Date post: | 13-Apr-2018 |
Category: |
Documents |
Upload: | gerard-anthony-yabyabin |
View: | 212 times |
Download: | 0 times |
of 396
7/27/2019 UMTS Network Systems Overview Both Days
1/396
U101U101 UMTS Network Systems Overview
UMTS Network SystemsOverview
Day 1
7/27/2019 UMTS Network Systems Overview Both Days
2/396
U101U101 UMTS Network Systems Overview
Introductory Session
Introductory Session
7/27/2019 UMTS Network Systems Overview Both Days
3/396
U101U101 UMTS Network Systems Overview
IntroductionsIntroductory Session
Hello
I am Richard Edge, your course presenter
7/27/2019 UMTS Network Systems Overview Both Days
4/396
U101U101 UMTS Network Systems Overview
Introductory Session
Introduction to AIRCOM
Contents and Session Aims
This session is a get to know yousession
It aims to answer the followingquestions:
Who are AIRCOM and why arethey here training us?
Should I be here?
Why am I here?
It also aims to cover the logistics ofthe course
Whens the lunch/coffee/cigarettebreak?
What are we going to learn aboutand when?
Target StudentsCourse Prerequisites
Aims of the Course
Course Schedule andOrganisation
7/27/2019 UMTS Network Systems Overview Both Days
5/396U101U101 UMTS Network Systems Overview
Target Students
This course is aimed at: Engineers and technical specialists familiar with telecommunications and
looking for an introduction to UMTS
Technically orientated managers looking to understand the technologybehind UMTS
Introductory Session
7/27/2019 UMTS Network Systems Overview Both Days
6/396U101U101 UMTS Network Systems Overview
Prerequisites
An understanding of the basic concepts of: Telecommunications Cellular communications
Wireless communications
Introductory Session
7/27/2019 UMTS Network Systems Overview Both Days
7/396U101U101 UMTS Network Systems Overview
Aims of Course
To teach the student about The background to UMTS The basics of CDMA cellular technology
The elements and architecture of a UMTS network
Techniques specific to UMTS
The UMTS air interface
Introductory Session
I t d t S i
7/27/2019 UMTS Network Systems Overview Both Days
8/396U101U101 UMTS Network Systems Overview
Course ScheduleDay 1 Day 2
9:30-10:15
Introductory Session1st/2ndGenerationCellular Systems
Overview
UTRAN
Drinks Break Drinks Break
10:45-11:30
3rdGeneration Driversand Standards
UTRAN (cont.)
Drinks Break Drinks Break
12:00-12:45
CDMA MobileTechnology Overview
UMTS Core Network
Lunch Lunch
13:45-14:30
UMTS ArchitectureOverview
UMTS Fixed NetworkInterfaces
Drinks Break Drinks Break
15:00-15:45
UTRA Air Interface UMTS Mobiles
Drinks Break Drinks Break
16:15-17:00
UTRA Air Interface(cont.)
UMTS Services
17:00-17:30 Day 1 Roundup Course Roundup
Introductory Session
I t d t S i
7/27/2019 UMTS Network Systems Overview Both Days
9/396U101U101 UMTS Network Systems Overview
How the Sessions are Organised
Locator Slide To remind you where you are when you wake up! Theres also a section title at the top left of the slide...
Contents and Aims
New Material for the Session
Questions (please ask anytime!) Questions to You (to make sure youve been listening and understand)
Questions to Me (if you dont understand or want to know more)
Section Summary
Introductory Session
Introductory Session
7/27/2019 UMTS Network Systems Overview Both Days
10/3961U101U101 UMTS Network Systems Overview
Locator Slide
In t roduc tory Session
1st and 2nd Generation CellularSystems Overview
3rd Generation Drivers andStandards
CDMA Mobile TechnologyOverview
UMTS Architecture Overview
UTRA Air Interface
Day 1 Roundup
Day 2 Introductory Session
UTRAN UMTS Core Network
UMTS Fixed Network Interfaces
UMTS Mobiles
UMTS Services
Course Roundup
Introductory Session
Introductory Session
7/27/2019 UMTS Network Systems Overview Both Days
11/3961U101U101 UMTS Network Systems Overview
Questions
Any questions?
Introductory Session
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
12/396
1U101U101 UMTS Network Systems Overview
Locator Slide
Introductory Session
1st and 2nd Generat ion CellularSystems Overview
3rd Generation Drivers andStandards
CDMA Mobile TechnologyOverview
UMTS Architecture Overview
UTRA Air Interface
Day 1 Roundup
Day 2 Introductory Session
UTRAN UMTS Core Network
UMTS Fixed Network Interfaces
UMTS Mobiles
UMTS Services
Course Roundup
1st and 2nd Generation Cellular Systems Overview
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
13/396
1U101U101 UMTS Network Systems Overview
1st and 2nd Generation Cellular Systems Overview
1st and 2nd Generation Cellular SystemsOverview
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
14/396
1U101U101 UMTS Network Systems Overview
Contents and Session Aims1st and 2nd Generation Cellular Systems Overview
This is a background session to setthe scene for UMTS, essentially acellular history lesson
Firstly we will examine what wemean by cellular communications
We will look at differentgenerations of cellular and briefly
at major standards This will allow us to see why 3G
has moved forward in the way thatit has
What is Cellular?
Cellular Generations
1st Generation2nd Generation2.5G
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
15/396
1U101U101 UMTS Network Systems Overview
What is Cellular? There are three major types of
terrestrial mobile communicationstechnologies
Cellular Users are provided wide area
mobility from multiple base stationswith handover permitted
Cordless Communication Users are provided limited mobility
from a dedicated base station
Paging Brief numeric, alphanumeric or voice
messages are sent to the subscribertypically using simulcasting
1st and 2nd Generation Cellular Systems Overview
PSTNMSC
Paging
ControlCentre
Cellular
Cordless
Paging
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
16/396
1U101U101 UMTS Network Systems Overview
Cellular Generations
People talk about mobiletechnology in terms of generations
1st Generation or 1G
2nd Generation or 2G
2.5G
3rd Generation or 3G
But what do these mean?
st a d d Ge e at o Ce u a Syste s O e e
time
Datarate
Progress of data rates withtime and generation
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
17/396
1U101U101 UMTS Network Systems Overview
1st Generation
1976+, though really thetechnology of the 1980s
Analogue modulation
Frequency Division MultipleAccess
Voice traffic only
No inter-network roaming possible Insecure air interface
y
The 1st Generation ofCellular Technology makesuse of analog modulation
techniques such as FM
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
18/396
1U101U101 UMTS Network Systems Overview
1st Generation Standards
AMPS (Analogue Mobile Telephony System) North American Standard in cellular band (800MHz)
TACS (Total Access Communications System) UK originated Standard based on AMPS in 900MHz band
NMT (Nordic Mobile Telephony System) Scandinavian Standard in 450MHz and 900MHz bands
C-450 German Standard in 450MHz band
JTACS (Japanese Total Access Communications System) Japanese Standard in 900MHz band
y
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
19/396
1U101U101 UMTS Network Systems Overview
1st Generation Planning
Macrocellular
High sites for coverage drivenplanning
Antennas above roof height
Frequency planning required
Large cell size
Order 30km Hard handover
Only ever connected to a singlecell
Cellular Networks are commonly
represented as hexagon grids.The above diagram shows howdifferent frequencies are used indifferent cells in a cellular network(different frequencies representedby different colours).For networks with more cells thanfrequencies these must be
planned
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
20/396
2U101U101 UMTS Network Systems Overview
2nd Generation
1990s
Digital modulation Variety of Multiple Access
strategies
Voice and low rate circuit switcheddata
Same technology roaming Secure air interface
The 2nd Generation ofCellular Technology is thefirst to use digital modulation
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
21/396
2U101U101 UMTS Network Systems Overview
GSM
First networks in 1992
European developed standard, but
with worldwide subscriber base Different frequency bands
GSM450, GSM900, GSM1800,GSM1900
Largest 2nd Generation subscriber
base Frequency/Time Division Multiple
Access
Open/Standardised Interfaces
GSM phones from 1999/2000
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
22/396
2U101U101 UMTS Network Systems Overview
GSM Planning Macrocells and microcells
Capacity driven planning
Frequency planning required Optional parameters requiringplanning
Hierarchical Cell Structures
Frequency Hopping
Discontinuous Transmission Power Control
Simple subscriber/traffic analysis Capacity limited by number of
TRXs
Hard Handover
GSM networks use microcells
to provide additional capacity.As with 1st generationnetworks frequency planningis required
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
23/396
2U101U101 UMTS Network Systems Overview
D-AMPS/PDC
TDMA (D-AMPS) North American TDMA/FDMA
based standard based upon AMPS
Predominantly used in North andSouth America
ANSI-41 Core Network
Planning Similar to GSM
PDC Japanese TDMA/FDMA based
standard
Predominantly used in Asia
Planning Similar to GSM
TDMA and PDC phones from1999/2000
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
24/396
2U101U101 UMTS Network Systems Overview
cdmaOne
First networks in 1996
Derived from Qualcomm IS-95 airinterface
Largely American subscriber basewith some Asian networks
Code Division Multiple Access This is in many ways the closest
2nd generation standard to manyof the 3rd generation standards
ANSI-41 core network
Chip rate of 1.2288Mcps
cdmaOne phones from
1999/2000
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
25/396
2U101U101 UMTS Network Systems Overview
cdmaOne Planning
Macrocells and microcells
Single Frequency multiple frequencies for hotspots
Soft Handover (multipleconnections between mobile andnetwork)
Code Planning
Capacity Interference Limited1 Connection
2 Connections
3 Connections
Unlike GSM there is nofrequency planningrequired for cdmaOneHowever soft handovermeans that there arezones where there aretwo/three connections tothe network
World ide Mobile Comm nications in the1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
26/396
2U101U101 UMTS Network Systems Overview
Worldwide Mobile Communications in the1990s
0100
200300400500
600700
1991
1993
1995
1997
1999
2001
Second Generation -D-AMPS
Second Generation -PDC
Second Generation -GSM
Second Generation -cdmaOne
First Generation -Analogue
MillionSubscribers
Year Source:Wideband CDMA for 3rdGeneration Mobile Communications, Artech
House, 1998
1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
27/396
2U101U101 UMTS Network Systems Overview
Worldwide Mobile Subscribers
0
500
1000
1500
2000
1995 2000 2005 2010
European UnionCountries
North America
Asia Pacific
Rest of World
MillionSubscribers
Year Source:Third Generation MobileCommunications, Artech House, 2000
2 G1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
28/396
2U101U101 UMTS Network Systems Overview
2.5G
Now...
