and protecting the UE identity, i.e. allocating the initiated case. Authentication and protecting the UE identity, i.e. allocating the temporary identity GUTI to the UE are also part of the EMM layer, as well as the control of NAS layer security functions, encryption and integrity protection.
• EPS Session Management (ESM): This protocol may be used to handle the bearer management between the UE and MME, and it is used in addition for E-UTRAN bearer management procedures. Note that the intention is not to use the ESM procedures if the bearer contexts are already available in the network and E-UTRAN procedures can be run immediately. This would be the case, for example, when the UE has already signaled with an operator affiliated. Application Function in the network, and the relevant information has been made available through the PCRF.
User plane protocol stack in EPS
The UP includes the layers below the end user IP, i.e. these protocols form the Layer 2
used for carrying the end user IP packets.
The protocol structure is very similar to the CP.
This highlights the fact that the whole system is designed for generic packet data
transport, and both CP signaling and UP data are ultimately packet data. Only the