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Where are we?
3G Wireless Summary
Evolution to Seamless Networking
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US Universal coverage achieved early 1980’s
“Wireless” First Generation Analog Systems
Speech
2.5 Generation Systems
Low Speed Data
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CDMA
OFDM
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Channelization code: Separate xmissions
Scrambling code: separate different sources
from each other
Scrambling code
Table 2.1: First Generation Analog Cellular Systems
Standard
Region
System Country
IS-54 USA
GSM Europe
IS-95 USA
600/200
1000/125
600
5-Oct
80/5
250/10
3
8
13-40
1
8
12
None
CRC
CRC
slot 1
slot 2
Table 2.3: IS-95 Air Interface Parameters
Bandwidth
IS-95B: 115.2 Kbps
Downlink: Slow quality loop
Number of Rake fingers
(c,c)
c
(c,-c)
Fig 2.4: Beginning of the Channelization Code Tree
CDMA Example
Signal Bit value 0 mapped into –1; Bit 1 value mapped into +1 e.g., 1 0 0 0 => +1 -1 -1 -1
Consider two users x and y
Consider two orthogonal codes: 1 1 1 1 (for user x) and 1 -1 -1 1 (for user y)
At transmit, user x data becomes +x +x +x +x and y becomes +y -y -y +y
The received signal is +x+y +x-y +x-y +x+y
For decoding, same codes as for transmit are used for the two users respectively.
When code 1 1 1 1 is used, the result due to correlation is
(+x+y)+(+x-y)+(+x-y)+(+x+y) = 4x
When code 1 -1 -1 1 is used, the result due to correlation is
(+x+y)+(-x+y)+(-x+y)+(+x+y) = 4y
Hence the original signals are separated at the receiving end
channelization code
scrambling code
Multipath Radio Channels and Rake Reception
Fig 2.6: Multipath Propagation Leads to a Multipath Delay Profile [1]
Transmitted
symbol
finger #1
finger #2
finger #3
Fig 2.7: The Principle of maximal Ratio Combining Within the CDMA Rake Receiver [1]
Input signal
(from RF)
Fig 2.8: Block Diagram of the CDMA Rake Receiver [1]
Y
Y
correlator
Successor to Frequency Hopping and Direct Sequence CDMA
Capability to cancel multipath distortion in a spectrally efficient manner without requiring multiple local oscillators (802.11a and 802.16)
Based on use of IFFT and FFT
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Transition from Short Message Service (SMS)
Open Internet standards for messaging
Web Applications
Information portals
Wireless Markup Language (WML) with signals using Wireless Application Protocol (WAP)
Location Communications Services
Location Awareness Based
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CAMEL = IN + Service portability (incl mobility and roaming)
Virtual Private Network (VPN)
Prepaid, Usage Limitations, Advanced Routing Services
Virtual Home Environment (VHE)
Integration of array of services, content conversion to heterogeneous services, network user profile, location aware services
Take the claims with a grain of salt
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High
And IEEE 802.11a
Ref: Honkasalo et al, WCDMA and WLAN for 3G and Beyond, IEEE Wireless Communication, Apr 2002
3.5G
2.5G
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3G Cellular (WCDMA)
Frequency Division Duplex (FDD): Uplink and Downlink are separated in frequency – (“symmetric”)
Time Division Duplex (TDD): Uplink and Downlink are separated in time – allows “asymmetric” traffic (adjust time slots in uplink and downlink)
3G Cellular (CDMA2000)
Blue Tooth
2.4 GHz band
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The favored twin sister of CDMA2000
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Battery Life
# PDP Contexts per IP Address
QPSK; coherent detection; Rake receiver
Short and Long Spreading Codes
Multicall – several simultaneous CS calls with dedicated bearers of independent traffic and performance characteristics
Customized Application for Mobile network Enhanced Logic (CAMEL) Phase 3
A lot to gobble
Bearer Independent Core Network
Tandem Free Operation (TFO), Transcoder Free Operation (TrFO), and Out of Band Transcoder Control (OoBTC)
Low Chip Rate TDD Operation
Network Assisted Cell Change
NodeB Synchronization for TDD
IPv6 packet switched network supporting both real time and non-real time traffic
Session Initiated Protocol (SIP) replacing SS7
Home Subscriber Server (HSS)
Multimedia Message Service (MMS) environment
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Intra Domain Connection to Multiple CN Nodes (Iuflex)
IP Multimedia CN Subsystem (IMS)
“Guaranteed” End to End (E2E) QoS in the PS domain
Global Text Telephony
CAMEL Phase 4
Same spectrum by both voice and data
Up to 12 spreading codes for High Speed DSCH (HS-DSCH)
Fast link Adaptation
Transmission Time interval 2 ms
Hybrid Automatic Repeat reQuest (HARQ)
Automatic optimizations to Channel Quality Indicator (CQI)
QPSK and 16 QAM modulation at 3.84 Mhz symbol; spreading factor fixed to 16
Incremental Redundancy or chase combining (CH)
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L3
control
control
control
control
Logical
Channels
Transport
Channels
Logical Channels: Type of information transferred over the radio interface
Channels made by soft hats