Digital modulation Voice and intermediate ratecircuit/packet switched data
Same technology roaming
Secure air interface
Based upon existing dominantstandards such as GSM orcdmaOne
2.5G technologies arebased upon existing 2Gtechnologies but arefocussed at increasingthe maximum data ratesthat the technologies candeliver
HSCSD1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
29/396
2U101U101 UMTS Network Systems Overview
HSCSD
High Speed Circuit Switched Data
Enhancement to the GSM standard Utilises: Multiple channel coding schemes
(4.8kbps, 9.6kbps, 14.4kbps pertimeslot)
Multiple timeslots
Circuit Switched Data rates to57.6kbps (4 slots with 14.4kbpschannel coding per slot)
Nokia Cardphone
GPRS1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
30/396
3U101U101 UMTS Network Systems Overview
GPRS
General Packet Radio Service
Enhancement to the GSM standard Utlilises Multiple Channel Coding Schemes
(9.05kbps, 13.4kbps, 15.6kbps,21.4kbps)
Multiple Timeslots
Packet Switching
Packet Switched Data typically torates of 115kbps
Theoretically 171.2kbps for 8timeslots
Ericsson R520(available 1Q 2001)
Sagem MC850 Alcatel One Touch 700(available October 2000
IS 95B1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
31/396
3U101U101 UMTS Network Systems Overview
IS-95B
Enhancement to cdmaOnestandard
Utilises High rate coding scheme
Combined code channels
packet switching
Packet Switched Data to rates of114kbps Qualcomm PDQ
Smartphone
2G d 2 5G St d d C d1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
32/396
3U101U101 UMTS Network Systems Overview
2G and 2.5G Standards Compared
GSM TDMA cdmaOne PDC
Multiple
Access
TDMA TDMA CDMA TDMA
Modulation GMSK /4-DQPSK QPSK /4-DQPSK
CarrierSpacing
200kHz 30kHz 1.25MHz 25kHz
Frame Length 4.615ms 40ms 20ms 20ms
Slots perFrame
8 6 1 3/6
Frequency
Band
450/ 900/ 1800/
1900
800/ 1900 800/ 1900 850/ 1500
Max DataRate
HSCSD:115kbps
GPRS: 115
172kbps
IS-136+:43.2kbps
IS-95A:14.4kbpsIS-95B:
115.2kbps
28.8kbps
FrequencyHopping
Yes No N/A No
Handover Hard Hard Soft Hard
Questions1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
33/396
3U101U101 UMTS Network Systems Overview
Questions
What defines a 1st generation technology and a 2nd generationtechnology?
What is are the main differences between GSM and cdmaOne?
How do 2.5G standards relate to 2G standards?
Session Summary1st and 2nd Generation Cellular Systems Overview
7/27/2019 UMTS Network Systems Overview Both Days
34/396
3U101U101 UMTS Network Systems Overview
Session Summary
Weve now set the scene - we can start talking about wherepeople want to go from here now
The generations of cellular technology may be summarised: 1G is analog voice
2G is digital voice
2.5G is digital intermediate rate data
You also know its the coffee break nowand to come back at10:45!
Locator Slide3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
35/396
3U101U101 UMTS Network Systems Overview
Locator Slide
Introductory Session
1st and 2nd Generation CellularSystems Overview
3rd Generat ion Drivers andStandards
CDMA Mobile TechnologyOverview
UTRA Architecture Overview
UMTS Air Interface
Day 1 Roundup
Day 2 Introductory Session
UTRAN
UMTS Core Network
UMTS Fixed Network Interfaces
UMTS Mobiles
UMTS Services
Course Roundup
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
36/396
3U101U101 UMTS Network Systems Overview
3rd Generation Drivers and Standards
3rd Generation Drivers and Standards
Introduction and Session Aims
7/27/2019 UMTS Network Systems Overview Both Days
37/396
3U101U101 UMTS Network Systems Overview
Introduction and Session Aims
This session is focussed at lookingat how and why the 3rd Generationstandards have evolved
Firstly we will look at the goals andthe focus of the ITU in IMT-2000
We will then examine what driversfrom the regions and the variousindustry bodies who have an
interest in 3rd Generation Finally we will round up by looking
at the IMT-2000 cellular standards
IMT-2000IMT-2000 spectrum
Drivers from Europe,America and AsiaRegulatory bodies
Standardisation bodiesIndustry associations
3rd Generation CellularStandards
IMT-20003rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
38/396
3U101U101 UMTS Network Systems Overview
IMT-2000
IMT-2000 (International Mobile Telecommunications 2000) is aprogram focussed at providing a single global standard formobile communications
Development started in 1985 as FPLMTS Future Public Land Mobile Telecommunications System
Proposed by the ITU (International Telecommunications Union)
Who does IMT-2000 serve?3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
39/396
3U101U101 UMTS Network Systems Overview
Who does IMT-2000 serve?
Integrating all the following users
fixedcellular
cordless
professional mobile radio
paging
satellite
specialised (aeroplane, etc)IMT-2000 terminaand services
Aspects of IMT-2000 Networks3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
40/396
4U101U101 UMTS Network Systems Overview
Aspects of IMT-2000 Networks
Different aspects oIMT-2000 acces
networks
What are the IMT-2000 goals?3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
41/396
4U101U101 UMTS Network Systems Overview
What are the IMT 2000 goals?
