Alcatel UMTS Introduction
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UMTS/UTRAN Introduction
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 1
Introduction to UMTS
Table of contents 1.
Introduction
2.
Services Provided
3.
UMTS system description
4.
WCDMA for UMTS
5.
UTRAN (Release 1999)
Appendix Related Documentation Abbreviations and acronyms © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1. Introduction
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction
Definition
Universal Mobile Telecommunication System “UMTS is one of the major new third generation mobile communications systems being developed within the framework which has been defined by the ITU and known as IMT-2000” UMTS Forum © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 4
1. Introduction
1.1
Context
1.2
Standardization
1.3
UMTS goals
1.4
UMTS technical overview
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.1 Context
Past mobile systems (1) First Generation (1G) In the early 80‟s, analog systems e.g Radiocom 2000, C-Netz… Service: speech Limitations of 1G: •poor spectrum efficiency •expensive and heavy user equipment •mobility only in a small area •no security of communications
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.1 Context
Past mobile systems (2) Second Generation (2G) In the early 90‟s, digital systems Europe : GSM US : IS-95 (also called cdmaOne), IS-136 (TDMA system) Japan : PDC Services: Speech and low data rate Limitations of 2G: • Congestion more than 300 million wireless subscribers worldwide -->need to increase system capacity • Limited mobility around the world -->need for a global standardisation • Limited offer of services more than 200 million internet users--> Need for new multimedia services and applications (video telephony, e-commerce...)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.1 Context
Technical solutions
Two types of solutions were possible : • enhancement of 2G system --> 2,5G low cost but short term e.g.: HSCSD, GPRS, EDGE for GSM evolution • design of a complete new standard --> 3G high cost, long term, but great amount of new potential services e.g: UMTS
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.1 Context
GSM evolution (1) HSCSD (High Speed Circuit Switched Data) Principle: to enhance channel coding scheme and to bundle GSM time slots on a circuit-switched basis. Performance: up to 115,2 kbps Already implemented but not all operators/manufacturers have made this choice. GPRS (General Packet Radio Service)
Principle: to enhance channel coding scheme and to bundle GSM time slots on a packet-switched basis (the allocation of time slots is performed dynamically at the initialisation and during the connection) Performance: up to 171,2 kbps
1999/2000 : deployment phase 2002 : service offers for most operators © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.1 Context
GSM evolution (2) EDGE (Enhancement Data rates for GSM evolution) Principle: new modulation scheme (8PSK instead of GMSK) Performance: up to 384 kbps Implementation is yet to come (foreseen for 2003) EDGE might be a good alternative to 3G systems in certain areas or for operators who do not have 3G licences, although the 3G brings more in terms of new multimedia services.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.1 Context
Let’s take some examples! Downloading a map (50 KBytes) GSM 42 s GPRS 8 s EDGE 3 s UMTS 0.2 s
A 2 1/2 minutes MP3 music file (2.4 MBytes) GSM GPRS EDGE UMTS
34 mn 7 mn 128 s 10 s
Downloading a Word document Audio and Video (500 KBytes) streaming GSM 7 mn GPRS 82 s EDGE 27 s UMTS 2s © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Streaming with all technologies except with GSM
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1.Introduction
1.1
Context
1.2
Standardization
1.3
UMTS Goals
1.4
UMTS technical overview
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.2 Standardization
IMT-2000: definition
IMT-2000 is a framework for third generation mobile systems (3G) which is scheduled to start service worldwide around the year 2000 subject to market considerations.
IMT-2000 should use the frequencies around 2 GHz all over the world. IMT-2000 is defined by a set of interdependent ITU Recommendations*. IMT-2000 main requirements are : - wide range of high quality services - capability for multimedia applications - worldwide roaming capability - compatibility of services within IMT-2000 and with the fixed networks
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.2 Standardization
IMT-2000: main participants
Europe: ETSI Japan: ARIB USA: TIA, T1 South Korea: TTA China: CWTS
ITU: International Telecommunication Union
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.2 Standardization
IMT-2000: terrestrial radio interfaces IMT-TC (Time Code) TD-CDMA UMTS TDD
IMT-MC (Multi Carrier) CDMA2000 FDD MC
IMT-SC (Single Carrier) TDMA Single Carrier UWC-136 EDGE/ERAN IMT-FT (Frequency Time) TDMA Multi-Carrier DECT
IMT-DS (Direct Spread) W-CDMA UMTS FDD
Radio/Network Connection
Evolved GSM Core Network
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Evolved IS-41 Core Network
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1.Introduction/1.2 Standardization
2G terrestrial radio interfaces China :
GSM (87%)
US & Canada :
(13%)
GSM
GSM (12%)
CDMA
Western Europe:
(100%)
CDMA (49%)
TDMA
Japan:
(39%)
PDC (64%)
CDMA (36%)
Rest of the World :
GSM (41%)
CDMA (35%)
TDMA (24%)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
1999 Market Share: GSM 48 % CDMA 28 % TDMA 15 % PDC 9% Page 16
1.Introduction/1.2 Standardization
3G terrestrial radio interfaces China :
GSM (87%)
US & Canada :
GSM (12%) EDG E
UMTS
Western Europe:
GSM CDMA (49%) CDM A 2000
(100%)
UMTS TDMA (39%) EDG E
CDMA (13%) CDM A 2000 Japan:
PDC (64%)
UMTS Rest of the World :
GSM (41%)
UMTS
CDMA (35%) CDM A 2000 UMTS
TDMA (24%) EDG E
IMT2000
CDMA (36%) CDM A 2000 UMTS
1999 Market Share: GSM 48 % UMTS CDMA 28 % CDM EDG TDMA 15A% 9% EPDC
2000
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.2 Standardization
3GPP: joint organization for UMTS standardization Affiliated organizations: ETSI (Europe) ARIB/TTC (Japan) T1 (USA) TTA (South Korea) CWTS (China) Other members involved: manufacturers and operators System Specification: Access Network WCDMA (UTRA FDD) TD-CDMA (UTRA TDD) Core Network Evolved GSM All-IP Releases defined for the system specifications: - Release 99 (called R3 as well) - Release R4 and R5 (previously known as Release 2000 or R‟00)
In the following material we will only speak about UMTS R99. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.2 Standardization
3GPP organization
TSG Core Network
TSG Radio Access Network
WG1 Mobility Management, Call Control, Session Management
WG1 Radio layer 1 specifications
WG2 CAMEL & MAP
WG2 Radio layer 2, Radio layer 3 RR specification
TSG Service and System Architecture
WG1 Services
TSG GERAN GSM/EDGE*
TSG Terminals
WG1 Mobile Terminal Conformance Testing
SMG1 WG2 Architecture
WG2 Mobile terminal services & capabilities
SMG12 WG3 Interworking with External Networks
WG3 Iux specifications, UTRAN & O&M requirements
WG3 Security
WG3 USIM
SMG2 ARC WG4 MAP/GTP /BCH/SS
WG4 Radio performance/protocols, Base Station conformance
WG4 CODEC
WG5 OSA
Ad Hoc ITU internal coordination
WG5 Telecom Management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
* created in mid 2000
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1.Introduction/1.2 Standardization
3GPP specifications Series_Id 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35.
Series_description Requirements Service Aspects Technical Realization Signaling Protocols (UE to network) UTRA aspects CODECs Data (reserved) Signaling Protocols (intra-fixed network) Program management User Identity Module O&M Security Aspects Test specification Security algorithms
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.2 Standardization
UMTS Roadmap EDGE Commercial introduction
UMTS R99 commercial System
UMTS R99 Field Trials GPRS implementation
2000
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
2001
UMTS R4/R5
2002
2003
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1.Introduction
1.1
Context
1.2
Standardization
1.3
UMTS Goals
1.4
UMTS technical overview
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.3 UMTS goals
Why UMTS?
“UMTS will be a mobile communication system that offers significant user benefits including high-quality wireless multimedia services to a convergent network of fixed, cellular and satellite components.” It will deliver information directly to users and provide them with access to new and innovative services and applications. It will offer mobile personalized communications to the mass market regardless of location, network and terminal used.” UMTS Forum 1997
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.3 UMTS goals
UMTS vision
Zone 4: Global Satellite Zone 3: Suburban
Zone 2: Urban Zone 1: In-Building
Macro-Cell
MSS
GSM
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Micro-Cell
UTRA/ FDD
Pico-Cell
UTRA/ TDD
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1.Introduction
1.1
Context
1.2
Standardization
1.3
UMTS Goals
1.4
UMTS technical overview
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.4 UMTS technical overview
UMTS general architecture PS networks
CS networks
(Internet…)
(PSTN, ISDN..)
CN Iu
RAN Uu UE CN RAN UE
Core network (CN) it provides support for the network features and telecommunication services. It is connected to external CS networks or PS networks. Radio Access network (RAN) it comprises roughly the functions specific to the access technique. 3 different RANs are foreseen: •UTRAN (UMTS Terrestrial RAN) •MSS (Mobile Satellite component) •BRAN (Broadband RAN)
Core Network Radio Access Network User Equipment
User Equipment (UE) It is the mobile phone. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction/1.4 UMTS technical overview
UMTS Cellular System UMTS consists of a set of hierarchical cells, but the multiple access technique is completely different from GSM. GSM Users are separated in frequency (FDMA) and in time (TDMA)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
UMTS Users are separated with codes (CDMA)
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1.Introduction/1.4 UMTS technical overview
UMTS duplex modes 5 MHz channel
FDD mode
f1
Uplink
Code and Frequency orthogonality
f2
Downlink
5 MHz channel
TDD mode Code and Time orthogonality
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
...
Uplink & Downlink
...
15TS
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1.Introduction/1.4 UMTS technical overview
UMTS Frequency allocations
2110
2170
FDD 1900
1920
TDD
MSS 1980
FDD
2200
2010
MSS
2025
TDD Uplink
Downlink
FDD: Frequency Division Duplex TDD: Time Division Duplex MSS: Mobile Satellite System
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction
QUIZ! (1) Mark the following answers to the questions A to E by True or False. A. What are the limits of 2G systems like GSM? 1/ No security of communications 2/ No dynamical allocation of radio resources 3/ Mobility only in a small area 4/ Heavy mobile phones 5/ Limited offer of data services B. EDGE...
1/ is an evolution of GSM 2/ is sometimes considered as a 3G system 3/ is based on a new modulation scheme 4/ is supposed to reach a bit rate about 40 times greater than the GSM one
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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1.Introduction
QUIZ! (2) C. Which of these radio interfaces belongs to IMT-2000? 1/ CDMA One
2/ UMTS FDD
3/ UMTS TDD
4/ CDMA 2000
5/ EDGE
D. What is the organisation responsible for UMTS standardization? 1/ 3GPP
2/ 3GPP2
3/ ETSI
4/ ARIB
5/ CWTS
E. What is the bandwidth of a CDMA carrier in UMTS? 1/
200 kHz
2/
1 MHz
3/
5 MHz
F. Are the following statements about UTMS duplex modes True or False? 1/ FDD is similar to the GSM duplex mode 2/ TDD use the same frequencies as FDD 3/ FDD is better suited for asymmetric traffic 4/ TDD will come later © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided
2.1
UMTS service principles
2.2
UMTS Bearer services
2.3
Tele-services
2.4
UMTS Terminals
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.1 UMTS service principles
What is a service?
CN Node
UTRAN
TE/MT
E.g speech, file transfer, emails...
