INTRODUCTION Analogue mobile systems are commonly referred to as “First
Generation” (e.g. AMPS).
Digital systems currently in use, such as GSM, CDMA one IS-95 are second generation or 2G Systems
Third generation (3G) mobile systems are designed for multimedia
communication, enhanced high quality image video and access
to information services
Multimedia communications require higher bandwidth than what 2G can offer.
1G Analogue or Amps Frequency modulation For voice transmission
2G CDMA IS-95, GSM FDMA, TDMA, CDMA Voice plus Data services
Cellular Generations
3G WCDMA, CDMA2000 High service flexibility compatibility QOS
1980 1990 2000
Multiple Access Methods
User 1
User 2
User 3
Guard Band
Guard Band
time
FDMA
User2
User1
User3
User3
User3
User1
User1
User2
User2
time
CDMA (FH)
Use
r 1
Use
r 2
Use
r 3
Gua
rd B
and
Gua
rd B
and
time
freq
uenc
y
TDMA
CDMA
CDMA
Pure CDMA Hybrid CDMA
THDS FH
Slow FH Fast FH
NarrowbandWideband
TDMA/CDMA
DS/FH/TH MC/MT-CDMA
The 3G Choice is CDMA
Since 3G CDMA efficiently provides high quality voice services and high-speed packet data access, it is the preferred technology for 3G.
The 3G operating modes, WCDMA and CDMA2000 are all by far the most dominant in terms of current commercial services, operator deployment plans and vendor support.
Conceptual Network Model
User Equipment (UE)Mobile Equipment (ME)UMTS Service Identity Module (USIM)
Radio Access Network (RAN)UTRANGERAN
Core Network (CN)Circuit Switched (CS)Packet Switched (PS)
UMTS High-Level System Architecture
UE UTRAN CN
Uu Iu
UE: User EquipmentCN: Core NetworkUTRAN: UMTS Terrestrial Radio Access Network
PLMN Elements
USIM: UMTS Subscriber Identity ModuleME: Mobile EquipmentRNE: Radio Network ControllerCu, Uu, Iub, Iur, Iu are interface specifications
USIM
ME
Node B
Node B
Node B
Node B
RNC
RNC
MSC/ VLR GMSC
SGSN GGSN
HLR
PLMN, PSTN,
ISDN, etc.
Internet
Uu Iu
UE UTRAN CN External Networks
Cu IurIub
What is WCDMAWCDMA is a Wideband Direct-Sequence Code Division Multiple Access (DS-CDMA) system.
Information bits are spread over a wide bandwidth by multiplying the it with pseudo-random bits called chips derived from CDMA spreading codes.
The chip rate of 3.84 Mcps used in WCDMA leads to a carrier bandwidth of approximately 5 MHz.
Narrowband CDMA (IS-95) occupies a bandwidth of 1.25 MHz.
Signal Spreading
1
-1
1
-1
Data
PN
1
-1
SpreadData
Signal Spreading/Despreading
ChannelData Rb(bits/s)
PN SequenceSpreading codeRc(chips/s)
PN SequenceSpreading codeRc(chips/s)
Data Rb(bits/s)
PN: Pseudorandom Noise
Tx Rx
Pow
er
Frequency
Pow
er
Frequency
Pow
er
Frequency
Pseudorandom Codes
The ideal spreading code would be an infinite sequence of equally likely random binary digits.In practice, periodic pseudorandom codes are used instead (PN codes).Specific PN codes include:
maximal-length codeGold codes
Multipath Delay Profile
MS Transmit Power Control
One of the most important aspects of CDMA is a tight and fast power control, in particular uplink.
Without power control,a single over powered mobile could lock the entire cell.
Fast closed-loop power control algorithm is used in WCDMA.
Closed-Loop Power Control
MS2
MS1
power controlcommands to the mobiles
P1
P2
near
far
Cell HandoverCell Handover
f2
f1
Traditional ‘Hard’ handover in GSM
BSC
Cell HandoverCell Handover
f1
f1
‘Soft’ handover in UMTS
RNC
FUTURE SERVICES
Mobile Broadband WCDMAMobile Broadband WCDMA
WCDMA for Mobile Broadband services WCDMA for Mobile Broadband services provides key benefits like user provides key benefits like user convenience with its "everywhere convenience with its "everywhere coverage" and ADSL-like data speeds. coverage" and ADSL-like data speeds.
It also offers time to market and cost It also offers time to market and cost advantages for WCDMA operators that advantages for WCDMA operators that can build on their infrastructure assets. can build on their infrastructure assets.
Mobile Broadband WCDMAMobile Broadband WCDMA
WCDMAWCDMA WCDMA technology gives you a WCDMA technology gives you a faster data connection in mobile networks: faster data connection in mobile networks: currently up to 384 kbps.. In future currently up to 384 kbps.. In future generations of WCDMA technology, this generations of WCDMA technology, this may increase up to even 10 Mbps. may increase up to even 10 Mbps.
You can do all of the usual activities: send You can do all of the usual activities: send SMS or MMS messages, download games SMS or MMS messages, download games and ringing tones, synchronize your phone and ringing tones, synchronize your phone with your PC calendar or corporate with your PC calendar or corporate intranet, and browse the Internet. intranet, and browse the Internet.