Data Rates
Local area - 2 Mbps In office, stationary
Limited mobility - 384 kbps
Urban pedestrian
Full mobility - 144 kbps
Rural in car
High spectrum efficiency compared to existing systems
High flexibility to introduce new services
IMT-2000 Spectrum3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
42/396
4U101U101 UMTS Network Systems Overview
IMT 2000 Spectrum
1800 20501900 1950 20001850 2100 2150 2200
ITU
(WARC-92)
Europe
Japan
Korea
USA
1885 1980 2010 2025 2110 2170 2200
1920 1980 2010 2025 2110 2170 2200
1920 1980 2110 2170
2110 21701920 1980
1850 1910 1930 1990 2110 2200
MSS MSS
IMT-2000
Land Mobile
IMT-2000
Land Mobile UL
IMT-2000Land Mobile UL
IMT-2000
Land Mobile
IMT-2000
Land Mobile DL
IMT-2000Land Mobile DL
UMTS
Paired UL
UMTS
Paired DL
UMTS
SAT
UMTS
SAT
UMTS
Unpaired
UMTS
Unpaired
IMT-2000
Land Mobile
PCS
UL
PCS
DLReserved
1900
DECTGSM 1800
1880
IMT-2000 Future Spectrum3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
43/396
4U101U101 UMTS Network Systems Overview
IMT 2000 Future Spectrum
ITU
(WRC-2000)
Europe
Japan
Korea
USA
2200 3000600 1000 1400 1800 2400
806 960 1710
1880
2500 2690
890 960 1710
GSM 1800GSM 900
New IMT-2000 New IMT-2000 New IMT-2000
Cellular PCS
IMT-2000 Candidate Technology Evaluation3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
44/396
4U101U101 UMTS Network Systems Overview
IMT-2000 Candidate Technology Evaluation
The ITU issued a request for proposals for the RadioTransmission Technology (RTT) for IMT-2000 to be submitted
in June 1998 Following this a self evaluation of the RTT submitted was
required by September 1998
Candidate technologies were then evaluated according to their
compliance with the goals for IMT-2000
IMT-2000 Candidate Harmonisation3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
45/396
4U101U101 UMTS Network Systems Overview
000 Ca d date a o sat o
A number of technologies were submitted many of which haddistinct similarities
Of course operators were generally keen on a single standardto allow global roaming and economies of scale
Operators Harmonisation Group (OHG)
This led to two partnership projects being set up: 3rd Generation Partnership Project (3GPP)
Dealing with UMTS FDD/TDD and related candidate technologies a
3rd Generation Partnership Project 2 (3GPP2)
Dealing with cdma2000 and related candidate technologies
3G Standardization Environment3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
46/396
4U101U101 UMTS Network Systems Overview
Key Players andtheir relationshipsin the IMT-2000standardisation
environment
IMT-2000 Selected Air Interface Standards
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
47/396
4U101U101 UMTS Network Systems Overview
Five candidate technologies wereeventually selected:
IMT-DS (Direct Spread)UMTS FDD
IMT-MC (Multi Carrier)
cdma2000
IMT-TC (Time Code)
UMTS TDD IMT-SC (Single Carrier)
EDGE/UWC-136
IMT-FT (Frequency Time)
DECT
IMT 2000 Selected Air Interface Standards
IMT-2000 Selected Core Network Standards
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
48/396
4U101U101 UMTS Network Systems Overview
Three candidate technologies willbe used:
GSM MAP Evolved
ANSI-41 Evolved
IP Based
Driven forward by 3GIP
IMT 2000 Selected Core Network Standards
IMT-2000 Standards3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
49/396
4U101U101 UMTS Network Systems Overview
The IMT-200family of standards
North America Drivers3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
50/396
5U101U101 UMTS Network Systems Overview
North America and US influenced countries Dominated by 2G TDMA/cdmaOne
USA has slower growth because recipient party pays Mess of digital systems at 800 and 1900 MHz
US manufacturers have pushed forward growing cdmaOne standard
PCS spectrum overlaps IMT-2000 band
Major Drivers
Spectrum sharing and compatibility with 2G standard
National/International roaming
cdma2000 (cdmaOne operators)
EDGE (TDMA operators)
European Drivers3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
51/396
5U101U101 UMTS Network Systems Overview
Europe and European Influenced Countries GSM provided 2nd generation roaming across Europe
Plenty of Capacity at 1800MHz
IMT2000 band compatible with current spectrum usage leads to nospectrum sharing issues
EU enforced standardisation means UMTS for at least 1 operator percountry
Major Drivers
Higher Data Rates
Continued global dominance of European based standard
UMTS
Japan/Korean Drivers3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
52/396
5U101U101 UMTS Network Systems Overview
Japan and Korea PHS and PDC left Japanese manufacturers isolated
IMT2000 band compatible with current spectrum usage leads to nospectrum sharing issues
Political US relationships...
Major Drivers
Capacity for Voice Global market for cellular infrastructure
UMTS
Cordless Drivers3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
53/396
5U101U101 UMTS Network Systems Overview
You cant get 2Mbps out of the cellular standards
Hence a requirement for cordless style standards UMTS TDD Mode
DECT
Industry Bodies - Radio Regulatory3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
54/396
5U101U101 UMTS Network Systems Overview
ITU (International) http://www.itu.int/
ERO (EU) European Radio Office
http://www.ero.dk/
RA (UK) Radiocommunications Agency
http://www.radio.gov.uk/
FCC (USA) Federal Communications
Commission
http://www.fcc.gov/
Industry Bodies - Trade Associations3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
55/396
5U101U101 UMTS Network Systems Overview
UMTS Forum http://www.umts-forum.org/
GSM Association http://www.gsmworld.com/index1.html
CDMA Development Group http://www.cdg.org/
GSM Suppliers Association http://www.gsacom.com/home.html
Universal Wireless Communications Consortium http://www.uwcc.org/
Industry Bodies - Standards Groups3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
56/396
5U101U101 UMTS Network Systems Overview
3GPP UMTS FDD and TDD
Standards Development
http://www.3gpp.org/
3GPP2 cdma2000
Standards Development
http://www.3gpp2.org/
3GIP IP Core Network
http://www.3gip.org/
Partnership Projects and StandardsOrganisations
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
57/396
5U101U101 UMTS Network Systems Overview
Organisations
Relationshipsbetween thestandardsorganisations
3GPP Member Organisations3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
58/396
5U101U101 UMTS Network Systems Overview
ETSI (EU) http://www.etsi.org/
ARIB (Japan) http://www.arib.or.jp/arib/english/
T1 (USA) http://www.t1.org/
TTC (Japan) http://www.ttc.or.jp/e/
TTA (Korea) http://www.tta.or.kr/
CWTS (China) http://www.cwts.org/cwts/index_eng.html
3GPP2 Member Organisations3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
59/396
5U101U101 UMTS Network Systems Overview
TIA (USA) http://www.tiaonline.org/
TTA (Korea) http://www.tta.or.kr/
TTC (Japan) http://www.ttc.or.jp/e/
ARIB (Japan)
http://www.arib.or.jp/arib/english/
CWTS (China) http://www.cwts.org/cwts/index_eng.html
The Road to 3G3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
60/396
6U101U101 UMTS Network Systems Overview
Possible EvolutioPaths to 3G
HSCSD
3rd Generation Cellular3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
61/396
6U101U101 UMTS Network Systems Overview
2002+
Digital modulation
Voice and high rate data
Multi technology roaming
Secure air interface
Standards
UMTS FDD (CDMA based) UMTS TDD (CDMA based)
cdma2000 (CDMA based)
EDGE (TDMA based)
UMTS FDD
U i l M bil T l i i S F
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
62/396
6U101U101 UMTS Network Systems Overview
Universal Mobile Telecommunications System FrequencyDivision Duplexing Mode
Built onto enhanced GSM core network Utilises:
QPSK modulation
Multiple channel coding and bearer rates
Variable spreading factors and multi-code transmission CDMA
FDD
Asynchronous operation
Data up to rates of 2Mbps (typically less)
UMTS Compared to GSMUMTS GSM
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
63/396
6U101U101 UMTS Network Systems Overview
UMTS GSMCarrier Spacing 5MHz 200kHz
Frequency Reuse
Factor
1 1-18
Power Control
Frequency
1500Hz 2Hz or lower
Quality Control Radio ResourceManagement
algorithms
Frequency Planning
and Network
Optimisation
Frequency Diversity 5MHz bandwidth gives
multipath diversity withrake reciever
Frequency Hopping
Packet Data Load Based PacketScheduling
Time Slot based
Scheduling with GPRS
Transmit Diversity Supported to improvedownlink capacity
Not supported by
standard but may be
applied
UMTS Compared to IS95UMTS IS-95
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
64/396
6U101U101 UMTS Network Systems Overview
UMTS IS-95Carrier Spacing 5MHz 1.25MHz
Chip Rate 3.84Mcps 1.2288Mcps
Power ControlFrequency
1500Hz Uplink 800Hz,Downlink slow
Base Station
Synchronisation
No Yes via GPS
Frequency Inter
Frequency
Handovers
Yes, slotted mode
measurements
Possible but
measurements not
specified
Packet Data Load Based PacketScheduling
Packets as short CS
calls
Radio Resource
Management
Efficient algorithms to
provide QoS
Not required for
speech only
Transmit Diversity Supported to improvedownlink capacity
Not supported by
standard
UMTS TDD3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
65/396
6U101U101 UMTS Network Systems Overview
Universal Mobile Telecommunications System FrequencyDivision Duplexing Mode
Built onto enhanced GSM core network
Utilises: QPSK modulation
Multiple channel coding and bearer rates
CDMA
TDD
Asynchronous operation
Data up to rates of 2Mbps (typically less)
cdma20003rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
66/396
6U101U101 UMTS Network Systems Overview
Built onto ANSI-41 core network
Utilises: QPSK modulation
Multiple channel coding and bearer rates
CDMA
FDD
Multiple carriers on the downlink to allow compatibility with cdmaOne
Synchronous operation
Data up to rates of 2Mbps (typically less)
EDGE3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
67/396
6U101U101 UMTS Network Systems Overview
Enhanced Data for GSM Evolution Sometimes called E-GPRS (Enhanced GPRS)
Enhancement to the GSM and TDMA standards
Utlilises: 8PSK Modulation
Possible 1.6MHz carrier under IS-136
8 Channel Coding Schemes
Multiple Timeslots
TDMA
Data up to rates of 384kbps (typically less)
3rd Generation Standards ComparedUMTS FDD UMTS TDD cdma2000 EDGE
3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
68/396
6U101U101 UMTS Network Systems Overview
MultipleAccess
CDMA CDMA CDMA TDMA
Modulation QPSK QPSK QPSK 8-PSKCarrierSpacing
5MHz (200kHzraster)
5MHz (200kHzraster)
3.75MHzUL/1.25MHz DL
200kHz/1.6MHz
Frame Length 10ms 10ms 20ms 4.615ms
Slots perFrame
15 15 16 8/16/64
MultipleRates
Multi-code,Variable
Spreading Factor
Multi-code, multi-slot
SupplementalChannels, Multiplespreading Factors
Multiple channelcode, multi-slot
Chip Rate 3.84Mcps 3.84Mcps 3.6868Mcps
Max DataRate
2Mbps 2Mbps 2Mbps 521/4750kbps
Synchronous No No Yes Yes
Handover Soft Hard Soft Hard
4th Generation...3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
69/396
6U101U101 UMTS Network Systems Overview
Probably 2005-2007
Broadband data rates in excess of
1Mbps Probably 10MHz+ carriers
...