CN Gateway
Teleservice External Bearer Service
UMTS Bearer Service
E.g data transfer at 9,6 kbps, in transparent mode, with turbocode ...
TE
Radio Access Bearer Service (RAB) Radio Bearer Service ...
Iu Bearer Service
CN Bearer Service Backbone Bearer Service
...
Physical Radio Physical Bearer Service Bearer Service Uu
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Iu Page 34
2. Services provided/2.1 UMTS service principles
Tele-services and Bearer services Teleservices Speech, emergency calls SMS Email Internet Access Mobile e-commerce Video Postcards Information and location based services New applications
“Instinctive” service
Basic services
Enhanced services
New services to be provided by service providers (third party)
UMTS Bearer services Large toolkit for all kinds of services © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.1 UMTS service principles
Third party: service provider Tele-services will not be standardised so as to differentiate between operators and providers of applications. UMTS offer new opportunity for content and service providers Today‟s 1:1 customer-operator relationship Tomorrow‟s situation?
Contracted Content providers
Operator
Contracted Service providers
Contracted Service providers
Operator © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.1 UMTS service principles
Virtual Home Environment (VHE)
The Virtual Home Environment (VHE) is a portability concept of the PSE (Personal Service Environment): • VHE enables the users to carry along its PSE whilst roaming between networks • VHE shall be independent of terminal used (in fact the service configuration is adapted to the terminal capacities) • "same look and feel" wherever you are
PSE : the user has access to a range of services in its Home Environment.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.1 UMTS service principles
Service Architecture Service Layer
Tele-services (terminal equipment functions, Operator transmission capabilities)
Standardized interfaces Service Capability Features
Service Capability Servers
Bearer Services
GSM/GPRS/UMTS
CAMEL
MExE
SAT
Network Layer
Fixed
VHE concept is based on the standard mechanisms of Service Capability Servers which allow Service Capability Features. The latter are carried through standard interfaces in order to support Tele-services adapted to the Service Capabilities of the network and user equipment. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.1 UMTS service principles
Let’s Look for the nearest restaurant
Choose your preferences: - type of restaurant: French - type of payment: credit card ... Restaurant Paul Bocuse 69660 Collonges-au-Mont-d'or
This service is built from the following service capability features: call set-up & authorisation (CAMEL for services in roaming after authentication phase with SAT), Map display on the phone : SAT and MExE Call the restaurant by Push Service : MExE Reservation with VISA card number : secured transaction with MExE Billing of the service : CAMEL © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided
2.1
UMTS service principles
2.2
UMTS Bearer services
2.3
Tele-services
2.4
UMTS Terminals
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.2 UMTS Bearer Services
Bearer services characterization Bearer services are characterized by a set of end-to-end characteristics with requirements on QoS, always considered point-to-point. Bearer services provide the capability for information transfer between access points and involve only low layer functions. Each bearer service is characterized by its requirements: • transfer information: connection oriented or connectionless, traffic type (guaranteed/constant bit rate, non guaranteed/variable…), traffic characteristics (uni-directional, bi-directional, multicast…), priority • quality characteristics: maximum transfer delay, delay variation, bit error ratio, data rate. This set of requirements are called QoS parameters.
Example : several active radio bearer services can be handled simultaneously by the same terminal equipment. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.2 UMTS Bearer Services
Bearer QoS requirements • negotiable: QoS offer on demand • provide a wide range of QoS levels • dynamic behaviour: It shall be possible to negotiate (re-negotiate) the characteristics of a bearer service at session or connection establishment (during an on going session or connection).
• support of asymmetric nature between uplink and downlink • supply of bearer services without wasting resources on the radio and network interfaces.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.2 UMTS Bearer Services
Bearer Supported bit rates
The only limiting factor for satisfying application requirements shall be the cumulative bit rate per mobile termination at a given instant in each radio environment: At least 144 kbits/s in rural outdoor radio environment (with a maximum speed of 500 km/h) At least 384 kbits/s in urban or suburban outdoor radio environments (with a maximum speed of 120 km/h) •At least 2048 kbits/s in indoor or low range outdoor radio environment (with a maximum speed of 10 km/h) Theses performances decrease: - when the speed of the user increases - when the load of the network increases © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided
2.1
UMTS service principles
2.2
UMTS Bearer services
2.3
Tele-services
2.4
UMTS Terminals
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.3 Tele-services
Typology Media
Always-on
Fun • • • • •
Directories Mobile Office • • • • • •
Voice (!) E-mail Agenda IntraNet/InterNet Corporate Applications Database Access
• Yellow/White Pages • International Directories • Operator Services
Games (Hangman, Poker, Quiz, …) Screen Saver Ring Tone Horoscope Biorhythm
Music • Downloading of music files or video clips
Transportation • Flight/train Schedule • reservation
News (general/specific)
Vertical application • • • •
Traffic Management Automation Mobile branches Health
• • • • • • • •
International/National News Local News Sport News Weather Lottery Results Finance News Stock Quotes Exchange Rates
Location services • Traffic Conditions • Itineraries • Nearest Restaurant, Cinema, Chemist, Parking;, ATM ...
M-commerce Non physical • • • • • • © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
on-line Banking Ticketing Auction Gambling Best Price e-Book
Physical • on-line shopping • on-line food
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2. Services provided/2.3 Tele-services
QoS classes 4 classes have been identified: conversational AMR speech service Video telephony – CS: H324 – PS: H323
+ Delay sensitive
streaming interactive Web-browsing location based services
-
background
Data Integrity sensitive
+
e-mail delivery SMS ...
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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2. Services provided/2.3 Tele-services
Performance QoS of teleservices depends not only on UMTS network, but also on applications, terminals and external networks. From a user‟s perspective it is more relevant to speak of delay rather than bit rate:
Error tolerant
Conversational Streaming audio Voice messaging and video voice and video
FTP, still image, E-commerce, Error Telnet, WWW browsing paging intolerant interactive games
Conversational delay Intra-cell interference > User orthogonality is achieved by codes © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.3 Code Division Multiple Access
Multiple access (1)
Spreading 1
Transmitter 1
Spreading 2
Spreading1
Radio Channel
Receiver The receiver aims at receiving Transmitter 1 only.
Transmitter 2
All the users transmit on the same 5 MHz carrier at the same time and interfere with each over. At the receiver the users can be separated by means of (quasi-)orthogonal codes. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.3 Code Division Multiple Access
Multiple access (2)
Spreading 1
Transmitter 1
Spreading 2
Spreading1
Radio Channel
Receiver The receiver aims at receiving Transmitter 1 only.
Transmitter 2
If a user transmits with a very high power, it will be impossible for the receiver to decode the wanted signal (despite use of quasi-orthogonal codes) CDMA is unstable by nature and requires accurate power control. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.3 Code Division Multiple Access
Spreading: Channelization and scrambling
cch1 air interface
cch 2
cscrambling
Modulator
cch 3 The channelization code (or spreading code) is signal-specific: the code length is chosen according to the bit rate of the signal. The scrambling code is equipment-specific. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.3 Code Division Multiple Access
Channelization codes (spreading codes) C
C
ch,1,0
ch,2,0
C
ch,4,0
=(1,1,1,1)
C
ch,4,1
= (1,1,-1,-1)
C
ch,4,2
= (1,-1,1,-1)
C
ch,4,3
= (1,-1,-1,1)
= (1,1)
The code tree is shared by several users (usually one code tree per cell)
= (1)
C
SF = 1
ch,2,1
= (1,-1)
SF = 2
SF = 4
SF = 8
The channelization codes are OVSF (Orthogonal Variable Spreading Factor) codes: • their length is equal to the spreading factor of the signal: they can match variable bit rates on a frame-by-frame basis. • orthogonality enables to separate physical channels: Uplink: separation of physical channels from the same terminal Downlink: separation of physical channels to different users within one cell © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.3 Code Division Multiple Access
Scrambling codes The scrambling codes provide separation between equipment: • Uplink: separation of terminals No need for code planning (millions of codes!) There are 214 long and 214 short scrambling codes in uplink • Downlink: separation of cells Need for code planning between cells (but trivial task) There are only long scrambling codes in downlink (512 to limit the code identification during cell search procedure)
The long scrambling codes are truncated to the 10 ms frame length. Only one downlink scrambling code should be used within a cell. Another scrambling code may be introduced in one cell if necessary (example : shortage of channelization code), but orthogonality between users will be degraded. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS
4.1
Context
4.2
Spread Spectrum modulation
4.3
Code Division Multiple Access
4.4
Rake Receiver
4.5
Power Control
4.6
Soft Handover
4.7
Typical coverage and capacity values
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.4 Rake Receiver
Rake Receiver principle (1)
In a CDMA system there is a single carrier which contains all user signals. Decoding of all these signals by one receiver is only a question of signal processing capacity. A Rake receiver is capable to decode several signals simultaneously in the so called “fingers” and to combine them in order to improve the quality of the signal or to get several services at the same time.
A Rake receiver is implemented in mobile phones and in base stations. A Rake receiver can provide: - multi-service (via handling of multiple physical channels that are carrying the services) - soft handover - path diversity © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.4 Rake Receiver
Rake receiver principle (2) Delay Adjustment
Multi-code signal
1st Finger
Data 1
Delay 1 Code Sequence 1
2nd Finger
3rd Finger
Delay 2
Code Sequence 2
Data 2 Delay 3
Code Sequence 2 or 3
The components of the multi-code signal are demodulated in parallel each in one “finger” of the Rake Receiver. The outputs of the fingers: • can provide independent data signals • can be combined to provide a better data signal(s) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.4 Rake Receiver
Rake receiver and multi-service Despreading 1
Spreading 1
Spreading 2
Radio Channel Despreading 2
Transmitter
Multimedia receiver
As a first approach, we can say: One service, one code! (*) >> Which codes make it possible to separate the two signals at the receiver? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.4 Rake Receiver
Rake Receiver and soft handover Spreading 1
Base station 1
Spreading 2
Base Station 2
Despreading 1&2
Radio Channel
Mobile phone
>> Which codes make it possible to separate the two signals at the receiver?
Soft handover is possible, because the two mobile stations use the same frequency band. The mobile phone need only one transmission chain to decode both simultaneously. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.4 Rake Receiver
Rake Receiver and path diversity (1) Natural obstacles (buildings, hills…) cause reflections, diffractions and scattering and consequently multipath propagation. The delay dispersion depends on the environment and is typically: • 1 µs (300 m) in urban areas • 20 µs (6000 m) in hilly areas The delay dispersion should be compared with the chip duration 0,26 µs (78 m) of the CDMA system. If the delay dispersion is greater than the chip duration, the multipath components of the signal can be separated by a Rake Receiver.
In this case, CDMA can take advantage of multipath propagation.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.4 Rake Receiver
Rake Receiver and path diversity (2) Direct path Despreading
Spreading
Transmitter
Reflected path
Receiver
Dispersion > Which codes make it possible to separate the two signals at the receiver?
Direct path Spreading
Transmitter
Despreading
Reflected path
Receiver
Dispersion > Chip duration The Rake Receiver can provide path diversity to improve the quality of the signal. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 99
4. WCDMA for UMTS
4.1
Context
4.2
Spread Spectrum modulation
4.3
Code Division Multiple Access
4.4
Rake Receiver
4.5
Power Control
4.6
Soft Handover
4.7
Typical coverage and capacity values
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 100
4. WCDMA for UMTS/ 4.5 Power Control
Why Power Control?
