UMTS overview Tong quan mang 3G

Prep: Vikash GuptaAppr: Sukhpreet Singh Checked: Rev: PA1 Date: 2016-08-30 UMTS OVERVIEW Ericsson Internal 1 81 1 Development of Mobile communication AMPS = Advanced Mobile phone servi

Trang 1

Prep: Vikash Gupta

Appr: Sukhpreet Singh

Checked:

Rev: PA1 Date: 2016-08-30

UMTS OVERVIEW Ericsson Internal

1 (81)

1

Development of Mobile communication

AMPS = Advanced Mobile phone service GSM=Global system for Mobile Communications TACS=Total Access Communications Systems D-AMPS=Digital-AMPS

NMT= Nordic Mobile Telephone PDC=personal digital cellular

1st Generation 1980s (analog)

current (digital)

AMPS

Analog to Digital

TACS NMT OTHERS

GSM CDMA IS95

Trang 2

History of 3G

 Based on the IMT-200 performance objectives and frequency allocation the ITU-R formally requested a submission

of RTT proposals with a closing date at the end of July 1998

 By the closing date , there were a total of 10 RTT proposals were submitted from Europe , United states , Japan , Korea and, China All these proposal where accepted

 Five RTT for IMT2000

Trang 3

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

Trang 4

Frequency allocation for IMT2000

2170 2110

MSSUMTS

Trang 5

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

Trang 6

UMTS FDD and TDD

FDD (Frequency Division Duplex)

TDD (Time Division Duplex)

Base stationMobile Terminal

Trang 7

Checked:

Rev: PA1 Date: 2016-08-30

7 (81)

Trang 9

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

9 (81)

UTRAN Architecture

Trang 10

UTRAN Architecture

Trang 11

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

Trang 12

UMTS Network Architecture

The UMTS network architecture can be divided into three main elements:

User Equipment (UE): The User Equipment or UE is the name given to what was previous termed the mobile, or cellphone The new name was

chosen because the considerably greater functionality that the UE could have It could also be anything between a mobile phone used for talking to

a data terminal attached to a computer with no voice capability

Radio Network Subsystem (RNS): The RNS is the equivalent of the previous Base Station Subsystem or BSS in GSM It provides and manages

the air interface fort he overall network

Core Network: The core network provides all the central processing and management for the system It is the equivalent of the GSM Network

Switching Subsystem or NSS

The core network is then the overall entity that interfaces to external networks including the public phone network and other cellular

telecommunications networks

Trang 13

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

UE RF circuitry: The RF areas handle all elements of the signal, both for the receiver and for the transmitter One of the major challenges for the

RF power amplifier was to reduce the power consumption The form of modulation used for W-CDMA requires the use of a linear amplifier These inherently take more current than non linear amplifiers which can be used for the form of modulation used on GSM Accordingly to maintain battery life, measures were introduced into many of the designs to ensure the optimum efficiency

Baseband processing: The base-band signal processing consists mainly of digital circuitry This is considerably more complicated than that used

in phones for previous generations Again this has been optimised to reduce the current consumption as far as possible

Trang 14

Battery: While current consumption has been minimised as far as possible within the circuitry of the phone, there has been an increase in current

drain on the battery With users expecting the same lifetime between charging batteries as experienced on the previous generation phones, this has necessitated the use of new and improved battery technology Now Lithium Ion (Li-ion) batteries are used These phones to remain small and

relatively light while still retaining or even improving the overall life between charges

Universal Subscriber Identity Module, USIM: The UE also contains a SIM card, although in the case of UMTS it is termed a USIM (Universal

Subscriber Identity Module) This is a more advanced version of the SIM card used in GSM and other systems, but embodies the same types of information It contains the International Mobile Subscriber Identity number (IMSI) as well as the Mobile Station International ISDN Number

(MSISDN) Other information that the USIM holds includes the preferred language to enable the correct language information to be displayed,

especially when roaming, and a list of preferred and prohibited Public Land Mobile Networks (PLMN)

The USIM also contains a short message storage area that allows messages to stay with the user even when the phone is changed Similarly "phone book" numbers and call information of the numbers of incoming and outgoing calls are stored

The UE can take a variety of forms, although the most common format is still a version of a "mobile phone" although having many data capabilities Other broadband dongles are also being widely used

Trang 15

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

15 (81)

UMTS Radio Network Subsystem

This is the section of the UMTS / WCDMA network that interfaces to both the UE and the core network The overall radio access network, i.e

collectively all the Radio Network Subsystem is known as the UTRAN UMTS Radio Access Network

The Radio Network Subsystem comprises two main components:

Radio Network Controller, RNC: This element of the radio network subsystem controls the Node Bs that are connected to it The RNC undertakes

the radio resource management and some of the mobility management functions, although not all It is also the point at which the data encryption / decryption is performed to protect the user data from eavesdropping

Node B: Node B is the term used within UMTS to denote the base station transceiver It contains the transmitter and receiver to communicate with

the UEs within the cell

In order to facilitate effective handover between Node Bs under the control of different RNCs, the RNC not only communicates with the Core

Network, but also with neighbouring RNCs

Trang 16

UMTS Core Network

The UMTS core network architecture is a migration of that used for GSM with further elements overlaid to enable the additional functionality demanded by UMTS

In view of the different ways in which data may be carried, the UMTS core network may be split into two different areas:

Circuit switched elements: These elements are primarily based on the GSM network entities and carry data in a circuit switched manner, i.e a

permanent channel for the duration of the call

Packet switched elements: These network entities are designed to carry packet data This enables much higher network usage as the capacity

can be shared and data is carried as packets which are routed according to their destination

Some network elements, particularly those that are associated with registration are shared by both domains and operate in the same way that they did with GSM

Trang 17

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

17 (81)

Circuit switched elements

The circuit switched elements of the UMTS core network architecture include the following network entities:

Mobile switching centre (MSC): This is essentially the same as that within GSM, and it manages the circuit switched calls under way

Gateway MSC (GMSC): This is effectively the interface to the external networks

Packet switched elements

The packet switched elements of the UMTS core network architecture include the following network entities:

Serving GPRS Support Node (SGSN): As the name implies, this entity was first developed when GPRS was introduced, and its use has been

carried over into the UMTS network architecture The SGSN provides a number of functions within the UMTS network architecture

Mobility management When a UE attaches to the Packet Switched domain of the UMTS Core Network, the SGSN generates MM

information based on the mobile's current location

Session management: The SGSN manages the data sessions providing the required quality of service and also managing what are termed the PDP (Packet data Protocol) contexts, i.e the pipes over which the data is sent

Interaction with other areas of the network: The SGSN is able to manage its elements within the network only by communicating with other areas of the network, e.g MSC and other circuit switched areas

Trang 18

Billing: The SGSN is also responsible billing It achieves this by monitoring the flow of user data across the GPRS network CDRs (Call Detail Records) are generated by the SGSN before being transferred to the charging entities (Charging Gateway Function, CGF)

Gateway GPRS Support Node (GGSN): Like the SGSN, this entity was also first introduced into the GPRS network The Gateway GPRS

Support Node (GGSN) is the central element within the UMTS packet switched network It handles inter-working between the UMTS packet switched network and external packet switched networks, and can be considered as a very sophisticated router In operation, when the GGSN receives data addressed to a specific user, it checks if the user is active and then forwards the data to the SGSN serving the particular UE

Trang 19

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

19 (81)

Shared elements

The shared elements of the UMTS core network architecture include the following network entities:

Home location register (HLR): This database contains all the administrative information about each subscriber along with their last known

location In this way, the UMTS network is able to route calls to the relevant RNC / Node B When a user switches on their UE, it registers with the network and from this it is possible to determine which Node B it communicates with so that incoming calls can be routed appropriately Even when the UE is not active (but switched on) it re-registers periodically to ensure that the network (HLR) is aware of its latest position with their current or last known location on the network

Equipment identity register (EIR): The EIR is the entity that decides whether a given UE equipment may be allowed onto the network Each UE

equipment has a number known as the International Mobile Equipment Identity This number, as mentioned above, is installed in the equipment and is checked by the network during registration

Authentication centre (AuC) : The AuC is a protected database that contains the secret key also contained in the user's USIM card

Trang 20

QoS of Different Services

Trang 21

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

- The bit rate of AMR voice can be controlled by the RAN according to the payload

of air interface and the quality of voice service

 The requirement of time delay is similar to the voice service

 The CS connection :adopt ITU-T Rec.H.324M (AMR-H.263)

 The PS connection :adopt IETF SIP or H.323

Trang 23

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

23 (81)

23

Summary

Trang 25

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

25 (81)

UMTS FDD Frame Structure

Trang 27

Checked:

Rev: PA1 Date: 2016-08-30

27 (81)

Trang 29

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

29 (81)

Multiple access method CDMA TDMA, CDMA

Channel spacing 5 MHz 5 MHz (and 1.6MHz for TD-SCDMA)

Carrier chip rate 3.84 Mcps 3.84 Mcps Spreading factors 4 512 1 16 Time slot structure 15 slots / frame 15 / 14 slots / frame Frame length (ms) 10 10