Questions3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
70/396
7U101U101 UMTS Network Systems Overview
What is IMT-2000 and why is it related to UMTS?
Why do the American operators want cdma2000 and EDGE?
What is the major difference between UMTS and cdma2000?
Session Summary3rd Generation Drivers and Standards
7/27/2019 UMTS Network Systems Overview Both Days
71/396
7U101U101 UMTS Network Systems Overview
In this session we have discussed: The key goals of IMT-2000
The drivers for 3rd generation from the regions
The key industry bodies and their relationships
The four cellular air interfaces for IMT-2000 are:
UMTS FDD
UMTS TDD cdma2000
EDGE
Locator SlideCDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
72/396
7U101U101 UMTS Network Systems Overview
Introductory Session
1st and 2nd Generation Cellular
Systems Overview 3rd Generation Drivers and
Standards
CDMA Mobi le TechnologyOverview
UMTS Architecture Overview UMTS Air Interface
Day 1 Roundup
Day 2 Introductory Session
UTRAN
UMTS Core Network UMTS Fixed Network Interfaces
UMTS Mobiles
UMTS Services
Course Roundup
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
73/396
7U101U101 UMTS Network Systems Overview
CDMA Mobile Technology Overview
Contents and Session AimsCDMA Mobile Technology Overview
Thi i i t
7/27/2019 UMTS Network Systems Overview Both Days
74/396
7U101U101 UMTS Network Systems Overview
This session aims to cover somebasic CDMA terminology andtechnology before dealing withUMTS in more detail
Key generic areas of CDMAinclude
How CDMA works and relates toother multiple access schemes
How the codes are generated andwhat their properties are
Soft Handover - what and how?
The pilot channel
Multiple AccessStrategies Explained
CDMA for Cellular
Codes in CDMA
Soft Handover
The Pilot Channel
Multiple Access Explained
I i i kt il t
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
75/396
7U101U101 UMTS Network Systems Overview
Imagine you are in a cocktail party
Now imagine you are trying to talk to somebody (rather than fighting your way to the punch bowl again...)
If you are trying to listen to somebody you need to be able topick out their speech from everybody elses speech.
Everybody is using the same medium to talk - the air in theroom
Clich Explanation
Thi i M lti l A
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
76/396
7U101U101 UMTS Network Systems Overview
This is Multiple Access Many conversations/channels share the same medium
There are a number of different Multiple Access (MA) strategiesyou can try:
Time Division Multiple Access(TDMA)
Frequency Division Multiple Access(FDMA)
Code Division Multiple Access(CDMA)
TDMA at the Cocktail Party
We divide time into a number of timeslots
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
77/396
7U101U101 UMTS Network Systems Overview
We divide time into a number of timeslots
Everybody takes turns to speak within a timeslot
Once everybody has spoken we go back to the start of the list and beginagain - this is a frame
This ensures that two conversations/channels dont get confused.
Conversation/Channel separation is provided in time.
Bit of problem if people speak late or early We may need guard periodsbetween timeslots when nobody speaks
People need to know when to speak We need signaling to tell people their timeslot
TDMACDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
78/396
7U101U101 UMTS Network Systems Overview
frequency
time
User 1 User 1
Timeslot Period Frame Period
Idealised TDMA(with no guardperiods)
AvailableFrequencyBand
FDMA at the cocktail party
We divide the available frequency band into a number of frequency
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
79/396
7U101U101 UMTS Network Systems Overview
We divide the available frequency band into a number of frequencychannels of the same channel bandwidth
People speak continuouslyat different frequencies/pitches, and useearpieces to filter out frequencies theyre not interested in.
Again this ensures that two conversations dont get confused.
Conversation/Channel separation provided in frequency.
Bit of a problem as the filters arent perfect We may need guard bandsbetween timeslots when nobody speaks
People need to know the frequency of the conversation We need signaling to tell people their frequency channel
FDMACDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
80/396
8U101U101 UMTS Network Systems Overview
fre
quency
time
User 1
Frame Period (we may still needframes/timeslots for signaling)
ChannelBandwidth
Idealised FDMA(with no guardbands)
FDMA/TDMA
Of course we could also be clever and use a combination of
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
81/396
8U101U101 UMTS Network Systems Overview
Of course we could also be clever and use a combination ofTDMA and FDMAlike in GSM
This is commonly referred to as simply TDMA
FDMA/TDMACDMA Mobile Technology Overview
Ti l t P i d F P i d
7/27/2019 UMTS Network Systems Overview Both Days
82/396
8U101U101 UMTS Network Systems Overview
fre
quency
time
ChannelBandwidth
Timeslot Period Frame Period
User 1 User 1 IdealisedFDMA/TDMA (withno guard bands orguard periods)
FH at the Cocktail Party
If we combine TDMA and FDMA and change the frequency of transmission
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
83/396
8U101U101 UMTS Network Systems Overview
If we combine TDMA and FDMA and change the frequency of transmissionevery frame we have Frequency Hopping
Frequency hopping improves the received quality of theconversation/channel
We can tolerate the occasional collision of words:
The next word is almost certain to get through
We can always repeat the odd word
This generally wont have too great an impact on the meaning of the conversation.
This is sometimes called frequency hopping spread spectrum This is because the total bandwidth used for an individual conversation is greater
than that strictly required for the individual conversation
i.e. the spectrum has been spread
Frequency Hopping Spread SpectrumCDMA Mobile Technology Overview
Timeslot Period Frame Period
7/27/2019 UMTS Network Systems Overview Both Days
84/396
8U101U101 UMTS Network Systems Overview
frequency
timeUser 1 User 1
ChannelBandwidth
Timeslot Period Frame Period
Idealised FH (withno guard bands orguard periods)
Frequency Hopping Power SpectrumCDMA Mobile Technology Overview
Power
7/27/2019 UMTS Network Systems Overview Both Days
85/396
8U101U101 UMTS Network Systems Overview
Time AveragedPower Spectrum
Frequency
Frequency
Frequency
Frequency
PowerPower
Power
Instantaneous PowerSpectra for a channel in
different frames
CDMA at the Cocktail Party We can actually be more sophisticated than this.
f f
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
86/396
8U101U101 UMTS Network Systems Overview
If we know the characteristics of the persons voice we can tune in to whatthey are saying and ignore what other people are saying
This is like CDMA where the conversation/channel separation is provided bythe characteristics of the channel
i.e. the code
The only problem is that we do pick up some of the noise from the otherchannels
This limits the number of conversations/channels that can use the same medium
We also need to know the code in use We need signaling to tell people their code
This is sometimes called Direct Sequence Spread Spectrum
CDMA - Direct Sequence Spread Spectrum
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
87/396
8U101U101 UMTS Network Systems Overview
frequency
time
code
Frame Period (we may still needframes/timeslots for signaling)
CDMA Power SpectrumCDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
88/396
8U101U101 UMTS Network Systems Overview
Power Spectrum for theequivalent unspreadchannel
FrequencyFrequency
PowerPower
Power Spectrum postspreading
Note: The power spectrumhas been spread similar tothat in a FrequencyHopping system
More CDMA permutations
Of course we can start getting a bit clever again...