MS2
MS1 Node B
Near-Far Problem on the uplink way an overpowered mobile phone near the base station can jam any other mobile phones far from the base station. > Need for very efficient and very fast Power Control on UL > Power Control is also used in DL to reduce interference and consequently to increase the system capacity. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.5 Power Control
Open Loop Open loop power control
1 Node B
1 Node B
2
If UE receives a STRONG DL signal, then UE will speak low.
2
If UE receives a weak DL signal, then UE will speak LOUD.
Problem: fading is not correlated on UL and DL due to separation of UL and DL band. Open loop Power Control is inaccurate.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.5 Power Control
Closed Loop Closed loop power control
”Power down” SIR estimation
RNC
SIR target
Node B
SIR estimation
”Power down” ”Power up”
SIR estimation
”Power ...”
SIR estimation
...
The Node-B controls the power of the UE (and vice versa) by performing a SIR estimation (inner loop). The RNC controls parameters of the SIR estimation (outer loop). This SIR estimation is performed each 0,66 ms (1500 Hz command rate). Closed loop Power Control is very fast. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS
4.1
Context
4.2
Spread Spectrum modulation
4.3
Code Division Multiple Access
4.4
Rake Receiver
4.5
Power Control
4.6
Soft Handover
4.7
Typical coverage and capacity values
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.6 Soft Handover
Soft Handover (1)
RNC
Node B Node B
Node B
Soft HO © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Softer HO Page 105
4. WCDMA for UMTS/ 4.6 Soft Handover
Soft Handover (2) Why do we need soft HO? Imagine that a UE penetrates from one cell deeply into an adjacent cell: > it may cause near-far problem > hard HO is not a good solution, because of the need for the hysteresis mechanism Additional resources due to soft HO: - Additional rake receiver in Node-B - Additional Rake Fingers in UE - Additional transmission links between Node-Bs and RNCs Soft HO provides Diversity (also called Macro-Diversity), but requires more network resource.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.6 Soft Handover
Soft Handover (3) Soft Handover execution: Soft Handover is executed by means of the following procedures Radio Link Addition (FDD soft-add); Radio Link Removal (FDD soft-drop); Combined Radio Link Addition and Removal.
The cell to be added to the active set needs to have information forwarded by the RNC: Connection parameters (coding scheme, layer 2 information, …) UE ID and uplink scrambling code, Timing information from UE
The UE needs to get the following information Channelization & scrambling codes to be used Relative timing information (Timing offset based on CPICH synchro)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS
4.1
Context
4.2
Spread Spectrum modulation
4.3
Code Division Multiple Access
4.4
Rake Receiver
4.5
Power Control
4.6
Soft Handover
4.7
Typical coverage and capacity values
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.7 Typical coverage and capacity values
Radio dimensioning process: What’s new?
Market perspective Mobile data market forecast Marketing inputs Multi-service environment Voice+data Variable bit rate Different QoS Asymmetric traffic New radio technology W-CDMA
Coverage
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Capacity
Quality
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4. WCDMA for UMTS/ 4.7 Typical coverage and capacity values
Concentric coverage
The coverage is determined by the uplink range, because the transmission power of the terminal is much lower than that of the base station.
UE Transmit Power 21 dBm (126 mW)
24 dBm (251 mW)
Service in suburban area Cell radius (uplink limited)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Speech 12 kbit/s 3 km
Packet data 144 kbit/s
Packet data 384 kbit/s
2 km
1,5 km
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4. WCDMA for UMTS/ 4.7 Typical coverage and capacity values
Ways of improving coverage AMR speech Codec it enables to switch to a lower bit rate if the mobile is moving out of the cell coverage area: it is a trade-off between quality and coverage. Multipath diversity it consists of combining the different paths of a signal (due to reflections, diffractions or scattering) by using a Rake Receiver. Multipath diversity is very efficient with W-CDMA. Soft(er) handover the transmission from the mobile is received by two or more base stations. Receive antenna diversity the base station collects the signal on two uncorrelated branches. It can be obtained by space or polarization diversity. Base stations algorithms e.g. accuracy of SIR estimation in power control process © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.7 Typical coverage and capacity values
Soft capacity The capacity is determined by the downlink direction, because: - better receiver techniques can be used in the base station than in the mobile station (but requiring more CPU power). - the downlink capacity is expected to be more important than the uplink capacity because of asymmetric traffic. The downlink capacity has two limitations: - the amount of interference in the air interface Adjacent cells share part of the same interference: there is an additional capacity in a cell, if the number of users in the neighboring cells is smaller. - the loss of code orthogonality The downlink codes originate from a single point and can be synchronized. But, after transmission over multipath channel, part of orthogonality is lost. It is a soft capacity, because it is not limited by the hardware equipment. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS/ 4.7 Typical coverage and capacity values
Parameters influencing capacity The capacity depends on: - the radio environment (rural, suburban, indoor) - the terminal speeds - the distribution of the terminals - the load of the cell: trade-off capacity/coverage (breathing cells)
High loaded cell High DL interference level DL data throughput 660 kbps (per carrier per sector)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
High loaded cell Low DL interference level DL data throughput 1440 kbps (per carrier per sector)
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4. WCDMA for UMTS
QUIZ! A. True or False? Spreading...
1/ consists of increasing the power while decreasing the frequency bandwidth 2/ allows to transmit a signal with a S/N (Signal-to-Noise ratio) smaller than one 3/ enables to retrieve the coded signal at the receiver by using the same code in phase 4/ is used in FDMA system
B. Signal 1 has a bit rate of 12 kbps and a coding rate of 1/3, signal 2 has a bit rate of 384 kbps and a coding rate of 1/2: 1/ Which spreading factor should be chosen for each of these signals? 2/ What is the processing gain for each of these signals?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS
QUIZ! C. True of false? WCDMA... 1/ is also called UMTS FDD or UTRA FDD 2/ uses a 1 MHz bandwidth carrier 3/ has a chip rate of 3,84 Mchips/s D. How many carriers are there per operator for WCDMA? 1/ 124 carriers
2/ 62 carriers
3/ 1 to 3 according to the country
E. True or false? A Rake Receiver 1/ can separate simultaneously two signals only if their codes are perfectly orthogonal 2/ can separate simultaneously several signals of 2 different WCDMA carriers 3/ can take advantage of multipath propagation
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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4. WCDMA for UMTS
QUIZ! F. True or false? In WCDMA, power control 1/ is used in uplink and in downlink 2/ is crucial in downlink because of near-far problem
3/ is composed of the open loop and the closed loop 4/ may be performed each WCDMA time slot (1500 Hz command rate)
G. True or false? Soft handover... 1/ is highly desirable in WCDMA 2/ require use of more frequencies 3/ require use of more power in uplink 4/ require additional signal processing equipment such as Rake Receiver 5/ require additional transmission links © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UMTS Terrestrial Radio Access Network (FDD mode, Release 1999)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN
UTRAN role and principles Layer 3 Layer 2
Layer 1
Uu UE
Iub Node B
RNC
CN
• To transfer traffic and control channels between UE and CN - Common handling of packet-switched and circuit-switched data - Protection of the user data on the air interface (providing of ciphering) - Independence from the applied transport technology on the Iu interface • To manage the radio mobility of the user Full control of UE radio mobility with the use of the Iur interface which makes it possible to perform soft HO even with 2 cells/Node-Bs belonging to different RNCs. • To make efficient use of limited radio resources Support of WCDMA specific Radio Resource Management (RRM) algorithms. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 118
5. UTRAN
Layer 3 Layer 2 Layer 1 UE
5.1
From Radio Bearers to transport channels
5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signalling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource Management (RRM)
5.8
Mobility management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Node B
RNC
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5. UTRAN/5.1 From Radio Bearers to transport channels
Situation CN Node
UTRAN
UE
CN Gateway
UE
Teleservice External Bearer Service
UMTS Bearer Service Radio Access Bearer Service (RAB) Radio Bearer Service
... Radio Physical Bearer Service Uu © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Iu Bearer Service
CN Bearer Service Backbone Bearer Service
... Physical Bearer Service
Iu Page 120
5. UTRAN/5.1 From Radio Bearers to transport channels
Radio Bearers, logical and transport channels Control plane
User plane
Web browsing
NAS signalling
Telephony speech
RRC Signalling Radio Bearers
RRC connection establishment
SMS Cell Broadcast
PDCP
User plane Radio BMCBearers
RLC Control Logical Channel s
Traffic Logical Channels
... MAC
MAC Transport Channels
Transport Channels (Iur)/Iub/Uu
Phys. UTRAN © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Phys.
UE Page 121
5. UTRAN/5.1 From Radio Bearers to transport channels
Radio Bearers Signalling Radio Bearers (SRB) SRBs can carry: - layer 3 signalling (e.g. RRC connection establishment) - NAS signalling (e.g location update)
There can be up to 4 SRBs per RRC connection (one UE has one RRC connection when connected to the UTRAN). User Plane Radio Bearers
RABs are mapped on user plane RBs. One RAB can be divided on RAB sub-flows and each sub-flow is mapped on one user plane RB. e.g the AMR codec encodes/decodes speech into/from three sub-flows; each sub-flow can have its own channel coding. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Logical Channels (1)
Control Channels (CCH) Broadcast Control Channel (BCCH) Paging Control Channel (PCCH)
UTRAN
Common Control Channel (CCCH) Dedicated Control Channel (DCCH)
Traffic Channels (TCH) Dedicated Traffic Channel (DTCH) Common Traffic Channel (CTCH)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels Logical
UL ( ) / DL ( )
Channels (2)
Wha t type of informa tion?
BCCH
System control information e.g cell identity, uplink interference level
PCCH
Paging information e.g CN originated call when the network does not know the location cell of the UE
CCCH
Control information e.g initial access (RRC connection request), cell update
DCCH
Control information (but the UE must have a RRC connection) e.g radio bearer setup, measurement reports, HO
DTCH
Traffic information dedicated to one UE e.g speech, fax, web browsing
CTCH
Traffic information to all or a group of UEs e.g SMS-Cell Broadcast
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels Why
Transport Channels?
A transport channel offers a flexible pattern to arrange information on any service-specific rate, delay or coding before mapping it on a physical channel: • it provides flexibility in traffic variation • it enables multiplexing of transport channels on the same physical channel
Transport channels provide an efficient and fast flexibility in radio resource management.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Structure of a Transport Channel (1) Transport Block: basic unit exchanged over transport channels.
Transport Format (TF): it may be changed every TTI. Each TF must belong to the Transport Format Set (TFS) of the transport channel
168 360 bits
168
168
168
360
168
168
168
10 ms
10 ms
Time Transmission Interval (TTI): periodicity at which a Transport Block Set is transferred by the physical layer on the radio interface © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
10 ms
10 ms
>> The system delivers one Transport Block Set to the physical layer every TTI: what is the delivery bit rate of the transport blocks to the physical layer during the first TTI?
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5. UTRAN/5.1 From Radio Bearers to transport channels
Structure of a Transport Channel (2) Transport Format (TF) • Semi-static part (can be changed, but long process) Transmission Time Interval (TTI), Coding scheme...