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Open Loop Power Control
Closed Loop Power Control
Outer Loop Power Control
Equal Opportunity Administration (EOA)
Softer
Soft
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Dimensioning
Estimation of average interference power
Coverage end Outage probabilities
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Dynamic Negotiations of properties / Services of radio bearer
Thruput, transfer delay, data error rate
Authentications
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Network Assisted GPS
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Limitation to meet expectations of applications like multimedia, full motion video, wireless teleconferencing
Wider Bandwidth
Difficult to move and interoperate due to different standards hampering global mobility and service portability
Primarily Cellular (WAN) with distinct LANs’; need a new integrated network
Limitations in applying recent advances in spectrally more efficient modulation schemes
Need all all digital network to fully utilize IP and converged video and data
Incessant human desire to reach the sky
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Seamless Roaming
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Convergence of Wireline, Wireless, and IP worlds
And Now for Something Completely Different
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Signalling Interface
UTRAN
N_B
N_B
RNC
RNC
HLR
AuC
PCM
SS7
PSTN/ISDN
Iub
Iub
Iur
Internet/Intranet/ISP
Support flexible bandwidth upto 20 MHz, new transmission schemes, advanced multi-antenna technologies, and signaling optimization
Instantaneous peak DL 100 Mb/s and UP 50 Mb/S within 20 MHz spectrum
Control plane latency of < 100 ms (camped to active) and < 50 ms (dormant to active)
> 200 users per cell within 5 MHz spectrum
Spectrum flexibility from 1.25 MHz to 20 MHz
Eliminate “dedicated” channels; avoid macro diversity in DL
Migrate towards OFDM in DL and SC-FDMA in UL
Support voice services in the packet domain
Adaptive Modulation and Coding using Channel Quality Indicator (CQI) measurements
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Source: www.3gpp.org
Attribute
3G
4G
Converged data and VoIP
Hybrid – integration of Wireless Lan (WiFi), Blue Tooth, Wide Area
Frequency Band
Bandwidth
Concatenated Coding
IP tunnels
Intelligent Internet
Radio Router
Smart Antennas
Wireless IP <---> IP Wireless
Integrate different modes of wireless communications – indoor networks (e.g., wireless LANs and Bluetooth); cellular signals; radio and TV; satellite communications
100 Mb/se full mobility (wide area); 1 Gbit/s low mobility (local area)
IP-based communications systems for integrated voice, data, and video
IP RAN
Successor to “SS7”; replacement for TCP
Maintain several data streams within a single connection
Service Location Protocol (SLP)
The demise of SS7
Diameter
Integrated LAN card and Subscriber Identity Modules (SIMs)
HSS
Expand beyond the circle
Challenge Shannon’s fundamental law of data communications (BW, Sig/No)
Hardware Frequency Synthesis techniques esp. for Frequency Hop (FH) systems
Traffic characteristics management (burstiness, directionality)
Multi Carrier Modulation (MCM)
MC-CDMA; OFDM
Quadrature Phase-Shift Keying (QPSK); Multilevel Quadrature Amplitude Modulation (M-QAM); Fast Fourier Transform (FFT)
Add cyclic extension or guard band to data
Challenges of Inter Symbol Interference (ISI) and Peak to Average Ratio (PAVR)
No pain, no gain
Signal Processing and optimizations
Synchronous and asynchronous transmissions
Spectrum Pollution
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N Dimensional vector spaces
Smart / Intelligent Antennas
Switched beam Antennas; adaptive arrays
Coverage limitations due to high frequencies (> 5 GHz)
Manage Entropy
More Efficient and Sensitive Transreceiver Designs
Noise figure, gain, group delay, bandwidth, sensitivity, tunable filters, spurious rejection, power consumption
Frequency Reuse; linearity techniques
Dynamic Frequency selection and packet assignments
Multi band, wide band, and flexible radios
Error Correction Coding
A/D and D/A transformations
All IP Network
Tunneling and Firewalls
Media Gateways for handling packet switched traffic
Trasnscoders, echo cancellations, media conversions Planetary Interoperability
Integration across different topologies
+ IP
Very Smart User equipment; away from “network Centric” architecture
Access routers
Encryption Protocols; Security and “trust of information”
Different rates, error profiles, latencies, burstiness
Dynamic optimization of scarce resources
Advanced Used interactions / presentation
Flexible displays
Web AI service / Interactive Intelligent Programs
Smart applications in the web; intelligent agents
Web Adaptiveness – global database schemes, global error corrective feedback, logic layer protocol, learning algorithms
Symbolic manipulation
Standardizations and Regulatory
Spectrum
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Next-Generation Internet (NGI)
Led by and focused on US Fed Agencies (DoD, DoE, NASA, NIH etc.)