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
89/396
8U101U101 UMTS Network Systems Overview
g g g
CDMA/FDMACDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
90/396
9U101U101 UMTS Network Systems Overview
fre
quency
time
code
IdealisedCDMA/FDMA (withno guard bands)
CDMA/FDMA can be used toprovide multiple carriers OR toprovide Frequency DivisionDuplexing - separate carriers forthe uplink and downlink
CDMA/TDMA/FDMA...CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
91/396
9U101U101 UMTS Network Systems Overview
fre
quency
time
code
IdealisedCDMA/TDMA/FDMA(with no guard bands orguard periods)
Combining CDMA and TDMA can be usedto provide Time Division Duplexing
CDMA SpreadingCDMA Mobile Technology Overview
Essentially Spreading involves changing the symbol rate on the air interface
Spreading Despreading
7/27/2019 UMTS Network Systems Overview Both Days
92/396
9U101U101 UMTS Network Systems Overview
Channel
Tx Bit Stream Rx Bit Stream
Air InterfaceChip Stream
Code Chip Stream Code Chip Stream
Identicalcodes
Spreading Despreading
P P
P
f
f
P
f
f
P
f
Spreading and Despreading
1
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
93/396
9U101U101 UMTS Network Systems Overview
Tx Bit Stream
Rx Bit Stream
Code Chip Stream
Code Chip Stream
Air InterfaceChip Stream
1
-1
X
X
Spreading
Despreading
Spreading
If the Bit Rate is Rb, the Chip Rate is Rc, the energy per bit Ebd th hi E th
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
94/396
9U101U101 UMTS Network Systems Overview
and the energy per chip Ecthen
We say the Processing GainGpis equal to:
Commonly the processing gain is refereed to as the SpreadingFactor
b
ccbR
REE .
b
cp
R
RG
Tx Signal Rx Signal (= Tx Signal + Noise)
CDMA Mobile Technology Overview
Spreading in noise
P
f fP
7/27/2019 UMTS Network Systems Overview Both Days
95/396
9U101U101 UMTS Network Systems Overview
Channel
Spreading Code Spreading Code
Wideband Noise/Interference
Signal Signal
The gain due to despreading of the signal over wideband noiseis the Processing Gain
P
f
f f
P
f
P
f
Types of Codes
There are essentially two types ofcodes used in CDMA networks:
CDMA Mobile Technology Overview
S2
7/27/2019 UMTS Network Systems Overview Both Days
96/396
9U101U101 UMTS Network Systems Overview
Channelisation Codes
Are used to separate channelsfrom a single cell or terminal
Scrambling Codes
Are used to separate cells andterminals from each other ratherthan purely channels
Channelisation/scrambling codesmay be either: short (the length of the code is
equal to the bit period)
long (longer than the bit period)
S1
S3
C1 C2 C3
C1 C2 C3
C1 C2 C3
Channelisation Codes
Channelisation codes are orthogonal and hence providechannel separation
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
97/396
9U101U101 UMTS Network Systems Overview
channel separation
Number of codes available is dependant on length of code Channelisation codes require an equal number of 1s and -1s
to be orthogonal
This is because we use integration to demodulate the signal
Typically channelisation codes are used to spread the signal
Channelisation Code Generation
Channelisation codes can be generated from a Hadamardmatrix
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
98/396
9U101U101 UMTS Network Systems Overview
matrix
A Hadamard matrix is:
Where x is a Hadamard matrix of the previous level
For example 4 chip codes are:
1,1,1,1 1,-1,1,-1
1,1,-1,-1
1,-1,-1,1
xxxx
Note: These two codescorrelate if they are time
shifted
Scrambling Code Generation
Scrambling codes are not orthogonal since they are notsynchronised to each other at the receiver
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
99/396
9U101U101 UMTS Network Systems Overview
synchronised to each other at the receiver
Hence it is sufficient to use Pseudo Random sequences Maximal length sequences used which repeat after 2R-1bits
R relates to the number of taps in the generator
Scrambles signals but can also be used to de-scramble
Sequences with different offsets do not correlate Generate a single code
Plan the offsets on the downlink
Scrambling Code Generation
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
100/396
10U101U101 UMTS Network Systems Overview
1 2 3 R-1 R
1 2 3 4 5 OUTPUT1 0 1 0 1 -
1 1 0 1 0 1
0 1 1 0 1 0
0 0 1 1 0 1
1 0 0 1 1 0
0 1 0 0 1 1
0 0 1 0 0 1
0 0 0 1 0 0
Start valuefor offset
Output sequence: 1,0,1,0,1,1,0,0,1,0,0,0,...
Orthogonality of Codes
If orthogonal mean interference power over a bit is zero
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
101/396
10U101U101 UMTS Network Systems Overview
Sum = 0
=> Orthogonal
Sum = 1
=> Correlated
Sum = -0.75
=> Non-orthogonal
Bit Period Chip Period
X
1
-1
0.25
-0.25
0.25
-0.25
Code
Signal Chip Stream
Bit Value
Multi Channel Spreading and Despreading
CDMA Mobile Technology Overview
P
f fP
7/27/2019 UMTS Network Systems Overview Both Days
102/396
10U101U101 UMTS Network Systems Overview
Channelc1 c1
c2 c2
P
f
P
f
P
f
P
f
P
f
fP
Since the channels are orthogonal the resulting interference isentirely removed by the despreading process
CDMA in Cellular Cellular systems have multipath channels with a delay spread
Channels from the same transmitter are no longer perfectly orthogonal
Ch li ti d l f tl h i d
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
103/396
10U101U101 UMTS Network Systems Overview
Channelisation codes are no longer perfectly synchronised
Downlink Channels on the same cell interfere with each other Worst case scenario can be treated as white noise
Otherwise use orthogonality factor (0.6 in urban macrocells typically)
The orthogonality factor gives the percentage of interference that is rejected
CDMA in Cellular
CDMA Mobile Technology Overview
P P
7/27/2019 UMTS Network Systems Overview Both Days
104/396
10U101U101 UMTS Network Systems Overview
c2 c2
Channelc1 c1
P
f fP
P
f
f
P
P
f
P
f
P
f
P
f
Multipath reduces the orthogonality of the downlink codesresulting in interference between channels from the sametransmitter
Visualising the Processing GainW/Hz W/Hz W/Hz
Ec
IoBefore
SpreadingAfter
Spreading With Noise
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
105/396
10U101U101 UMTS Network Systems Overview
W/Hz W/Hz dBW/HzEb
Io
Io
Eb
Io
Eb/Io
Eb
No
Eb/NoEb
No
W/Hz dBW/Hz
Signal
Intra-cell Noise
Inter-cell Noise
Spreading Spreading With Noise
After
Despreading/
Correlation
Post
Filtering
Orthog = 0
Post
Filtering
Orthog > 0
f f f
f ff
f f
A Channelised Transmitter
Channel 1 Pulse Shaping and
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
106/396
10U101U101 UMTS Network Systems Overview
Bit Stream
Channel 2Bit Stream
Channel 3Bit Stream
gModulation
c1
c2
c3
s1Typically in a multi-channel transmitter,channels are first spread and channelisedusing the channelisation codes, thencombined and finally scrambled together.