• Dynamic part (may be changed easily) Size of transport block, Number of transport blocks per TTI Transport Format Set (TFS) It is the set of allowed Transport Formats for a transport channel, which is assigned by RRC protocol entity to MAC protocol entity. MAC chooses TF among TFS. MAC may choose another TF every TTI without interchanging with RRC protocol (fast radio resource control). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Example 576 bits
576
576 576
576
576
576
576
576
40 ms Sta tic Pa rt TTI Coding scheme CRC
? Turbo coding, coding rate= 1/ 3 16 bits
Dyna mic Pa rt Transport Block Size Transport Block Size Set
? 576*B (B= 0,1,2,3,4)
1. Complete the table 2. What is the delivery bit rate of the transport blocks to the physical layer during the first TTI?
3. How many Transport Format(s) may be chosen for this transport channel?
4. Can you imagine why the transfer has been interrupted during the third TTI? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Transport Channels
Common Channels Broadcast Channel (BCH) Paging Channel (PCH)
UTRAN
Forward Access Channel (FACH) Downlink Shared Channel (DSCH) Random Access Channel (RACH) Common Packet Channel (CPCH)
Dedicated Channels Dedicated Channel (DCH)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Common Transport Channels (1) BCH:
Broadcast Channel
A downlink transport channel that is used to carry BCCH. The BCH is always transmitted with high power over the entire cell with a low fixed bit rate. >> The BCH is the only transport channel with a single transport format (no flexibility). Can you explain why?
PCH:
Paging Channel
A downlink transport channel that is used to carry PCCH. It is always transmitted over the entire cell. >> Is it possible to carry all types of information on the PCH?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Common Transport Channels (2) FACH:
Forward Access Channel
A downlink transport channel that is used to carry control information. It may also carry short users packets. The FACH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas. The FACH uses open loop power control (slow power control). >> In which case is it interesting to use beam-forming antennas? would it also be relevant to implement this feature for PCH? RACH: Random Access Channel An uplink transport channel that is used to carry control information from the mobile especially at the initial access. It may also carry short user packets. The RACH is always received from the entire cell and is characterized by a limited size data field, a collision risk and by the use of open loop power control (slow power control). >> Why is it interesting to carry short user packets on RACH in spite of limited data field and collision risk (instead of using a dedicated channel)? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Common Transport Channels (3) DSCH: Downlink Shared Channel A downlink transport channel shared by several UEs to carry dedicated control or user information. When a UE is using the DSCH, it always has an associated DCH, which provides power control. CPCH: Common Packet Channel An uplink transport channel that is used to carry long user data packets and control packets. It is a contention based random access channel. It is always associated with a dedicated channel on the downlink, which provides power control.
Transfer of signalling and traffic on a shared basis
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Dedicated Transport Channels DCH:
Dedicated Channel
A downlink or uplink transport channel that is used to carry user or control information. It is characterized by features such as fast rate change (on a frame-by-frame basis), fast power control, use of beam-forming and support of soft HO.
>> Two features are only applied on DCH: can you guess which?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Mapping LogicalTransport Channels Control Logical Channels BCCH
BCH
PCCH
PCH
CCCH
RACH
Traffic Logical Channels
DCCH
FACH
DTCH
DSCH
Common Transport Channels
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
CPCH
CTCH
DCH Dedicated Transport Channels Page 134
5. UTRAN/5.1 From Radio Bearers to transport channels
Mapping Logical Transport Channels Control Logical Channels BCCH
BCH
PCCH
PCH
CCCH
RACH
Traffic Logical Channels
DCCH
FACH
DTCH
DSCH
Common Transport Channels
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
CPCH
CTCH
DCH Dedicated Transport Channels Page 135
5. UTRAN/5.1 From Radio Bearers to transport channels
Complete the gaps! (1) … channels are defined by what type of information (e.g user data, signalling, system information...) is transported over the radio interface. (2) … channels
are defined by how and with what characteristics (e.g type of coding, required transfer delay, required BER... ) data are transferred over the radio interface. (3) … channels are defined by the mechanisms (e.g frequency, code, power, framing...) with which the data are transferred over the physical resources of the airinterface. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.1 From Radio Bearers to transport channels
Complete the table! Traffic cla ss Signa lling 1. … 2. … 3. … 4. …
-
Logica l Channel
Transport Channel
BCCH PCCH CCCH DCCH
BCH, FACH PCH UL: RACH, DL: FACH RACH, DCH
UL: 3 coordinated DCHs DL: 3 coordinated DCHs UL: RACH, DL: FACH UL: CPCH, DCH DL: DSCH,DCH UL: CPCH, DCH DL: DSCH,DCH UL: CPCH, DCH DL: DSCH,DCH FACH
User information 5. …
Conversational
6. …
Interactive
3 DTCHs DTCH
7. …
Interactive
DTCH
8. …
Streaming
DTCH
9. …
Background
DTCH
10. …
Background
CTCH
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN
Layer 3 Layer 2 Layer 1 UE
5.1
From Radio Bearers to transport channels
5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signalling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource Management (RRM)
5.8
Mobility management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Node B
RNC
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5. UTRAN/5.2 Radio Protocols
Radio protocol stack Control plane
User plane
Non Access Stratum
Bearers (called RAB in user plane)
Access Stratum control
RRC control
control
Layer 3
SAP BMC
control
control
Layer 2/PDCP Layer 2/BMC
PDCP PDCP
Radio Bearers
Layer 2/RLC RLC
RLC RLC RLC RLC
RLC RLC RLC
Logical Channels Layer 2/MAC
MAC Transport Channels
Layer 1
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
PHY
Page 139
5. UTRAN/5.2 Radio Protocols
Radio Resource Control (RRC) Call management
Bearers
Radio mobility management RRC control
Radio Bearers (control plane)
Measurement control and reporting control
control control control
Layer 3
Outer loop power control PDCP BMC
RLC
MAC PHY
RRC is the brain of the radio interface protocol stack. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.2 Radio Protocols
PDCP and BMC protocols PDCP (Packet Data Convergence Protocol) - in the user plane, only for services from the PS domain - it contains compression methods
In R99 only a header compression method is mentioned (RFC2507). Why is header compression valuable? e.g a combined RTP/UDP/IP headers is at least 60 bytes for IPv6, when IP voice service header can be about 20 bytes or less. BMC (Broadcast/Multicast Services) - in the user plane - to adapt broadcast and multicast services from NAS on the radio interface
In R99 the only service using this protocol is SMS Cell Broadcast Service (directly taken from GSM). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.2 Radio Protocols
Radio Link Control (RLC)
Segmentation Radio Bearers (user plane)
Radio Bearers (control plane) Layer 2/ upper part
RLC
RLC RLC RLC
Control Logical Channels
RLC RLC RLCRLC Traffic Logical Channels
Buffering Data transfer with 3 configuration modes: - Transparent (TM) - Unacknowledged (UM) - Acknowledged (AM) Ciphering
RLC provides segmentation and (in AM mode) reliable data transfer. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.2 Radio Protocols
Medium Access Control (MAC) Traffic Logical Channels
Control Logical Channels Layer 2/ lower part
Basic data transfer Multiplexing of logical channels Priority handling/Scheduling (TFC selection)
MAC Transport Channels (common and dedicated)
Reporting of measurements Ciphering
MAC can switch a common channel into a dedicated channel if higher bit rate is required (on request of L3-level).
MAC can change dynamically Transport Format (bit rate…) of each transport channel on a frame basis (each 10 ms) without interchanging with L3-level. MAC provides flexible data transfer. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.2 Radio Protocols
TFC selection in MAC protocol Several transport channels can be time-coordinated to be multiplexed on a CCTrCH before mapping on one physical channel (or more if necessary).
MAC TFC selection
Transport Format (TF)
e.g.
DCH1 = {244} DCH2 = {0 ; 148} DCH3 = {0 ; 148}
Transport Format Set (TFS) Transport Format Combination (TFC)
DCH1 DCH2 DCH3
TrCH multiplexing
TFCS = { {244 ; 0 ; 0} , {244 ; 148 ; 0} , {244 ; 0 ; 148} } Transport Format Combination Set (TFCS)
MAC selects TFC inside TFCS. There is one TFCS per CCTrCH. >> Why is the combination {244 ; 148 ; 148} not possible? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
CCTrCH
Physical channel Mapping
L1 Physical Channel(s)
Page 144
5. UTRAN/5.2 Radio Protocols
The Physical Layer
Common Transport Channels
Dedicated Transport Channels
Multiplexing of transport ch. Spreading/modulation
Physical layer
Layer 1
RF processing Dedicated Physical Channels
Common Physical Channels
Power control
Measurements
Air Interface
The physical layer provides multiplexing and radio frequency processing with a CDMA method. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 145
5. UTRAN/5.2 Radio Protocols
Exercise: MAC protocol (1) BCCH
PCCH
BCCH
CCCH
CTCH
DCCH DTCH DTCH
MAC Control
MAC-d
MAC-b
BCH
MAC-c/sh
PCH FACH FACH RACH CPCH
DSCH DSCH
DCH DCH
Iur or local
Look at this figure and answer the questions on the following pages. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.2 Radio Protocols
Exercise: MAC protocol (2)
1. On which logical/transport channels will be mapped: - system information broadcasting - paging - telephony speech - internet browsing at a high bit rate - internet browsing at a low bit rate Can you imagine a situation where the UE will use 2 DTCHs (or more) at the same time?
2. Guess the meaning of “MAC-b” “MAC-c/sh” and “MAC-d”. 3. Why is there one MAC-d entity on the UE side and several MAC-d entities on the UTRAN side? 4. What is the link between MAC-c/sh and MAC-d for? 5. What are the 4 main functions of MAC protocol? 6. MAC can multiplex logical channels only if they require the same QoS: true or false?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.2 Radio Protocols
Exercise: MAC protocol (3)
7. RNTI (Radio Network Temporary Identity) is an UE identity assigned by UTRAN, when the UE is connected to the UTRAN . The parameter RNTI is included in the header of each transport blocks in MAC-c/sh, but not in MAC-d : can you explain the reason? 8. The system can also multiplex transport channels: where does that take place? 9. What is the name of the channel on which several time-coordinated transport channels can be multiplexed? 10. Which entity is responsible for TFC selection? TFCS allocation? 11. Is it possible to multiplex 2 FACHs (or more)? 2 DCHs (or more)? a FACH and a DCH? 12. Will the physical channel configuration be changed (e.g modification of spreading factor) when MAC selects a new TFC inside TFCS? 13. MAC makes measurement reports to RRC: why is it necessary?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN
Layer 3 Layer 2 Layer 1 UE
5.1
From Radio Bearers to transport channels
5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signaling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource Management (RRM)
5.8
Mobility management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Node B
RNC
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5. UTRAN/ 5.3 Iu protocols
General model The same general protocol model is applied for all Iu interfaces: Radio
Control Plane
User Plane
Network
Application Protocol
Data Stream(s)
Layer Transport
Transport Network User Plane
Transport Network User Plane
ALCAP
Network Layer
Transport Network Control Plane
Signaling Bearer(s)
Signaling Bearer(s) Physical Layer
Application Protocols:
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Data Bearer(s)
1. What is the purpose of the separation between the Radio Network Layer and the Transport Network Layer? 2. Why is ALCAP protocol necessary?
- NBAP for Iub interface - RNSAP for Iur interface - RANAP for Iu-CS and Iu-PS interfaces Page 150
5. UTRAN/ 5.3 Iu protocols
Iub protocols Radio Link Establishment
RABs*
RRC Connection Establishment* NAS signalling*
RNC Radio Network Layer Transport
Control Plane
User Plane
NBAP
Frame Protocols (IubFP)
Transport Network User Plane
Transport Network Control Plane
ALCAP
Network Layer
Transport Network User Plane
AAL5
AAL5
AAL2
ATM
Physical Layer * at this stage these data streams have been mapped on transport channels by MAC protocol © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Node B Page 151
5. UTRAN/ 5.3 Iu protocols
Iur protocols
SRNC
Establishment of an additional radio link to an UE (for soft HO) Radio Network Layer Transport
RABs*
RRC Connection Establishment* NAS signalling*
Control Plane
User Plane
RNSAP
Frame Protocols (Iur FP)
Transport Network User Plane
Network
...