Mobile Broadband WCDMAMobile Broadband WCDMA
WCDMA is also fast enough for video WCDMA is also fast enough for video streaming. With GPRS or EDGE phones, you streaming. With GPRS or EDGE phones, you can't do these things while talking. WCDMA can't do these things while talking. WCDMA is based on a different technology that lets is based on a different technology that lets you hold simultaneous voice and data you hold simultaneous voice and data connections, so you can send images and connections, so you can send images and check your email while you're on the phone. check your email while you're on the phone.
Like GPRS and EDGE, you're billed for data Like GPRS and EDGE, you're billed for data transferred, not for time connected, so you transferred, not for time connected, so you can be connected just about all the time. can be connected just about all the time.
WCDMA
Information – DataAudio / Video on DemandInfotainment / EducationTV & Radio distribution
TelecommunicationPerson-to-Person Audio/Video, Fax (ISDN)Mobility-RoamingMailbox/Call Centre Services (SMS, Voice)Intelligent Network (IN)
Internet / IntranetE-MailWWWVoIPE-Commerce
UMTS Services
UMTS Based on WCDMA springs from convergence between the “World of Communication”
and “Information Technology”
Rich mobile services drive demand Rich mobile services drive demand for bandwidthfor bandwidth
Application sectors Application sectors considered in the considered in the
CalculationsCalculations The UMTS comprises a wide area of The UMTS comprises a wide area of applications, which are converted into six applications, which are converted into six main service classes for this analysis. These main service classes for this analysis. These are as follows:are as follows:
Speech Speech (S)(S) Simple Messaging Simple Messaging (SM)(SM) Switched Data Switched Data (SD)(SD) Medium Multimedia (Medium Multimedia (MMMMMM)) High Multimedia High Multimedia (HMM) (HMM) High Interactive MultimediaHigh Interactive Multimedia (HIMM): (HIMM):
Application sectors Service Application sectors Service Classes.Classes. (Cont’d)(Cont’d)
Speech (S)Speech (S)-Simple one to one or one to many voice -Simple one to one or one to many voice -Teleconferencing services -Teleconferencing services -Voicemail-Voicemail
Simple MessagingSimple Messaging (SM)(SM)--SMS and pagingSMS and paging-E-mail delivery-E-mail delivery-Broadcast and public information-Broadcast and public information
Switched Data (SD)Switched Data (SD)
-Low speed dial-up LAN access-Low speed dial-up LAN access-Low speed Internet/Intranet Access-Low speed Internet/Intranet Access-Fax-Fax
Application sectors Service Application sectors Service Classes. Classes. (Cont’d)(Cont’d)
Medium MultimediaMedium Multimedia (MMM)(MMM) -packet switched services which is require ‘busty’ -packet switched services which is require ‘busty’ in nature, data rates 0.5 Mbytes.in nature, data rates 0.5 Mbytes.
-Medium LAN and Internet/Intranet Access.-Medium LAN and Internet/Intranet Access.-Banking services-Banking services
High MultimediaHigh Multimedia (HMM)(HMM)-Packet switched services which is require ‘busty’ in -Packet switched services which is require ‘busty’ in nature, high bit rates of 10 Mbytes.nature, high bit rates of 10 Mbytes.-Fast LAN and Internet/Intranet Access-Fast LAN and Internet/Intranet Access-Video clips on demand-Video clips on demand-Audio clips on demand-Audio clips on demand-Online shopping-Online shopping
Application sectors Service Application sectors Service Classes. Classes. (Cont’d)(Cont’d)
High Interactive Multimedia (HIMM):High Interactive Multimedia (HIMM): -high-speed data rates with a minimum delay-high-speed data rates with a minimum delay
-Video telephony and video conferencing -Video telephony and video conferencing
-Collaborative working and telepresence-Collaborative working and telepresence
-Lottery and betting services-Lottery and betting services
Note:Note:
The first three services are the logical extensions of The first three services are the logical extensions of second generation mobile market and the last three second generation mobile market and the last three are addressing are addressing
the new mobile multimedia market.the new mobile multimedia market.
UMTS Spectrum Calculation UMTS Spectrum Calculation RESULTS RESULTS
ServicesServicesYear - 2006Year - 2006 Year - 2011Year - 2011
UplinkUplink DownlinDownlinkk
TotalTotal UplinkUplink DownlinDownlinkk
TotalTotal
High Interactive MMHigh Interactive MM 17.317.3 17.317.3 3535 42.342.3 42.342.3 8585
High MMHigh MM 0.470.47 93.393.3 9494 1.071.07 214.8214.8 216216
Medium MMMedium MM 0.30.3 7.67.6 88 0.280.28 10.710.7 1111
Switched DataSwitched Data 7.17.1 7.17.1 1414 5.15.1 5.15.1 1010
Simple MessagingSimple Messaging 0.980.98 0.980.98 22 0.950.95 0.950.95 22
SpeechSpeech 106.8106.8 106.8106.8 214214 114.7114.7 114.7114.7 230230
Sum Sum (MHz)(MHz) 132.8132.8 233.1233.1 366366 164.4164.4 389389 554554
TOTALTOTAL = 366 MHz x 1.10 == 366 MHz x 1.10 =403 403 MHzMHz
= 554 MHz x 1.05 == 554 MHz x 1.05 = 582 582 MHzMHz