Rake Receiver
Correlator Phase Rotator Delay EqualizerI
7/27/2019 UMTS Network Systems Overview Both Days
107/396
10U101U101 UMTS Network Systems Overview
Code Generators
(S & C)
ChannelEstimator
Matched Filter
Q Q
A typical rake receiver with threefingers
CDMA Noise Calculation We can say (approximately - assuming perfect power control)
that the Eb/Nois equal to:
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
108/396
10U101U101 UMTS Network Systems Overview
Where: Eb/No= Energy per bit/Noise Power Spectral Density
M = Number of Users or Codes Used
h= Loading
Gp= Processing Gain
l= Sectorisation Gain
v = Voice activity factor
O = Orthogonality Factor
OvG
MNE pb
111
11
11
0
lh
CDMA Capacity Calculations
The Eb/Norequired to achieve a desired BER can becalculated/simulated for a given receiver
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
109/396
10U101U101 UMTS Network Systems Overview
We can say that the number of users we can support isapproximately equal to:
OvG
N
EM p
required
b1
11
1
11
0
lh
CDMA Capacity Calculations
However imperfect power control will create a 30-40%reduction in the capacity on the uplink (downlink channels will
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
110/396
11U101U101 UMTS Network Systems Overview
always be ideally weighted)
Soft handover also impacts the capacity on the downlink -approximately 20-40% of channels will be required forhandover
Control and pilot channels require transmitted power - again
impacting the downlink
Pilot Channels
Pilot channels are effectively channels used in the cell selectionprocess
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
111/396
11U101U101 UMTS Network Systems Overview
Pilots contain no baseband information - no bits The pilot is spread by the all 1s channelisation code
Effectively the pilot is the scrambling code
The required pilot channel SNR is referred to in Ec/Io
Pilots allow channel estimation In cdmaOne the pilot also gives the mobile phase and timing
information
Soft Handover Soft Handover is where more then one cell is in communication
with a terminal
The cells in communication with the terminal are known as an
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
112/396
11U101U101 UMTS Network Systems Overview
The cells in communication with the terminal are known as an
active set The best serving cell is known as the primary cell- and
maintains the primary channel
Other channels are known as handover channels
The gain associated with soft handover is known as themacrodiversity gain
This occurs due to the uncorrelated nature of fast fading between cellsand the variation in slow fading between cells
Note that slow fading is not entirely uncorrelated for different cells
Hard Handover (e.g.GSM)
RX L
Direction of Travel
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
113/396
11U101U101 UMTS Network Systems Overview
HandoverHysteresis
Margin
RX_Lev
Cell A Cell BA hard handoverbetween cells A and Bin GSM
In a hard handoverthe mobile is onlyever instantaneouslyconnected to a singlecell
Distance
Soft Handover (e.g. in cdmaOne)
Active set = 1 = 2 = 1Pilot Ec/Io
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
114/396
11U101U101 UMTS Network Systems Overview
Pilot Ec/Io
T_ADDT_DROP
Cell A Cell A and Cell B Cell B
Direction of Travel
Add Time Delay Drop Time Delay
A soft handoverbetween cells A and Bin cdmaOne
In a soft handover themobile is may beinstantaneouslyconnected to morethan one cell
Distance
Why Soft Handover is Good in CDMA
Why Soft Handover is Good inCDMA
Near Far Effect
CDMA Mobile Technology Overview
Why Soft Handover is Bad inCDMA
Transmission overhead in backhaul
7/27/2019 UMTS Network Systems Overview Both Days
115/396
11U101U101 UMTS Network Systems Overview
Near- Far Effect
Hard Handover can lead torelatively deep penetration intoneighbour cells
Soft Handover allows PowerControl from all Active Set cells
Probability of dropped call reduced
due to link redundancy in handoverregion
Macrodiversity gain
Transmission overhead in backhaul
Addition of downlink noise into thesystem
Engineering of handover zonesbecomes highly critical
More CDMA at the Cocktail Party - CellBreathing
The more noise the louder you have to speak to hear the same amount ofthe conversation
You get to a point where you cant shout louder and cant have a
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
116/396
11U101U101 UMTS Network Systems Overview
You get to a point where you can t shout louder and can t have aconversation where you are standing
The further away you are the louder you have to speak
If it is noisy only people standing close together can have a conversation
As it gets noisy the area that can be covered by a conversation decreases
If it is quiet then the area covered by a conversation can be larger This is called Cell Breathingand occurs in mobile CDMA networks
Cell Breathing An increase in traffic results in an increase in interference
Mobiles at the extremities of cells may be pushed out of thecells effective coverage area due to decreased E /N
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
117/396
11U101U101 UMTS Network Systems Overview
cells effective coverage area due to decreased Eb/No
This effect may occur over the course of 24 hours due tochanges in traffic demand over peak hours
6am Noon 9pm
More CDMA at the Cocktail Party - PowerControl
If somebody is shouting louder than they need it increases theoverall noise
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
118/396
11U101U101 UMTS Network Systems Overview
This is inefficient as it reduces the number of people who canhave conversations
We need to speak as quietly as possible to maximise thenumber of simultaneous
This is called Power Controlin mobile networks
In CDMA networks it is very important that this power control isefficient
We use fast power control with a much quicker feedback loop than inTDMA networks
Power Control
The Near-Far Effect
If equal transmit powersR i d Si l St th f Path Loss = 150dB
MSb
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
119/396
11U101U101 UMTS Network Systems Overview
Received Signal Strength fromMSa higher than required
MSb Eb/Nosignificantly reduced
Near mobiles dominate on theuplink
Cell area and capacity reduced
Solution Fast power control
Large Dynamic Range for mobiles
Path Loss = 150dB
Path Loss = 100dB
MSa
Questions
What is a pilot channel?
How does soft handover differ from hard handover?
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
120/396
12U101U101 UMTS Network Systems Overview
How do scrambling codes differ from channelisation codes? Why is multipath fading bad from a CDMA point of view?
Session Summary
In this session we have discussed: CDMA and how it relates to and differs from other multiple access
technologies
CDMA Mobile Technology Overview
7/27/2019 UMTS Network Systems Overview Both Days
121/396
12U101U101 UMTS Network Systems Overview
technologies
What channelisation and scrambling codes are and what they do
What we mean by a pilot channel
How soft handover works
What we mean by cell breathing and the near far effect
Locator Slide
Introductory Session
1st and 2nd Generation CellularSystems Overview
Day 2 Introductory Session
UTRAN
UMTS Core Network
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
122/396
12U101U101 UMTS Network Systems Overview
Systems Overview
3rd Generation Drivers andStandards
CDMA Mobile TechnologyOverview
UMTS A rch itecture Overview
UMTS Air Interface
Day 1 Roundup
UMTS Core Network
UMTS Fixed Network Interfaces
UMTS Mobiles
UMTS Services
Course Roundup
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
123/396
12U101U101 UMTS Network Systems Overview
UMTS Architecture Overview
Contents and Session Aims
UMTS Architecture Overview
This session aims to give the usera first pass overview of thearchitecture behind UMTS
UMTS High LevelArchitecture
7/27/2019 UMTS Network Systems Overview Both Days
124/396
12U101U101 UMTS Network Systems Overview
To explain the major architecturalblocks
To give a first introduction to themajor network elements andinterfaces
To talk about how UMTS will
interface with existing technologies
The Core NetworkUTRANThe User Equipment
Interfaces
Access ModesUMTS and GSM
Public Land Mobile Network (PLMN) A Public Land Mobile Network is
defined in the specifications asconsisting of:
One or more switches with a
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
125/396
12U101U101 UMTS Network Systems Overview
common numbering plan androuting plan
Switches act as the interfaces toexternal networks
A PLMN can be regarded as anindependent telecommunications
entity The PLMN can be separated into
Core Network
Access Network
Core Network
Access Network
PLMN
UMTS Architecture Overview
UMTS High Level Architecture
To this definition, the 3GPP standards add an additionalarchitectural block, the User Equipment
7/27/2019 UMTS Network Systems Overview Both Days
126/396
12U101U101 UMTS Network Systems Overview
User EquipmentUMTS