Layer
AAL5
Transport Network Control Plane
Transport Network User Plane
ALCAP AAL5
AAL2
ATM Physical Layer * at this stage these data streams have been mapped on transport channels by MAC protocol © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
DRNC Page 152
5. UTRAN/ 5.3 Iu protocols
UTRAN protocols: general recap RRC PDCPBMC
RRC PDCPBMC
RLC MAC
RLC Uu
Iub
MAC
SRNC ... ... AAL5 AAL5 AAL2
NBAP ALCAP Iub-FP Iur-FP ALCAPRNSAP ... ... ... ... AAL5 AAL5 AAL2 AAL2 AAL5 AAL5
ATM/Physical layer
ATM/Physical layer
NBAP ALCAP Iub-FP
Soft(er) combining Softer combining
Phy. (air)
UE
Phy. (air)
Soft combining
Node-B
Iur
RRC PDCPBMC RLC
Radio Protocols
Iu Protocols (Radio Network Layer) Iu protocols (Transport Network Layer) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
DRNC
MAC
NBAP ALCAP Iub-FP Iur-FP ALCAPRNSAP ... ... ... ... AAL5 AAL5 AAL2 AAL2 AAL5 AAL5 ATM/Physical layer
Page 153
5. UTRAN
5.1
?
From Radio Bearers to transport channels
? 5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signalling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource Management (RRM)
5.8
Mobility management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.4 UE identifiers and UE states
UE identifiers
2 types of UE identification on the radio interface:
• NAS identifiers - IMSI: International Mobile Subscriber Identity - TMSI: Temporary Mobile Station Identity They are used in the initial access CCCH message • UTRAN identifier - RNTI: Radio Network Temporary Identity This is allocated by the UTRAN for each UE in connected mode and used for inband identification in common transport channels (e.g FACH). The RNTI is not used outside the UTRAN.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.4 UE identifiers and UE states
UE states (1) RRC Connection Release
out of coverage
UE
UE
UE
detached
in idle mode
in connected
mode
“just after switch on” process Including Cell search procedure
RRC Connection Establishment
Why is the idle mode necessary? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 156
5. UTRAN/5.4 UE identifiers and UE states
UE states (2) RRC Connection Release
out of coverage
RRC Connection Establishment procedure
UE UE
UE
in connected
detached
in idle mode
mode
“just after switch on” process
CCCH RNC
RRC Connection Establishment
1
- UE in idle mode, - a Common Control Channel (CCCH) is used to initiate the procedure
2
- Setup of a Dedicated Control Channel (DCCH)
3
- UE in connected mode - The DCCH is used during the whole time of the RRC connection to carry signalling dedicated to this particular UE
CCCH DCCH
DCCH
RNC
RNC
Which type of transport channel are used to carry CCCH? DCCH? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 157
5. UTRAN/5.4 UE identifiers and UE states
UE states (3) Cell_DCH state Signalling and traffic data dedicated to the UE (mapped on DCCH and DTCH respectively) are carried on DCH transport channel
UE in connected Cell DCH mode UE in idle mode
Cell PCH Cell FACH URA PCH
Cell_FACH state Signalling and traffic data dedicated to the UE (mapped on DCCH and DTCH respectively) are carried on RACH (uplink) and FACH (downlink) transport channels
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Cell_DCH Cell_FACH No traffic UL/DL at expiry of timer 1 Cell_FACH Cell_DCH Traffic volume UL/DL too large
Page 158
5. UTRAN/5.4 UE identifiers and UE states
UE states (4) Cell_PCH state No transmission of signalling and traffic data dedicated to the UE (no DCCH and no DTCH)
Cell DCH UE in idle
But the RRC connection is still active (UTRAN keeps RNTI for UE) and UE location at a cell level. - a DCCH (and possibly a DTCH) can be reestablished very quickly (this procedure is initiated by sending a paging signal PCH)
URA_PCH state Very similar to cell_PCH state UTRAN keeps the location of the UE at the URA level (set of UMTS cells) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
UE in connected mode
mode
Cell PCH Cell FACH URA PCH
Cell_FACH Cell_PCH No traffic UL/DL at expiry of timer 2 Cell_PCH Cell_FACH URA_PCH Too many cell reselections Cell/URA_PCH Cell_FACH Incoming DL or UL traffic Page 159
5. UTRAN/5.4 UE identifiers and UE states
UE identifiers and UE states: complete the table!
UE Sta tes idle mode
CN UTRAN UE Identifiers UE Loca tion UE Identifier UE Loca tion IMSI, TMSI
LA, RA
cell_DCH connected mode
cell_FACH cell_PCH URA_PCH
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 160
5. UTRAN
Layer 3 Layer 2 Layer 1 UE
5.1
From Radio Bearers to transport channels
5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signaling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource Management (RRM)
5.8
Mobility management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Node B
RNC
Page 161
5. UTRAN/5.5 Signaling procedures
List of basic signaling procedures A. Broadcast of system information B. Paging B1. Paging Type 1 (in idle mode or in cell_PCH or in URA_PCH states) B2. Paging Type 2 (in cell_FACH or cell_DCH states) C. RRC Connection C1. RRC Connection Establishment (to cell_FACH and to cell_DCH states) C2. RRC Connection Release (in cell_DCH states) D. Radio Link establishment
E. Direct Transfer F. Control of RAB, RB, Transport Channel and Physical Channel F1. RAB Establishment F2. Physical Channel Reconfiguration
G. Soft HO (Radio Link Addition) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 162
5. UTRAN/5.5 Signaling procedures
How to read call scenario diagrams Logical channel Name of the message
Transport channel
RNC
UE RRC
1. RRC Connection Request (CCCH:RACH) Initial UE identity, Establishment cause, Initial UE capability
RRC
Network entity
Protocol entity
Parameters of the message © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.5 Signaling procedures
A. System Information Broadcasting (1) The broadcast system information:
- may come from CN, RNC or Node-B. - contains static parameters (Cell identity, supported PLMN types...) and dynamic parameters (UL interference level...). - is arranged in System Information Blocks (SIB), which group together elements of the same nature. - can be carried on BCH which is transmitted permanently over the entire cell. >> Do you think the UE needs to read all the SIBs each time a broadcast is repeated?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.5 Signaling procedures
A. System Information Broadcasting (2) UE
RNC
Node-B NBAP
NBAP RRC
System Information (BCCH:BCH) Master/Segment Info Block(s) RRC
RRC
System Information (BCCH:BCH) Master/Segment Info Block(s) RRC
System Information (BCCH:BCH) RRC Master/Segment Info Block(s) RRC
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
CN
System Information Update Request NBAP Master/Segment Info Block(s), BCCH modification time System Information Update Response
NBAP
>> Why does RRC protocol terminate at Node-B for BCH (not at RNC)? Page 165
5. UTRAN/5.5 Signaling procedures
B. Paging Paging is typically used at core network-originated call. UE in idle mode The network will page the UE in LA (CS domain) or RA (PS domain)
UE is in connected mode The network will page the UE: - in the cell (in cell_PCH, cell_FACH, cell_DCH states) - in the URA (in URA_PCH state) Paging Type 1: mapped on PCCH/PCH Paging Type 2: mapped on DCCH/FACH or DCCH/DCH >> Can you guess which Paging Type will be use in idle mode? in cell_PCH state? in cell_FACH state? in cell_DCH state? in URA_PCH state? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.5 Signaling procedures
B1. Paging Type 1 UE 1
UE 2
Node-B 1
Node-B 2
RNC 1
RANAP
1. Paging CN Domain Indicator, UE identity, Paging cause
RANAP
RRC
2. Paging Type 1 (PCCH:PCH)
RRC
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
CN
RNC 2
1. Paging Idem
RANAP
RANAP
RRC
2. Paging Type1 (PCCH:PCH)
RRC
Page 167
5. UTRAN/5.5 Signaling procedures
B2. Paging Type 2 UE
Node-B
RANAP
RRC
2. Paging Type 2 (DCCH:FACH or DCH)
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
CN
SRNC
1. Paging CN Domain Indicator, UE identity, Paging cause
RANAP
RRC
Page 168
5. UTRAN/5.5 Signaling procedures
C. RRC connection RRC connection is established at the initial access (after cell search procedure when the UE is camping on a cell).
After RRC connection establishment: - UE will switch from idle mode to cell_FACH or cell_DCH states. - UE will have a signalling link with UTRAN (on DCCH)
UE needs to establish a RRC connection prior to making : - voice call - location update - measurement reporting ... © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.5 Signaling procedures
C1. RRC Connection Establishment UE RRC
RNC
Node-B 1. RRC Connection Request (CCCH:RACH) Initial UE identity, Establishment cause, Initial UE capability
RRC
2. Allocate RNTI, Select Level 1 and Level 2 parameters (e.g. TFCS, scrambling code) 3. Radio Link Establishment (see Procedure D)
RRC
RRC
4. RRC Connection Setup (CCCH:FACH) Initial UE identity, RNTI, capability update requirement, TFS, TFCS, frequency, UL scrambling code, power control info
5. RRC Connection Setup Complete (DCCH:RACH or DCH) Integrity information, ciphering information
RRC
RRC
>> Can the UE send user information (e.g voice call) after completing this stage? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 170
5. UTRAN/5.5 Signaling procedures
C2. RRC Connection Release (in cell_DCH state) UE
Node-B of DRNC
DRNC
Node-B of SRNC
CN SRNC 1. Iu Release Command RANAP RANAP Cause
2. Iu Release Complete RANAP RANAP -
3. ALCAP Iu Bearer Release RRC RRC
4. RRC Connection Release (DCCH:DCH ) Cause
5. RRC Connection Release Complete (DCCH:DCH ) -
RRC RRC
6. Radio Link Deletion 7. Radio Link Deletion 8. Radio Link Deletion © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 171
5. UTRAN/5.5 Signaling procedures
D. Radio Link (RL) Establishment for a DCH RNC
Node-B NBAP
Radio Link Setup Request Cell id, TFS, TFCS, frequency, UL scrambling code, power control info
NBAP
Start RX ALCAP Iub Data Transport Bearer Setup NBAP
Iub-FP Iub-FP
Radio Link Setup Response Signalling link termination, transport layer addressing info
Downlink synchronisation Uplink synchronisation
NBAP
Iub-FP Iub-FP
Start TX >> Are NBAP, ALCAP and RRC messages carried on the same transport bearers on Iub? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 172
5. UTRAN/5.5 Signaling procedures
E. Direct Transfer The mechanism to transfer signalling from higher layers (NAS signaling) through messages of RRC protocol is called Direct Transfer. UE
Node-B
RANAP
RRC
2. Downlink Direct Transfer (DCCH:FACH or DCH) NAS message
CN
SRNC
1. Direct Transfer CN Domain Indicator, NAS PDU
RANAP
RRC
>> Can you mention some examples of use of Direct Transfer? RRC
1’. Uplink Direct Transfer (DCCH:RACH or DCH)
RRC
CN node indicator, NAS message
RANAP © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
2‟. Direct Transfer CN Domain Indicator, NAS PDU
RANAP Page 173
5. UTRAN/5.5 Signaling procedures
F. Control of RAB, RB, Transport and Physical Channels These procedures take place after RRC connection establishment: the UE is either on cell_FACH or cell_DCH state. A RAB is mapped on one or more RB(s). A RB establishment consists of:
- performing admission control (see RRM: Radio Resource Management) - setting parameters describing RB processing in layer 2 (e.g TFS, TFCS) and in layer 1 (codes, power control) RAB and RB can be reconfigured during an active connection. The transport channels and physical channels parameters are included in the RB but can also be reconfigured separately with transport and physical channel dedicated procedures (Transport Channel Reconfiguration and Physical Channel Reconfiguration). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 174
5. UTRAN/5.5 Signaling procedures
F1. RAB Establishment UE
Node-B
RNC RANAP
1. RAB Assignment Request RAB parameters, User plane mode, Transport Address, Iu Transport association
CN RANAP
2. ALCAP Iu Data Transport Bearer Setup 3. Radio Link Establishment (see Procedure D)
4. RB Setup (DCCH:FACH or DCH ) RRC
TFS, TFCS...