Multirate concept Multicode, and OVSF[1] Multicode, multislot and OVSF[1]

Burst types N/A

(1) traffic bursts (2) random access burst (3) synchronisation burst

Detection Coherent based on pilot symbols Coherent based on mid-amble

Dedicated channel power control Fast closed loop 1500 Hz rate Uplink: open loop 100 Hz or 200 Hz rate

Downlink: closed loop max 800 Hz rate

Key Specifications for UTRAN Operation for FDD & TDD

Trang 30

Handovers Hard, Soft , Softer Hard

Trang 31

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

31 (81)

WCDMA Protocol stack OR WCDMA OSI model

Physical channels (Code,frequency,etc)

Logical channels (What is transmitted)

Transport channels (How it is transmitted)Radio Resource Control (RRC)

Physical LayerMedium Access Control (MAC)

Trang 32

 Channels are simply a tool for specifying and describing the various communication and data related services Various type of data is exchanged between UE and base station over the radio channel To characterize this different type of data , we refer to different channels.

There are 3 different types of channels in WCDMA –

1 Logical channels : Used for communication between Layer 3

(RRC) & Layer 2 (RLC/MAC) Depending on the information

content ,logical channels are characterized into traffic & Control

channels.

WCDMA CHANNELS

Trang 33

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

33 (81)

Control Channel (Signaling)

Broadcast Control Channel (BCCH)

Paging Control Channel (PCCH)

Dedicated Control Channel (DCCH)

Common Control Channel (CCCH)

Traffic Channel (User Data)

Dedicated Traffic (DTCH)

Common Traffic Channel (CTCH)

LOGICAL CHANNELS

Trang 34

 Broadcast control channel ( BCCH) : Point to multipoint ,DL

It is a broadcasting channel that supplies all the UE’s with basic cell and network parameters(eg Frequency lists , code lists etc).

 Paging control channel(PCCH) : Point to multipoint ,DL

It transports paging information.

All the UE’s are required to regularly read the information on the

BCCH and on the PCCH

 Dedicated control channel (DCCH) : Point to point ,UL/DL

DCCH is provided in parallel to a DTCH for point to point signaling during an active connection

 Common control channel ( CCCH) : Point to multipoint ,UL/DL

It enables access by a UE to the UTRAN

Control channels

Trang 35

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

35 (81)

 Dedicated traffic channel (DTCH): Point to point ,UL/DL

DTCH is used to transport user data from Node B to a specific UE and vice versa This means it is “dedicated” to a specific subscriber

 Common traffic channel (CTCH) : Point to multipoint ,DL

It transfers dedicated user information for all , or a group of specified UE’s

TRAFFIC CHANNELS:

Trang 36

 Characterizes “HOW” data is transported over the air interface Each transport channel is accompanied by the Transport format indicator(TFI) The physical layer combines the TFI information of different transport channels to the Transport format combination indicator(TFCI).

It is not necessary to transmit the TFCI for fixed data rates.

 Organize & Pack data from different services from the higher layers for suitable transportation

 Unpack incoming data and sort for delivery to upper layers

 Offers flexible data speeds and channel encoding  Efficient usage of radio resources

Transport Channels

Trang 37

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

37 (81)

Trang 38

Trang 39

Prep: Vikash Gupta

Checked:

Rev: PA1 Date: 2016-08-30

39 (81)

DCH (Dedicated Channel) Bi-directional channel for transporting both “dedicated ” user and control data; carries DTCH & DCCH.DCH is

characterized by fast data rate change on a frame by frame basis

BCH (Broadcast Channel) Downlink; Transports BCCH to UE; Always transmitted using the same transport format in entire cell

FACH (Forward Access Channel) Downlink; Transports small amount of data from BCCH/CCCH/DCCH/CTCH to either a specific UE or over the

entire cell

PCH (Paging Channel) Downlink; Transports data from PCCH to UE over entire cell

RACH (Random Access Channel) Uplink; Used by UE for initial access to UTRAN

CPCH (Common Packet Channel) Uplink; Used by UE to send packet data to UTRAN

DSCH (Downlink Shared Channel) With DSCH, user may be allocated different data rates,For example:

384kbps with SF 8and 192kbps with SF16.DSCH may be mapped to a multicode case,Ex-3channelisation codes with spreading factor 4 provide a DSCH with 2 MBPS.

Dedicated Transport Channel

Common Transport Channel

Trang 40

Mapping Logical To Transport Channels

Định dạng
Số trang	81
Dung lượng	2,06 MB