Terrestrial Radio
Access Network
Core Network
UU IUUE UTRAN CN
Major Network Elements in UMTS
USIM
Node B
Node BRNC MSC/VLR GMSC
PLMN,PSTN,
UMTS SIM
Radio NetworkController
GatewayMSC
MobileSwitching
Centre
Iu-cs
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
127/396
12U101U101 UMTS Network Systems Overview
UU IU
UE UTRAN CN
CUIUb
IUr
US
ME
ode
Node B
Node BRNC SGSN GGSN
HLR
ISDN
Internet,
X25PacketNetwork
MobileEquipment
Radio NetworkController
Serving GSNGateway
GSN
Home LocationRegister
Iu-ps
IUb
Functions of the CN
Switching
Service Provision
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
128/396
12U101U101 UMTS Network Systems Overview
Transmission of user traffic between UTRAN(s) and/or fixednetwork
Mobility Management
Operations, Administration and Maintenance
Major Elements of the Core Network
Home Location Register (HLR) The database storing the master copy of a users profile
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
129/396
12U101U101 UMTS Network Systems Overview
Visitor Location Registor (VLR) The database holding a copy of a visiting users profile
Mobile Switching Centre (MSC) Switch for Circuit Switched Services
Gateway MSC Serving GPRS Support Node
Router for Packet Switched Services
Gateway GSN
General Core Network Architecture
MSC/VLR GMSC
GatewayMSC
MobileSwitching
Centre
Other MSC
UTRAN
External Circuit
SwitchedIu-cs
UMTS Architecture Overview
FF
7/27/2019 UMTS Network Systems Overview Both Days
130/396
13U101U101 UMTS Network Systems Overview
IU
CN
MSC/VLR
SGSN GGSN
GMSC
HLR
Serving GSNGateway
GSN
Home LocationRegister
Other SGSN
UTRAN
Networks
External Packet
Switched
Networks
Iu-ps
Gs
GnGn
Gr Gc
DD
Gi
Functions of UTRAN
Provision of Radio Coverage
System access control
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
131/396
13U101U101 UMTS Network Systems Overview
Security and privacy Handover
Radio resource management and control
Elements of UTRAN
Radio Network Controller Owns and controls radio resources in its domain
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
132/396
13U101U101 UMTS Network Systems Overview
Service Access point for all services that UTRAN provides the CN Node B
Acts as the radio basestation
Converts the data flow bewteen the Iuband Uuinterfaces
General UTRAN Architecture
Node B
Node BRNC
Radio NetworkController
Iu-cs
UMTS Architecture Overview
CN (MSC)
7/27/2019 UMTS Network Systems Overview Both Days
133/396
13U101U101 UMTS Network Systems Overview
UU IU
UTRAN
IUb
IUr
Node B
Node BRNC
Radio NetworkController
Iu-ps
IUb
CN (SGSN)
UE
Functions of the UE
Display and user interface
To hold the authentication algorithms and keys
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
134/396
13U101U101 UMTS Network Systems Overview
User end termination of the air interface Application platform
Elements of the UE
Mobile Equipment The radio terminal used for radio communication over the Uuinterface
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
135/396
13U101U101 UMTS Network Systems Overview
UMTS Subscriber Identity Module The smartcard that holds the subscriber identity, authentication and
encryption keys etc
Additionally one can define a Terminal Equipment item that sitswith the UE
This carries the application specific user interface
The interface for the TE may be provided by Bluetooth for example
General UE Architecture
USIM
UMTS SIM
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
136/396
13U101U101 UMTS Network Systems Overview
UU
UE
CU
ME
MobileEquipment
UTRANTerminal
Equipment
Major Interfaces in UMTS
There are four major newinterfaces defined in UMTS
Iu
UMTS Architecture Overview
CN
I
7/27/2019 UMTS Network Systems Overview Both Days
137/396
13U101U101 UMTS Network Systems Overview
The interface between UTRANand the CN
Iur
The Interface between differentRNCs
Iub
The interface between the Node Band the RNC
Uu
The air interface
RNC
Node-
B
RNC
UE
Uu
u
Iub
Iur
Iu - the Core Network to UTRAN Interface There are two parts to the Iu
interface
Iu-psconnecting UTRAN to the PS
D i f th CN
UMTS Architecture Overview
CN
I
7/27/2019 UMTS Network Systems Overview Both Days
138/396
13U101U101 UMTS Network Systems Overview
Domain of the CN Iu-csconnecting UTRAN to the CS
Domain of the CN
No radio resource signalling travelsover this interface
The Iuinterface divides the UMTS
network into the radio specificUTRAN and the CN responsible forswitching routing and serviceprovision
RNC
Node-
B
RNC
UE
Uu
u
Iub
Iur
Iur- the Inter-RNC Interface The Iurinterface allows soft
handovers between Node-Bsattached to different RNCs
It i i t f t ll th
UMTS Architecture Overview
CN
I
7/27/2019 UMTS Network Systems Overview Both Days
139/396
13U101U101 UMTS Network Systems Overview
It is an open interface to allow theuse of RNCs from differentmanufacturers
Its functions may be summarised: Support of basic inter-RNC mobility
Support of Dedicated and CommonChannel Traffic
Support of Global ResourceManagement
RNC
Node-
B
RNC
UE
Uu
u
Iub
Iur
Iub- the RNC to Node-B Interface The Iubis an open interface to allow
the support of differentmanufacturers supplying RNCsand Node-Bs
UMTS Architecture Overview
CN
I
7/27/2019 UMTS Network Systems Overview Both Days
140/396
14U101U101 UMTS Network Systems Overview
Its major functions are: Carries dedicated and common
channel traffic between the RNCand the Node-B
Supports the control of the Node-B
by the RNC
RNC
Node-
B
RNC
UE
Uu
u
Iub
Iur
Uu- the Air Interface Clearly the Uumust be
standardised to allow multiple UEvendors to be supported by anetwork
UMTS Architecture Overview
CN
Iu
I
7/27/2019 UMTS Network Systems Overview Both Days
141/396
14U101U101 UMTS Network Systems Overview
The major functions of the Uuareto:
Carry dedicated and commonchannel traffic across the airinterface
Provide signaling and control trafficto the mobile from the RNC and theNode-B
RNC
Node-
B
RNC
UE
Uu
Iub
Iur
UMTS Interface Implementation
NodeB
SGSN
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
142/396
14U101U101 UMTS Network Systems Overview
ATM/IP Network
RNCNodeB
NodeB
MSC
RNC
NodeB
IubIu_csIu_psIur
Access Modes for UMTS
In this course we will concentrate on the UMTS FDD airinterface
However we should bear in mind that a number of other accessmodes are possible
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
143/396
14U101U101 UMTS Network Systems Overview
modes are possible
Within UTRAN
Outside of UTRAN
Access Modes within UTRAN
There are four access modes that will be contained withinrelease 2000 of the 3GPP standards
Direct Sequence FDD Mode 1
Based on UMTS FDD air interface
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
144/396
14U101U101 UMTS Network Systems Overview
Based on UMTS FDD air interface
Multi Carrier FDD Mode 2
Based on cdma2000
TDD Mode
Based on UMTS TDD air interface
ODMA
Supplement to UMTS TDD mode based on using a second UE as a radiorelay
Additional Access Networks The UMTS CN is being
designed with the possibility ofinterfacing to additional AccessNetworks other than UTRAN
GRAN GSM/GPRS Radio
UMTS-CN
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
145/396
14U101U101 UMTS Network Systems Overview
GRAN - GSM/GPRS RadioAccess Network
ERAN - EDGE Radio AccessNetwork
BRAN - Broadband RadioAccess Network (HIPERLAN2)
DECT - Digital EnhancedCordless Telephony
DECT
BRAN GRAN
ERAN
UTRAN
UMTS and GSM
Core
NetworkSGSN MSC
Internet PSTN
GGSN GMSC
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
146/396
14U101U101 UMTS Network Systems Overview
RBS
RNC
Node-B
Iub
RBS RBS RBS
RNC
Node-B Node-B
UTRAN
SGSN MSC
Iu-csIu-psIu-cs
Iu-ps
IubIub
BSC
BTS
Iur
A-bis
A
GbBSS/
Architecture of a UMTS bearer serviceTE TEUE UTRAN
CNedge node
CNgateway
End-to-End Service
TE/UE Local External Bearer
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
147/396
14U101U101 UMTS Network Systems Overview
TE/UE LocalBearer Service UMTS Bearer Service
Radio Access Bearer Service
External BearerService
CN BearerService
Radio Bearer
Service
IuBearer ServiceBackbone Network
Service
UTRA FDD/TDDService
Physical BearerService
UMTS Protocol Stratums In order to provide separation
between radio accessfunctionality and service qualityprovision, protocols in UMTS
are divided into two stratums
NonAc
ces L6 L6
L7 L7
7/27/2019 UMTS Network Systems Overview Both Days
148/396
14U101U101 UMTS Network Systems Overview
are divided into two stratumsAccess Stratum
Encompasses layers 1 and 2of the OSI 7 layer model, andthe lower part of layer 3
Non-access Stratum
Encompasses layers 4 to 7of the OSI 7 layer model, andthe upper part of layer 3
ssStratum
AccessStratum
L1 L1 L1L1
L2L2L2
L2
L5L5
L4L4
L6 L6
L3 lower L3 lower L3 lower L3 lower
L3 upper L3 upper
Uu IuUE UTRAN CN
Questions What elements does UTRAN consist of?
What is the primary role of UTRAN?
What additional access modes does UMTS support over UMTSFDD?
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
149/396
14U101U101 UMTS Network Systems Overview
What additional access modes does UMTS support over UMTSFDD?