RRC
5. RB Setup Complete (DCCH:RACH or DCH ) RRC RRC -
RANAP
6. RAB Assignment Response -
RANAP
>> Can the UE send user information (e.g voice call) after completing this stage? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 175
5. UTRAN/5.5 Signaling procedures
F2. Physical Channel Reconfiguration UE
Node-B of DRNC NBAP NBAP
DRNC 1. RL Reconfig. Prepare
SRNC
NBAP
DL scrambling code
2. RL Reconfig. Ready
NBAP
-
RNSAP
3. DL scrambling code
RNSAP NBAP RRC RRC
5. RL Reconfig. Commit
4.
RNSAP RNSAP
NBAP
6. Physical Channel Reconfiguration (DCCH:DCH ) DL scrambling code
7. Physical Channel Reconfiguration Complete (DCCH:DCH ) -
RRC RRC
>> What is the difference between NBAP and RNSAP? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 176
5. UTRAN/5.5 Signaling procedures
G. Soft HO (Radio Link Addition) UE
Node-B of DRNC
DRNC
SRNC 1. Decision to setup new RL
RNSAP
2. RL Setup Request -
RNSAP
3. Radio Link Establishment (see Procedure D) 4. ALCAP Iur Data Transport Bearer Setup RNSAP
6. Active Set Update (DCCH:DCH )
RRC
RRC
5. RL Setup Response
-
7. Active Set Update Complete (DCCH:DCH )
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
-
-
RNSAP RRC
RRC Page 177
5. UTRAN/5.5 Signaling procedures
EXERCICE Please complete the procedure diagrams on the following slides by using the elementary procedure previously described
Duration : 10 minutes
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 178
5. UTRAN/5.5 Signalling procedures
Location Update Find the missing procedure names! UE UE detached
CN
RNC
Node-B
0. “Just after switch on” process UE in idle mode
1. ... UE in connected mode
2. ... MM: Location Updating Request MM: Authentication Request MM: Authentication Response
3. Security procedures
4. ... MM: Location Updating Accept 5. ... UE in idle mode © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 179
5. UTRAN/5.5 Signalling procedures
Mobile terminated call Find the missing procedure names! UE
RNC
Node-B
CN
0. “Just after switch on” process
1. ... 2. ... 3. ...
RR: Paging Response MM: Authentication Request MM: Authentication Response 4. Security procedures 5. ... CC: Setup CC: Call Confirm 6. ... 7. ... CC: Alerting CC: Connect CC: Connect Acknowledge © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 180
5. UTRAN
Layer 3 Layer 2 Layer 1
5.1
From Radio Bearers to transport channelsUE
5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signalling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource management (RRM)
5.8
Mobility management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Node B
RNC
Page 181
5. UTRAN/5.6 The Physical Layer
Physical Layer Process Transport Channels
Channel Coding
Convolutional coding, Turbo coding
Radio Frame Segmentation
10 ms frame duration 15 time slots
Transport Channel Multiplexing Physical Channel Mapping
Layer 1
CCtrCH DPDCH, DPCCH, PRACH...
Spreading
Channelization codes Scrambling codes
Modulation
QPSK
Physical Channels spread over 5 MHz bandwidth © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 182
5. UTRAN/5.6 The Physical Layer
Radio Frame Structure …
1 Radio Frame :
= 15 Time Slots
10ms
….
1 Time slot :
= N bits (according to the bit rate after channel coding)
0.6666 ms
1 Bit :
..
= M chips (M is equal to the spreading factor)
The bit rate may be changed for each frame (10 ms). Fast power control may be performed for each time slot (0,666 ms). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 183
5. UTRAN/5.6 The Physical Layer
Transport Channel Multiplexing DCH 1
DCH 2
Channel Coding
Channel Coding
Transport Channel Multiplexing CCTrCH Physical Channel Mapping One Physical Channel (or more if necessary) Two transport channels can be mapped onto the same physical channel (for one user). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 184
5. UTRAN/5.6 The Physical Layer
Physical channels Physical channels are defined by the mechanisms (e.g frequency, code, power, framing...) with which the data are transferred over the physical resources of the air-interface.
• Physical channels are defined mainly by: - a specific carrier frequency - a scrambling code - a channelization code - start & stop instants (giving a time duration, measured in integer multiples of chips) • Physical channels are sent continuously on the air interface between start and stop instants. • Physical channels are separated by means of quasi-orthogonal codes (2 physical channels shall not have the same channelization code / scrambling code combination). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 185
5. UTRAN/5.6 The Physical Layer
Uplink Physical Channels Common Channels Physical Random Access Channel (PRACH) Physical Common Packet Channel (PCPCH)
Mapped on Transport Channels
Node B
Dedicated Channels Dedicated Physical Data Channel (DPDCH)
Mapped on Transport Channels
Dedicated Physical Control Channel (DPCCH)
NOT mapped on Transport Channels
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 186
5. UTRAN/5.6 The Physical Layer
e.g. Uplink DPDCH/DPCCH Data
DPDCH
N data Pilot
DPCCH
N
pilot
bits
Slot #0
N
TFCI
= 2560 chips, 10*2
Slot #1
k
bits
N
FBI
bits
N
TPC
bits
bits (k=0..6)
Slot #i T
TPC
FBI
TFCI
T slot
1 Radio Frame
bits
Slot #14
= 10 ms
DPDCH carries the dedicated data generated at layer 2 (ie the Dedicated Transport Channel DCH). f
DPCCH carries the dedicated signalling of the physical layer, which is required to convey DPDCH. DPCCH is not visible above the physical layer, it is not carried by any transport channels. Under long scrambling code. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 187
5. UTRAN/5.6 The Physical Layer
e.g. Uplink PRACH When attempting to access the network, the mobile has no dedicated code yet and must choose randomly a code in a set of codes. Collisions may occur between two mobiles. radio frame: 10 ms
radio frame: 10 ms
5120 chips #0 Access slot #0 Access slot #1
#1
#2
#3
#4
#5
#6
#7
#8
#9
#10
#11
#12
#13
#14
A mobile can only begin to transmit at a certain access slot (slotted ALOHA).
Random Access Transmission Random Access Transmission
Access slot #7 Access slot #8
Random Access Transmission
15 access slots have been defined (nothing to do with the time slots of the radio frame!).
Random Access Transmission
Access slot #14
The PRACH has a Random Access Transmission to limit risk of collision.
It is based on a Slotted ALOHA approach with fast acquisition indication. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 188
5. UTRAN/5.6 The Physical Layer
Downlink Physical Channels Common Channels Primary Common Control Physical Channel (P-CCPCH) Secondary Common Control Physical Channel (S-CCPCH)
Mapped on Transport Channels
Physical Downlink Shared Channel (PDSCH)
Synchronisation Channel (SCH)
Node B
Common Pilot Channel (CPICH) Page Indicator Channel (PICH)
NOT Mapped on Transport Channels
Acquisition Indication Channel (AICH)
Dedicated Channels Dedicated Physical Data Channel (DPDCH)
Mapped on Transport Channels
Dedicated Physical Control Channel (DPCCH) NOT mapped on Transport Channels © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 189
5. UTRAN/5.6 The Physical Layer
e.g. Downlink DPDCH/DPCCH DPCCH
DPDCH Data1 N data1 bits
TPC N TPC bits T slot
Slot #0
Slot #1
TFCI N TFCI bits = 2560 chips, 10*2
k
DPDCH
DPCCH
Data2 N data2 bits
Pilot N pilot bits
bits (k=0..7)
Slot #i One radio frame,
Slot #14 T f = 10 ms
Similar to uplink, but DPDCH and DPCCH are time-multiplexed. The SF may range from 256 to 8.
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 190
5. UTRAN/5.6 The Physical Layer
e.g. Downlink PCCPCH 256 chips Data 18 bits
( Tx OFF)
Tslot = 2560 chips , 20 bits
Slot #0
Slot #1
Slot #i
Slot #14
1 radio frame: Tf = 10 ms
The Primary CCPCH carries the BCH, which provides system- and cellspecific information (e.g set of uplink scrambling codes) The P-CCPCH is a fixed rate (30 kbps, SF=256) DL physical channel, which provide a timing reference for all physical channels (directly for DL, indirectly for UL). CCPCH is scrambled under the Primary Scrambling code. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 191
5. UTRAN/5.6 The Physical Layer
e.g. CPICH (pilot) Pre-defined symbol sequence Tslot = 2560 chips , 20 bits = 10 symbols
Slot #0
Slot #1
Slot #i
Slot #14
1 radio frame: Tf = 10 ms
CPICH (or Pilot or Beacon) The pilot carries a pre-defined symbol sequence at a fixed rate (SF=256). It is a reference: - to aid the channel estimation at the terminal (time or phase reference) - to perform handover measurements and cell selection/reselection (power reference) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 192
5. UTRAN/5.6 The Physical Layer
e.g SCH and the cell search procedure Slot #0 Primary SCH Secondary SCH
acp i,0
acs
Slot #1 acp acs
Slot #14 acp
i,1
acs
i,14
256 chips 2560 chips One 10 ms SCH radio frame
SCH (Synchronisation Channel) It can be detected by the UE just after switch on, as the SCH consist of a 256 modulated code sequence which is the same for every cell in the system. It is used by the UE in the cell search procedure to get the (downlink) scrambling code of the cell. After cell search procedure, the terminal can read system and cell- specific BCH information. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 193
5. UTRAN/5.6 The Physical Layer
Mapping TransportPhysical Channels BCH PCH
P-CCPCH
Primary Common Control Physical Channel
S-CCPH
Secondary Common Control Physical Channel
FACH RACH
CPCH DSCH DCH
PRACH
Physical Random Access Channel
PCPCH
Physical Common Packet Channel
PDSCH
Physical Downlink Shared Channel
DPDCH
Dedicated Physical Data Channel
Physical channels not mapped on transport channels: DPCCH SCH CPICH PICH AICH
Dedicated Physical Control Channel (uplink and downlink) Synchronisation Channel Common Pilot Channel Page Indicator Channel Acquisition Indication Channel
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 194
5. UTRAN/5.6 The Physical Layer
Example 1: UL 64 kbps data (1) In this example, a RB (Radio Bearer) is mapped (in RLC) on DTCH which is mapped (in MAC) on DCH. The DCH has the TFS (Transport Format Set): Transport block size Transport block set size CRC Coding TTI
640 bits 4*640 bits 16 bits Turbo coding, coding rate = 1/3 40 ms
#4 640
640
640
640
#3 640
640
640
640
#2 640
640
640
640
#1 640
640
640
640
40 ms
This example can be applied for ISDN service. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 195
5. UTRAN/5.6 The Physical Layer
Example 1: UL 64 kbps data (2)
Transport block CRC attachment
#1 640
CRC
#1 640
16
TrBk concatenation
#4 640 #4 640
CRC
16
2624
Turbo coding R=1/3
7872 Tail
Tail bit attachment 7872
1st interleaving
12
7884
Radio frame segmentation
#1 1971
#4 1971
Rate matching #1 1971+N
What is the radio frame length? Can you deduce the spreading factor (SF)?