High Performance networks: vBNS (NSF), NREN (NASA), DREN (DoD), ESnet (DoE),
Internet2
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Seamless Roaming, substantially high and selectable user bandwidth, customized QoS, Intelligent and responsive user interface
Mobile IP, Radio Routers, smart Antennas
Continued advances and challenges from 1G -> 4G
Modulation techniques, transreceiver advances, fast manipulations, user interfaces, IP tunelling and firewalls
Spectrum usage, regulatory decisions, “one” standard, authentication and security, multi disciplinary co-operation
Packing so much intelligence in smaller and smaller physical space, esp. User Equipment (UE)
IP + WPAN + WLAN + WMAN + WWAN + any other stragglers = 4G
IP in the sky with diamonds
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Uu
Iub
Iu-ps
SM
GMM
RRC
RLC
MAC-cd
PHY-up
FP
FP
PHY-up
MAC-cd
RLC
RRC
NBAP
ALCAP
ALCAP
NBAP
AAL2
SSSAR
AAL2
SSSAR
SAAL
SAAL
SAAL
SAAL
AAL5
AAL5
AAL5
AAL5
ATM
ATM
PHY
PHY
PHY
CDMA
PHY
CDMA
UE/MTE
IP
RLC
PDCP
MAC
PHY-up
FP
ALCAP
PHY-up
MAC
RLC
PDCP
AAL2
SAAL
AAL2
SAAL
FP
ALCAP
ATM
ATM
PHY
PHY
PHY
CDMA
PHY
CDMA
UE/MTE
IEEE 802.15: Wireless PAN (Bluetooth)
IEEE 802.16d and e: Wireless MAN (WiMAX)
IS-41: Inter-systems operation (TIA/EIA-41)
IS-54: 1st Gen (US) TDMA; 6 users per 30 KHz channel
IS-88: CDMA
IS-95: TIA for CDMA (US) (Cdmaone)
IS-124: Call detail and billing record
IS-136: 2nd Genr TDMA (TDMA control channel)
IS-637: CDMA Short Message Service (SMS)
IS-756: TIA for Wireless Network Portability (WNP)
IS-2000: cdma2000 air interface (follow on to TIA/EIA 95-B)
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ANSI:American National Standards Institute
BRAN:Broadband Radio Access Network (HYPERLAN 2) 2.5 Mbps
CAMEL:Customized Application for Mobile Enhanced Logic
CDMA:Code Division Multiple Access
ECMA:European Computer Manufacturers Association
ETSI:European Telecommunications Standards Institute
GTP:GPRS Tunneling Protocol
HLR:Home Location Register
IMSI:International Mobile Subscriber Identity
PDN:Public Data Network
VoIP:Voice over Internet Protocol
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2. WCDMA for UMTS, Ed.: H. Holma and A. Toskala, John Wiley, 2001
3. UMTS - Mobile Communications for the Future, Ed. F.Muratore, John Wiley, 2001
4. WCDMA: Towards IP Mobility and Mobile Internet, Eds E.Djanpera and R.Prasad, Artech House, 2001
5. IS-95 CDMA and CDMA2000, V.K.Garg, Publishing House of Electronics Industry, Beijing, 2002
6. IP Telephony, O. Hersent, D. Gurle Et, and J-P Petit, Addison-Wesley, 2000
7. www.mobileinfo.com
Adjacent cell sites use diffferent time offset
code for spreading
Complex soft Hand Over
Simple Soft Hand Over
Preudo Random (PN) sequence of length
of 10 ms
site offset of 64 chips
OVSF Codes
Walsh Codes
Standard
Region
Frequency
(MHz)
Channel
Spacing
(kHz)
finger #1
finger #2
finger #3
RNC
Y
Y
Y
Y
NodeB1
NodeB2
both NodeB's to UE, except for the
power control commands
Power control commands
to the UEs