Session Summary In this session we have discussed the major elements of the
UMTS network architecture
In following sessions we will discuss each element in moredetail
UMTS Architecture Overview
7/27/2019 UMTS Network Systems Overview Both Days
150/396
15U101U101 UMTS Network Systems Overview
detail
Locator Slide Introductory Session
1st and 2nd Generation CellularSystems Overview
3rd Generation Drivers andSt d d
Day 2 Introductory Session
UTRAN
UMTS Core Network
UMTS Fixed Network Interfaces
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
151/396
15U101U101 UMTS Network Systems Overview
3rd Generation Drivers andStandards
CDMA Mobile TechnologyOverview
UMTS Architecture Overview
UMTS Air Interface Day 1 Roundup
UMTS Fixed Network Interfaces
UMTS Mobiles
UMTS Services
Course Roundup
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
152/396
15U101U101 UMTS Network Systems Overview
UMTS Air Interface
Contents and Session Aims
UMTS Air Interface
This session aims to explain theprotocols and operation of the airinterface
To give an overview of the UMTSspecific operation of the air
Overview of the AirInterface
Logical Transport and
7/27/2019 UMTS Network Systems Overview Both Days
153/396
15U101U101 UMTS Network Systems Overview
p pinterface
To look at the protocol structure
To investigate the Frame andTimeslot structure of the major airinterface channels
Logical, Transport andPhysical Channels on the
Air Interface
The Dedicated Channels
Role of the Air Interface To provide a number of bearer or physical channels to support
data transfer over the radio path.
To provide control channels to manage the cell
To provide a number of traffic channels at an acceptable errorf d t i t
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
154/396
15U101U101 UMTS Network Systems Overview
To provide a number of traffic channels at an acceptable errorperformance and at various rates
To provide signalling channels for call set up, etc.
In providing all of this to also:
Ensure an efficient use of the available spectrum Minimise interference to other cells and services
Minimise the use of power, particularly from the mobile
Provide synchronisation
UMTS FDD Air Interface Overview
Parameter ValueMultiple Access Scheme Direct Sequence CDMA
Duplexing Method FDD
Chip Rate 3.84 McpsCarrier Spacing 5 MHz
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
155/396
15U101U101 UMTS Network Systems Overview
Carrier Spacing 5 MHz
Carrier Spacing Raster 200 kHz
Frame Length 10 ms
Slots per Frame 15
Inter-cell Synchronisation None
Spreading factor Variable (4-512)
User Data Rate 8->384 kbps
Multiple Access Scheme UMTS FDD mode makes use of a CDMA style multiple access
scheme
In the case of UMTS this is commonly referred to as WidebandCDMA
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
156/396
15U101U101 UMTS Network Systems Overview
However there are elements of FDMA and TDMA in UMTS Common channels for paging and packet access share codes between
UEs (TDMA)
Multiple carriers are used per operator (FDMA)
Duplexing Method UMTS FDD mode makes use of
Frequency Division Duplexing
The Uplink and DownlinkChannels are carried on
separate carriers
UMTS Air Interface
190MHz
7/27/2019 UMTS Network Systems Overview Both Days
157/396
15U101U101 UMTS Network Systems Overview
In the case of UMTS in Europe: The Uplink band is between 1.92
and 1.98GHz
The Downlink band is between
2.11 and 2.17GHz The Uplink/Downlink Separation
is 190MHz
UMTS Uplink UMTS Downlink
Chip Rate The chiprate used in UMTS FDD mode is 3.84Mcps
This leads to a carrier bandwidth of approximately 5MHz
This chip rate was chosen because it: Could be generated simply from existing GSM clock rates
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
158/396
15U101U101 UMTS Network Systems Overview
Provided a similar bandwidth to cdma2000 to allow shared use of filters etc inUEs
Note:Initially UMTS was specified as having a chip rate of 4.096Mcps. You may find some old texts and papers referring to this chip rate
Carrier Spacing and Carrier Spacing Raster The nominal carrier spacing for
UMTS is 5Hz
This was chosen to comply with
the American market, wherespectrum has been awarded in
UMTS Air Interface
5MHz
7/27/2019 UMTS Network Systems Overview Both Days
159/396
15U101U101 UMTS Network Systems Overview
p5MHz blocks
It is possible to move the centrefrequency of the carrier on a200kHz raster
We can have carrier spacingsbetween 4.4MHz and 5.6MHz
This may be set within the licenseconditions, or to the operatorsdiscretion
200kHz
Adjacent Channel Interference Adjacent channel interference may have a significant impact on
UMTS capacity
Required attenuation (by standards) adjacent carrier 33dB
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
160/396
16U101U101 UMTS Network Systems Overview
2nd adjacent carrier 43dB
Since only have 2 or 3 carriers typically at least one adjacentcarrier will be transmitted by a third party
This can partially be negated by a flexible carrier spacing basedupon a 200kHz raster
Adjacent Operator Interference
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
161/396
16U101U101 UMTS Network Systems Overview
Distant ServingMacrocell
Close InterferringMicrocell
Interference
Signal50dB path loss
150dB path loss
UK Spectrum Allocations ExampleD D DE E EC C CA A A A B B B
Hutchison Vodafone Orange
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
162/396
16U101U101 UMTS Network Systems Overview
One2One BT Cellnet
g
14.6MHz 14.8MHz10MHz 10MHz 10MHz0.3MHz0.3MHz
20MHz
Radio Frame Structure Radio Frame Period = Tf = 10ms
Frames are used for channel format control
15 slots, #0#14 Slots are use for power control
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
163/396
16U101U101 UMTS Network Systems Overview
Tslot
= 666.7ms = 2560 chips
Slots are use for power control
38400 chips
Tslot= 2560 chips = 666.7ms
#0 #1 #2 #i #14
Tf = 10ms = 38400 chips
Superframe Structure 72 Radio Frames make a Superframe
Superframes are used for
Superframe Period Tsf= 720ms
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
164/396
16U101U101 UMTS Network Systems Overview
#0 #1 #2 #i #71
Tsf = 720ms
Inter Cell Synchronisation Cells in a UMTS network are not synchronised in time with
each other.
This removes the need for tight synchronisation between thebase stations
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
165/396
16U101U101 UMTS Network Systems Overview
There is no need for GPS receivers at sites This makes implementation of picocells and their integration with the
network more simple as satellite LoS is not required
3rd Party Transmission requirement are less stringent
Spreading Factor and User Data Rates UMTS has been designed to provide flexibility to allow the user
to use multiple services, some of which we cannot foresee atthe moment
Rather than having a fixed bit rate and spreading factor, eachof the channels on the user interface has a range of bit rates
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
166/396
16U101U101 UMTS Network Systems Overview
of the channels on the user interface has a range of bit ratesthat can be used
This makes the channels more complicated than for GSMbutcertainly more flexible
Air Interface Access StratumL3
Radio ResourceControl RRC
Radio LinkControl RLC
Control Plane
SignallingUser Plane
Information
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
167/396
16U101U101 UMTS Network Systems Overview
L2
L1
Medium AccessControl MAC
Physcial Layer
Logical Channels
TransportChannels
Physical
Channels
Radio Resource Control Layer The RRC layer forms the lower
part of the OSI layer 3
It is responsible for:
Bearer Control Monitoring
L3 Radio ResourceControl RRC
Radio LinkControl RLC
Control Plane
SignallingUser Plane
Information
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
168/396
16U101U101 UMTS Network Systems Overview
Physical
Channels
Power Control
Measurement Reporting
Paging
Broadcast Control
L2
L1
Medium AccessControl MAC
Physical Layer
Logical Channels
Transport
Channels
Radio Resource Control Layer FunctionalEntities
The RRC layer resides at the RNC serving a cell or UE
The RRC Layer can be split into 3 functional entities Dedicated Control Functional Entity (DCFE)
One per UE in connection
f f
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
169/396
16U101U101 UMTS Network Systems Overview
All functions and signalling specific to a single UE
Paging and Notification control Functional Entity (PNFE)
One per cell
Paging of idle mode UEs
Broadcast Control Functional Entities (BCFE)
One per cell
Broadcasting of system information
Radio Link Control Layer The RLC layer forms the upper
part of the OSI layer 2
It is responsible for:
Logical Link ControlAcknowledged and
k l d d d t t f
L3 Radio ResourceControl RRC
Radio LinkControl RLC
Control Plane
SignallingUser Plane
Information
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
170/396
17U101U101 UMTS Network Systems Overview
Physical
Channels
unacknowledged data transfer L2
L1
Medium AccessControl MAC
Physical Layer
Logical Channels
Transport
Channels
The Medium Access Control Layer The MAC Layer forms the lower
part of layer 2
It is responsible for:
Random Access Physical Link Control
L3 Radio ResourceControl RRC
Radio LinkControl RLC
Control Plane
SignallingUser Plane
Information
UMTS Air Interface
7/27/2019 UMTS Network Systems Overview Both Days
171/396
17U101U101 UMTS Network Systems Overview
P