#4 RM1
1971+N
RM4
To TrCh Multiplexing (see further) Extracted from 3GPP 25.944 © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 196
5. UTRAN/5.6 The Physical Layer
Example 2: UL 3,4 kbps data (1) In this example, a SRB (Signalling Radio Bearer) is mapped (in RLC) on DCCH which is mapped (in MAC) on DCH. The DCH has the TFS (Transport Format Set): Transport block size Transport block set size CRC Coding TTI
148
148
148 bits 0, 148 bits 16 bits CC, coding rate = 1/3 40 ms
148
40 ms
>> Assuming that RLC and MAC overhead in a transport block is 12 bits, can you determine the bit rate of this SRB? © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 197
5. UTRAN/5.6 The Physical Layer
Example 2: UL 3,4 kbps data (2) Transport block 148
CRC
CRC attachment 148 TrBks (B =0,1)
16
TrBks concatenation 164
Tail
Tail bit attachment 164*B
Convolutional Coding, CR = 1/3
8*B
What is the radio frame length? Can you deduce the spreading factor?
516*B
1st interleaving 516*B
Radio frame Segmentation
#1 129*B
#2 129*B
#3 129*B
#4 129*B
Rate matching #1 129*B +NRM1
Extracted from 3GPP 25.944 © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
#2 129*B +NRM2
#3
#4
129*B +NRM3 129*B +NRM4
To TrCh Multiplexing (see further) Page 198
5. UTRAN/5.6 The Physical Layer
UL TrCH multiplexing of 64 kbps and 3,4 kbps data UL 64 kbps data #1
#2
#3
UL 3,4 kbps data #4
#1
#2
#3
#4
TrCH multiplexing #1
#1
#2
#2
#3
#3
#4
#4
2nd interleaving Physical channel mapping ?? kbps DPDCH
15 kbps DPCCH
CFN=4N
CFN=4N+1
CFN=4N+2
CFN=4N+3
CFN=4N
CFN=4N+1
CFN=4N+2
CFN=4N+3
>> On which physical channel are the UL 64 kbps data and the UL 3,4 kbps data? what is the spreading factor mapped? what is the DPDCH bit rate? >> What is carried on DPCCH ?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN
no
5.1
From Radio Bearers to transport channels
5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signalling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource Management (RRM)
5.8
Mobility Management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
yes
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5. UTRAN/5.7 Radio Resource Management (RRM)
RRM purposes RRM is a set of algorithms to manage radio resources: • Maximise the amount of radio resources available Power control algorithms Handover algorithms • Allocation of radio resources Which type of transport channel, transport format should be chosen to meet QoS requirements? • Admission Control In which conditions can a new user be admitted? • Load Control (congestion control) What should be done to avoid congestion? In RRM all layers are involved under RRC control. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.7 Radio Resource Management (RRM)
RRM functions UE dedicated functions, implemented in SRNC and Node B: Selection of radio bearer parameters according to RAB requirements Closed loop power control Handover control RRC states management according to UE traffic volume DL dynamic scheduling on DCH
UTRAN dedicated functions, implemented in CRNC: Radio admission control Code allocation Radio load control Open loop power control
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.7 Radio Resource Management (RRM)
Transport channel allocation strategies
Common channels
Shared channels
Dedicated channels
UL / DL RACH / FACH low setup time, but continuous transmission not maintained no soft HO and no fast PC
Short packets Bursty traffic to be sent immediately
CPCH / DSCH no guarantee of delay no soft HO, but fast PC
Medium packets Bursty and delayinsensitive traffic
DCH / DCH bit rate can be changed during transmission (TFS) soft HO and fast PC
Long packets Constant and variable bit rate traffic with low delay requirement (LCD) High bit rate
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.7 Radio Resource Management (RRM)
Admission and Load Control
Both procedures are handled by CRNC. They are estimated separately for uplink and downlink directions. Admission Control This algorithm is executed when a radio bearer is to be setup or modified. It is based on: •Power transmission criteria (noise increase in UL, transmit capacity in DL) •Number of active users in the frequency band (code management) And performed according to: •The type of required QoS •The current system load Load Control (Congestion Control) This algorithm ensures that the system is not overloaded and remains stable. In case of congestion some actions can be taken. But overload situations should normally be exceptional. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN
Layer 3 Layer 2 Layer 1 UE 5.1
From Radio Bearers to transport channels
5.2
Radio Protocols
5.3
Iu Protocols
5.4
UE identifiers and UE states
5.5
Signalling procedures
5.6
The Physical Layer (on the air interface)
5.7
Radio Resource Management (RRM)
5.8
Mobility management
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Node B
RNC
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5. UTRAN/5.8 Mobility management
General description (1/2) The mobility management enables a user to have access to the subscribed services on the whole coverage of the usual network and possibly visited networks. It is performed as long as the UE remains switched on. It needs a lot of radio and network resources. • UE in idle mode (network mobility) Wherever the UE is located in the network coverage: - the UE should have an access point to the network in the uplink >> Cell reselection mechanisms - the network should be able to reach the UE in the downlink (paging) >> Location Area (LA) / Routing Area (RA) update mechanisms
• UE in connected mode (radio mobility management) A connection to the UTRAN (RRC connection) has been established: this connection should remain, when the UE moves from one cell to another. >> Handover (HO) or cell update mechanisms © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.8 Mobility management
General description (2/2) • UE in idle mode This mode is entered after “just after switch on” process. The UE location is: - known by the CN at LA or RA level - not known by the UTRAN
UE
UTRAN
Detached
“Just after switch on” process Idle mode
• UE in connected mode RRC connection establishment This mode is entered after RRC connection establishment. The UE location is: Connected mode - known by the CN at a LA or RA level (furthermore the MSC or the SGSN Uu knows the SRNC of the UE) - known by the UTRAN at a cell or URA level. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.8 Mobility management
UE in idle mode (1/2) When moving across the network, the UE may have to perform a cell reselection, if the initial cell on which it is camped is no longer available or is no longer the best suited.
?
The cell reselection consists of a selection of candidate cells and a ranking of these cells according to radio criteria.
The cell reselection is performed autonomously by the UE, but the network can influence it by changing the radio parameters used in radio criteria.
These radio parameters are transmitted in the Broadcast Channel (BCH). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.8 Mobility management
UE in idle mode (2/2)
VLR
Location Area
VLR
...
... HLR
SGSN
SGSN
Routing Area
(LA)
(RA)
When camping on a cell, the terminal must register its LA and/or its RA. When the terminal moves across the network, it must update its LA (RA) which is stored in VLR (SGSN) in the Core Network. LA (RA) Update is performed periodically or when entering a new LA (RA). © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.8 Mobility management
UE in connected mode (1/3)
MM mechanisms
Effect during the call
hard HO soft HO hard HO cell update
very short cut no cut very short cut suspended
Cell_PCH
cell update
suspended
URA_PCH
URA update
suspended
Cell_DCH Cell_FACH
Cell update (URA update) consists of updating the MS location information stored in the SRNC. A UTRA originated paging message will therefore be sent only in this cell (this URA) and not in a whole LA or RA. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.8 Mobility management
UE in connected mode (2/3) Soft HO •inter-cell (softer HO, managed by Node-B) •inter Node-B •inter-RNC (SRNS relocation)
Hard HO •intra CDMA-carrier not recommended for dedicated channels, cell 1 but necessary for common channels for which soft HO is not applied cell 2 •inter CDMA-carrier one operator can have two CDMA carriers or more between two different operators •inter-mode FDD-TDD (not provided in R99) •inter-system UMTS-GSM: necessary to provide continuous coverage UMTS-CDMA2000 (in the US?) Cell reselection •Inter-system : UMTS/GPRS (inter/intra carrier, inter/intra RNC) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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5. UTRAN/5.8 Mobility management
UE in connected mode (3/3) A hard handover consists of forwarding a call on another channel which is running on a different carrier. The terminal must make measurements on other frequencies (FFD, GSM or TDD frequencies) whilst holding the on-going connection : - Dual receiver •simple handover operation, but expensive receiver
UTRA cell
GSM cell
- Compressed mode (or slotted mode) •simple receiver, but complicated handover operation •the information is compressed time periodically (a few ms), in order to perform measurements on the other frequencies without losing data Downlink 10ms frame
Compressed frame
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Idle period Page 212
5. UTRAN/5.8 Mobility management
Exercise 1. The cell reselection is easier than the initial cell selection (performed just after switch on): can you find the reason? 2. What is the difference between the cell reselection and the cell update (performed in cell_PCH state)?
3. If there were no LA/RA update mechanisms, what would happen? 4. Is it better to have small or large LA? 5. Why is soft HO not provided in cell_FACH state? 6. In which case is it be better for the network to move a UE to URA_PCH state rather than to cell_PCH state?
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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Appendix • “Just after switch on” process • AMR codec •NBAP elementary procedures •RANAP elementary procedures
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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Appendix/”Just after switch on” process
PLMN selection PLMN selection List of available 1 PLMNs
UE switche d on
1
After switch on, the UE: - scans the entire frequency bandwidths of UTRAN FDD and GSM (cell search procedure for UTRAN FDD )
Selected 2 PLMN
- monitors the broadcast channels (BCCH for UTRAN FDD) to get the PLMN identifiers.
Cell selection
Hence the UE can establish a list of PLMNs which are available in its location.
2
Attachment
In the list of available PLMNs, the UE selects: - the HPLMN (Home PLMN) if it is available - otherwise another PLMN (national or international) according to priority rules possibly stored in the USIM
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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Appendix/”Just after switch on” process
Attachment procedure PLMN selection
3
In the selected PLMN, the UE: - selects the best cell according to radio criteria
- initiates attachment procedure on the selected cell 4 5
Cell selection Attachment 3 request
Attach4 ment result
During the attachment procedure (called IMSI attach for CS domain, GPRS attach for PS domain), the UE indicates its presence to the PLMN for the purpose of using services: - authentication procedure
- storage of subscriber data from the HLR in the VLR (or in the SGSN for PS domain) - allocation of the TMSI (P-TMSI for PS domain)
Attachment 5
Indication of service to the UE © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
The result of the procedure is notified to the UE: - if successful, the UE can access services - if it fails, the UE can only perform emergency calls Page 216
Appendix/AMR codec
AMR codec (for CS domain)
AMR mode
Source coding bit- rate
AMR_12.20 AMR_10.20 AMR_7.95 AMR_7.40 AMR_6.70 AMR_5.90 AMR_5.15 AMR_4.75
12.20 kbit/ s (GSM EFR) 10.20 kbit/ s 7.95 kbit/ s 7.40 kbit/ s (IS-641) 6.70 kbit/ s (PDC-EFR) 5.90 kbit/ s 5.15 kbit/ s 4.75 kbit/ s
Class Class Class A B C 81 65 75 61 58 55 49 42
103 99 84 87 76 63 54 53
60 40 0 0 0 0 0 0
The AMR (Adaptative Multirate) speech codec: - offers 8 AMR modes between 4,75 kbits/s and 12,2 kbits/s - is capable of switching its bit rate every 20 ms upon command of the RNC - is located in the UE and in the transcoder (which is located in the CN) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 217
Appendix/NBAP elementary procedures
NBAP elementary procedures NBAP Functions (see 3GPP 25.433) •Cell Configuration Management. This function gives the CRNC the possibility to manage the cell configuration information in a Node B. •Common Transport Channel Management. This function gives the CRNC the possibility to manage the configuration of Common Transport Channels in a Node B. •System Information Management. This function gives the CRNC the ability to manage the scheduling of System Information to be broadcast in a cell. •Resource Event Management. This function gives the Node B the ability to inform the CRNC about the status of Node B resources. •Configuration Alignment. This function gives the CRNC and the Node B the possibility to verify that both nodes has the same information on the configuration of the radio resources. •Measurements on Common Resources. This function allows the CRNC to initiate measurements in the Node B. The function also allows the Node B to report the result of the measurements.
