LTE Signalling - On-Line

LTE Signalling - On-Line

The course contains detailed information about the evolved radio access network (E-UTRAN) introduced in 3GPP Release 8 as part of the Evolved Packet System (EPS). Special attention is given to the radio interface layer 2 and layer 3 protocols as well as the physical layer control channels.

The layer 3 protocols defined for the X2, S1 and S11-interfaces are also covered. The scheduling mechanisms and Hybrid-ARQ (HARQ) functionality for both downlink and uplink are described. Message flows for selected important signalling procedures are investigated step by step, looking at each message and its contents in detail.

The course also contains a description of some expected interworking scenarios (e.g. E-UTRAN to UTRAN handover).MIMO. Basic message-level traffic cases are shown throughout the course to demonstrate important functions and concepts.

E-UTRAN Introduction
•    New network nodes, interfaces, areas, bearer concepts and identity numbers introduced for EPS
•    E-UTRA frequency bands and UE capabilities
•    Current status of the EPS standardisation process

E-UTRAN Protocol Architecture
•    Logical, Transport and Physical channels and their relation to the radio interface protocol stack
•    X2, S1 and S11-interface protocol stacks

E-UTRA Layer 3 Protocols (NAS and RRC)
•    Non Access Stratum protocols and procedures (EMM and ESM)
•    Idle mode mobility mechanisms
•    NAS security mechanisms
•    Radio Resource Control (RRC) procedures
•    UE states and state transitions (NAS and RRC)

Packet Data Convergence Protocol (PDCP)
•    PDCP functionality for Control and User Plane
•    PDCP security mechanisms, including key derivation functions and security algorithms
•    PDCP ARQ functionality at handover
•    PDCP PDU format for Data and Control

Radio Link Control Protocol (RLC)
•    RLC modes and associated PDU formats
•    RLC ARQ mechanism
•    RLC control procedures and control PDUs

Medium Access Control Protocol (MAC)
•    MAC functionality in UE and eNodeB
•    MAC PDU formats for data transmission
•    MAC Control PDUs

E-UTRA Scheduling and HARQ
•    Scheduling Requests and Buffer Status reports
•    Dynamic scheduling for Non Real-time services
•    Persistent scheduling for Real-time services
•    Implicit and explicit UL grants
•    Hybrid-ARQ type I, II and III
•    Incremental Redundancy and selection of Redundancy Version through rate matching
•    HARQ processes and ACK/NACK timing

E-UTRA Physical Layer
•    E-UTRA refresh: modulation, OFDM basics and channel-to-resource mapping
•    UL and DL physical channels for data and L1/L2 control signalling
•    Mapping of control channels onto Control Channel Elements (CCE) and Resource Element Groups
•    PDCCH and PUCCH formats
•    PDCCH candidates and search spaces
•    Determination of MCS and TB size
•    Channel coding for the DL-SCH, including Turbo coding and HARQ rate matching

The S1 and S11-Interface
•    S1 Application Protocol (S1AP) procedures
•    The GTP version 2 protocol (eGTP)
•    EPS QoS mechanisms: default and dedicated bearers, Traffic Flow Templates and QCI values

The X2-Interface
•    X2 Application Protocol (X2AP) procedures
•    Data forwarding and in-order delivery of data PDUs at handover

Interworking
•    Interworking with legacy R8 or pre-R8 3GPP networks
•    Interworking with non-3GPP access networks
•    Overview of various solutions for interworking with the CS domain

E-UTRAN Signalling Procedures
•    The random access procedure
•    RRC connection establishment
•    Attach procedure, including establishment of Default EPS bearer and security associations.
•    Dedicated EPS bearer establishment and interaction with Policy and Charging Control (PCC)
•    Handover with data forwarding via X2-interface
•    Handover with data forwarding via S1-interface
•    Inter-RAT handover with data forwarding via the S12-interface (Direct Tunnel)