UMTS Architecture Overview

Chia sẻ: Đỗ TRọng Hậu | Ngày: | Loại File: PPT | Số trang:359

Thêm vào BST

Báo xấu

74
lượt xem 7
download

Download Vui lòng tải xuống để xem tài liệu đầy đủ

A PLMN can be regarded as an independent telecommunications entity. ▪ A PLMN is defined as: ▫ One or more switches with: ▫ Switches act as the interface to ▪ a common numbering plan ▪ a common routing plan external networks ▪ The PLMN can be separated into ▫ Core Network ▫ Access Network

Chủ đề:

Bình luận(0) Đăng nhập để gửi bình luận!

Lưu

Nội dung Text: UMTS Architecture Overview

UMTS Architecture Overview by Dr Paul Raby
System Architecture Overview Public Land Mobile Network (PLMN) ▪ A PLMN can be regarded as an independent telecommunications entity. ▪ A PLMN is defined as: ▫ One or more switches with: Core Network ▪ a common numbering plan ▪a common routing plan ▫ Switches act as the interface to PLMN external networks ▪ The PLMN can be separated into Access Network ▫ Core Network ▫ Access Network
System Architecture Overview UMTS High Level Architecture UMTS Terrestrial User Equipment Core Network Radio Access Network UE UTRAN CN UU IU
System Architecture Overview Major Network Elements in UMTS Node B Radio Network Iu-cs Mobile Switching Gateway Controller Centre MSC PLMN, UMTS SIM RNC MSC/VLR GMSC Node B PSTN, USIM IUb ISDN CU IUr Home Location Register Mobile Equipment HLR ME IUb Internet, X25 Node B Packet Radio Network Gateway Network UE Controller Serving GSN GSN UU Node B RNC Iu-ps SGSN GGSN UTRAN CN IU
System Architecture Overview General UTRAN Architecture Node B Iu-cs Radio Network Controller CN (MSC) RNC Node B IUb IUr UE IUb Node B Radio Network Controller CN (SGSN) RNC Node B Iu-ps UTRAN UU IU
System Architecture Overview Elements of UTRAN ▪ Radio Network Controller ▫ Owns and controls radio resources in its domain (BSC in GSM) ▫ Service Access Point for all services that UTRAN provides for the CN ▫ Note: Service RNC (SRNC) and Drift RNC (DRNC) are subsets ▫ Note: Control RNC (CRNC ) whichever RNC is talking to the UE ▪ Node B ▫ Acts as the radio base station (BTS in GSM) ▫ Converts the data flow between the Iub and Uu interfaces
System Architecture Overview Major Interfaces in UMTS ▪ There are four major new interfaces defined in UMTS CN ▫ Iu Iu ▪The interface between UTRAN and the CN Iur ▫ Iur RNC RNC ▪The Interface between different RNCs Iub ▫ Iub Node- ▪The interface between the Node B and the RNC B ▫ Uu Uu ▪The air interface UE
System Architecture Overview UMTS Interface Implementation SGSN Node B ATM/IP Network MSC RNC Node Iub B Iu_cs Iu_ps Node Node Iur RNC B B
System Architecture Overview Handover in UMTS ▪ There are 3 basic types of handover ▫ Intra frequency handovers ▪ Handovers between 2 UMTS carriers at the same frequency ▪ These can be soft handovers ▫ Inter frequency handovers ▪ Handovers between 2 UMTS carriers at different frequencies ▪ These are hard handovers ▫ Inter system handovers ▪ Handovers between UMTS and GSM carriers ▪ These are hard handovers
System Architecture Overview Macrodiversity between Node B’s Iu ▪ If Active Set consists of ▫ two connections to cells Iur parented to different Node Bs RNC ▫ then the combining of the two channels occurs at the RNC ▪ This is known as a soft handover Node Node ▪ This doubles the B B transmission ‘cost’ of the call Cell Cell Cell Cell Cell Cell Uu
System Architecture Overview Maximal Combining between Cells on the Same Node B ▪ If Active Set consists of Iu ▫ two connections to cells parented to the same Node B Iur ▫ then the combining of the two channels occurs at the RNC Node B ▪ This is known as a softer handover Node Node ▪ This has no transmission implication (but does have B B capacity implications) if cells are collocated. Cell Cell ▪ Uses maximal combining ▫ Adds electrically the Cell Cell Cell Cell signals making one better than each individual Uu
System Architecture Overview Architecture of a UMTS bearer service Each bearer service on a specific layer provides services using layers below. TE CN CN UE UTRAN gateway TE edge node End-to-End TE/UE Local Bearer UMTS Bearer External Bearer Radio Access Bearer CN Bearer Radio Bearer Iu Bearer Backbone Network UTRA FDD/TDD Physical Bearer
System Architecture Overview UMTS Protocol Stratums Non Access Stratum L7 L7 ▪ Non-access Stratum → Encompasses layers 4 to L6 L6 7 of the OSI 7 layer model, and the upper part of layer 3 L5 L5 L4 L4 • Access Stratum L3 upper L3 upper Access Stratum L3 lower L3 lower L3 lower L3 lower → Encompasses layers 1 and 2 of the OSI 7 layer L2 L2 L2 L2 model and the lower part of layer 3 L1 L1 L1 L1 Uu UE UTRAN Iu CN
System Architecture Overview UMTS QoS Classes ▪ Conversational ▫ Speech over CS bearer ▫ Voice over IP, PS bearer ▫ Delay critical, imposed by human perception ▪ Streaming ▫ Multimedia streaming ▫ Using buffers, for non-real time delivery; real-video, real- audio ▪ Interactive ▫ Web browsing, database retrieval ▫ Round trip delay time is a key parameter ▪ Background ▫ E-mail ▫ Delay:- 10s of seconds or even minutes
System Architecture Overview Protocol Model for UTRAN Interfaces ▪ Protocol structures in UTRAN are designed in layers and planes. ▪ They are seen as logically independent of each other ▫ However they will physically interact. ▪ Being logically independent allows for changes to blocks in the future theoretically!
System Architecture Overview General Protocol Model for UTRAN Terrestrial Interfaces
System Architecture Overview Horizontal Layers in the General Protocol Model ▪ All UTRAN related issues are only visible in the Radio Network Layer ▪ The Transport Layer simply represents standard transport technology for use in UTRAN ▫ e.g. ATM and appropriate ATM Adaptation Layers ▪ AAL2 ( voice ) and AAL5 ( data/control) ▫ UDP/IP or RTP/UDP/IP ( release 6 ? )
System Architecture Overview Vertical Planes in the General Protocol Model ▪ The Control Plane is provided for all UMTS specific control signalling including: ▫ Application Protocols ▫ Signalling Bearers ▪ The User Plane is provided for all data sent and received by the user including: ▫ Data Streams ▫ Data Bearers
System Architecture Overview Vertical Planes in the General Protocol Model ▪ The Transport Network Control Plane also includes the Access Link Control Application Part, ALCAP. Transport Transport Network User Transport Network User Plane Network Control Plane Plane ALCAP
UMTS Technology Overview