•Radio Link Supervision. This function allows the CRNC to report failures and restorations of a Radio Link. •Compressed Mode Control [FDD]. This function allows the CRNC to control the usage of compressed mode in a Node B. •Measurements on Dedicated Resources. This function allows the CRNC to initiate measurements in the NodeB. The function also allows the NodeB to report the result of the measurements. •DL Power Drifting Correction (FDD). This function allows the CRNC to adjust the DL power level of one or more Radio Links in order to avoid DL power drifting between the Radio Links. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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Appendix/RANAP elementary procedures
RANAP elementary procedures RANAP Functions (some of them (see 3GPP 25.413)) •Relocating serving RNC. This function enables to change the serving RNC functionality as well as the related Iu resources (RAB(s) and Signalling connection) from one RNC to another. •Overall RAB management. This function is responsible for setting up, modifying and releasing RABs. •Release of all Iu connection resources. This function is used to explicitly release all resources related to one Iu connection. •SRNS context forwarding function. This function is responsible for transferring SRNS context from the RNC to the CN for intersystem forward handover in case of packet forwarding. •Controlling overload in the Iu interface. This function allows adjusting the load in the Iu interface. •Sending the UE Common ID (permanent NAS UE identity) to the RNC. This function makes the RNC aware of the UE's Common ID. •Paging the user. This function provides the CN for capability to page the UE. •Transport of NAS information between UE and CN. This function has three sub-classes: •Controlling the security mode in the UTRAN. This function is used to send the security keys (ciphering and integrity protection) to the UTRAN, and setting the operation mode for security functions. •Controlling location reporting. This function allows the CN to operate the mode in which the UTRAN reports the location of the UE.
•Data volume reporting function. This function is responsible for reporting unsuccessfully transmitted DL data volume over UTRAN for specific RABs. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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Appendix/RSNAP elementary procedures
RSNAP elementary procedures RSNAP Functions (some of them (see 3GPP 25.423)) •Radio Link Management. This function allows the SRNC to manage radio links using dedicated resources in a DRNS; •Physical Channel Reconfiguration. This function allows the DRNC to reallocate the physical channel resources for a Radio Link; •Radio Link Supervision. This function allows the DRNC to report failures and restorations of a Radio Link; •Compressed Mode Control [FDD]. This function allows the SRNC to control the usage of compressed mode within a DRNS; •Measurements on Dedicated Resources. This function allows the SRNC to initiate measurements on dedicated resources in the DRNS. The function also allows the DRNC to report the result of the measurements; •DL Power Drifting Correction [FDD]. This function allows the SRNC to adjust the DL power level of one or more Radio Links in order to avoid DL power drifting between the Radio Links; •CCCH Signalling Transfer. This function allows the SRNC and DRNC to pass information between the UE and the SRNC on a CCCH controlled by the DRNS; •Paging. This function allows the SRNC to page a UE in a URA or a cell in the DRNS; •Common Transport Channel Resources Management. This function allows the SRNC to utilise Common Transport Channel Resources within the DRNS (excluding DSCH resources for FDD); •Relocation Execution. This function allows the SRNC to finalise a Relocation previously prepared via other interfaces. © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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Related Documentation Abbreviations and Acronyms
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 221
Related documentation
English - WCDMA for UMTS, Harri Holma and Antti Toskala, Wiley 2000, ISBN 0 471 72051 8 - UMTS Mobile communications for the future, Wiley 2001, ISBN 0 471 49829 7 - Alcatel Telecommunications Review, 1st Quarter 2001 (“Find your way with 3G”) - 3GPP specifications: ftp://ftp.3gpp.org/Specs/ Francais - UMTS les réseaux mobiles de troisième génération, Editions Eyrolles 2001 (translation of “WCDMA for UMTS” ) - UMTS les origines, l'architecture, la norme, Pierre Lescuyer, Editions Dunod 2001, ISBN 2 10 005195 4 - Revue des Télécommunications d’Alcatel , 1er trimestre 2001 (entièrement consacrée à la 3G) © Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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Abbreviations and Acronyms (1)
AAL ACELP ADN ALCAP AMR ATM
ATM Adaptation Layer Algebraic Code Excited Linear Prediction Abbreviated Dialling Number Access Link Control Application Part Adaptive Multi Rate Asynchronous Transfer Mode
BCCH
Broadcast Control Channel
BCH BHCA BER BLER BMC BM-IWF
Broadcast Channel Busy Hour Call Attempts Bit Error Rate Block Error Rate Broadcast / Multicast Control Broadcast Multicast InterWorking Function Base Station Controller Base Station (sub)System Base Transceiver Station Customized Application for Mobile Enhanced Logic Call Control
BSC BSS BTS CAMEL CC
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
CCCH
Common Control Channel
CCTrCH CDMA CDR CN CPCH CRNC CS CTCH DCA
Coded Composite Transport Channel Code Division Multiple Access Call Detail Record Core Network Common Packet Channel Controlling RNC Circuit Switched Common Traffic Channel Dynamic channel Allocation
DCCH
Dedicated Control Channel
DCH DHO DHT DRAC DRNC DS DSCH DTCH
Dedicated Channel Diversity HandOver Diversity HandOver Trunk Dynamic Resource Allocation Control Drift RNC Direct Sequence Downlink Shared Channel Dedicated Traffic Channel
Page 223
Abbreviations and Acronyms (2)
EDGE ERAN
Enhanced Data rates for GSM Evolution EDGE Radio Access Network (all-IP)
FACH
Forward Access Channel
FBI FDD FDD-DS FDD-MC FER FP FTP GERAN GGSN GPRS GSM GSN GTP GTP-U HO HPLMN
FeedBack Information Frequency Division Duplex FDD-Direct Sequence (FDD1) FDD-Multiple Carrier (FDD2) Frame Error Rate Frame Protocol File Transfer Protocol GSM/EDGE Radio Access Network Gateway GPRS Support Node General Packet Radio Service Global System for Mobile Communications GPRS Support Node (ie SGSN or GGSN) GPRS Tunneling Protocol GPRS Tunneling Protocol-User Plane HandOver Home PLM
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
IETF IMEI IMSI IP IR ISDN L1,L2,L3 LA LCS LLC LQC M3UA MAC MBS MC MExE MM MSC MSP
Internet Engineering Task Force International Mobile Equipment Identity International Mobile Subscriber Identity Internet Protocol Incremental Redundancy Integrated Services Digital Network Layer 1, Layer 2, Layer 3 Location Area Location Services Logical Link Control Link Quality Control SS7 MTP3 User Adaptation layer Medium Access Control Multi-standard Base Station Multiple Carrier Mobile Execution Environment Mobility Management Mobile-services Switching Center Multiple Subscriber Profile Page 224
Abbreviations and Acronyms (3)
MTP3 Message Transfer Part (broadband) MTP-3B Message Transfer Part level 3 NAS Non Access Stratum NBAP Node-B Application Part ODMA Opportunity Driven Multiple Access OSA Open service Architecture OTDOA-IPDL Observed Time Difference of Arrival Idle Period Downlink OVSF Orthogonal Variable Spreading Factor PCCH
Paging Control Channel
PCH PDA PDC PDP PDU PLMN PRACH
Paging Channel Personal Digital Assistant Personal Digital Cellular (2G Japan) Packet Data Protocol Protocol Data Unit Public Land Mobile Network Physical Random Access Channel
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
PS QOS QPSK RA RAB
Packet Switched Quality Of Service Quadrature Phase Shift Keying Routing Area Radio Access Bearer
RACH
Random Access Channel
RAN RANAP RB RL RLC RNC RNS RNSAP RNTI RRC RRM
Radio Access Network RAN Application Part Radio Bearer Radio Link Radio Link Control Radio Network Controller Radio Network Sub-System RNS Application Part Radio Network Temporary Identity Radio Resource Control Radio Resource Management
Page 225
Abbreviations and Acronyms (4)
SAP SAT SDU SF SGSN SHO SIR SMS SPU SRNC SSCOP
Service Access Point SIM Application Toolkit Service Data Unit Spreading Factor Serving GPRS Support Node Soft HandOver Signal to Interference Ratio Short Message Service Signaling Processing Unit Serving RNC Service Specific Connection Oriented Protocol SSCP Signaling Connection Control Part STM Synchronous Transfer Mode TC Transcoder TCP Transport Control Protocol TD-CDMA Time Division & CDMA TDD Time Division Duplex TDMA Time Division Multiple Access
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
TF TFC TFCI TFCS TFS TMSI TPC UDP UICC UMTS USIM USSD URA URAN
USB UTRAN
Transport Format Transport Format Combination Transport Format Combination Indicator Transport Format Combination Set Transport Format Set Temporary Mobile Station Identity Transmission Power Control User Datagram Protocol UMTS Integrated Circuit Card Universal Mobile Telecommunication System UMTS Subscriber Identity Card Unstructured Supplementary Service Data UTRAN Registration Area UMTS Radio Access Network (ETSI) Universal Radio Access Network (3GPP) Universal Serial Bus UMTS Terrestrial Radio Access Network
Page 226
Abbreviations and Acronyms (5)
VC VHE VoIP VP WAP W-CDMA WIM
Virtual Channel Virtual Home Environment Voice over IP Virtual Path Wireless Application Protocol Wideband Code Division Multiple Access WAP Identity Module
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
Page 227
Abbreviations and Acronyms (Standard Organizations) 3GPP 3GPP2 3GIP ANSI ARIB CWTS ETSI IETF IMT ITU T1 TIA TTA TTC UWCC W3C
3rd Generation Partnership Project (WCDMA) 3rd Generation Partnership Project 2 (cdma2000) 3rd Generation partnership for Internet Protocol American National Standard Institute (USA) Association of Radio Industries and Business (Japan) China Wireless Telecommunication Standard group European Telecommunication Standard Institute Internet Engineering Task Force International Mobile Telecommunication International Telecommunication Union Committee T1 telecommunication of the ANSI (USA) Telecommunication Industry Association (USA) Telecommunication Technology Association (Korea) Telecommunication Technology Committee (Japan) Universal Wireless Communications Committee World Wide Web Consortium
© Alcatel University - 8AS 90171 0004 VT ZZA Ed.03
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