Transcript LIDO Digital Cellular Networks - School of Information Technology

LIDO Telecommunications Essentials®
Part 4
Wireless Communications
Wireless Wide Area Networks
1
Freedom and Mobility
• Given the basic human desire and need for
freedom of movement, it is little surprise that the
demand for wireless network solutions is enormous.
• With the introduction of cellular communications, we
saw an increasing demand for wireless services.
• The growth was so rapid that by 2002, we
witnessed a major shift in network usage: For the
first time in the history of telecommunications, the
number of mobile subscribers exceeded the
number of fixed lines.
• Industry predictions are that there will be 3.96 billion
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LIDO mobile subscribers worldwide by 2011.
Cellular Evolution
1G and 2G
• First generation (1G) – 1979 - Analog
– Standards include AMPS, TACS, JTACS, and NMT.
• Second generation (2) – 1992 - Digital
– Key standards - GSM, UWC-136, cdmaOne, and
PDC.
– PCS standards include GSM 1800, GSM 1900, and
PDH.
– 2.5G offers enhancd data services on existing 2G
digital platforms.
– 2.5G standards include GPRS, High-speed Circuit
Switched Data (HSCSD), and EDGE.
3
LIDO
Cellular Evolution
3G
• Third generation (3G) – 2002 – digital - mobile
– broadband (voice, data, multimedia)
– high-speed data (144 Kbps/384 Kbps/2 Mbps)
– 3G standards include W-CDMA, UMTS,
CDMA2000, CDMA450, TD-SCDMA, and FOMA.
– 3.5G, introduces enhancements designed for
services running over an IP backbone, including
high-speed data and video.
– 3.5G standards include HSDPA, HSUPA, and
HSOPA.
– Beyond 3G is an enhancement to 3G Beyond 3G
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is also known as Super 3G and Ultra 3G.
LIDO
Cellular Evolution
4G
• Fourth generation (4G) - beyond 2008
– Will provide a huge expansion in mobile
broadband capacity and bandwidth.
– Promises a maximum of 50Mbps to
100Mbps while moving.
– Promises to provide an average of 20Mbps
up to 1Gbps while standing still.
– Key technologies for 4G are OFDM and
MIMO.
LIDO
5
Cellular Evolution
5G
• Fifth generation (5G) – beyond 2010
– 5G will enable fast downloads of large
chunks of data across the Internet.
– 5G will support advanced multimedia
applications such as
• teleimmersion
• virtual reality
• telerobotics
LIDO
6
Analog Cellular Systems
• Advanced Mobile Phone System (AMPS)
– 800 MHz, 832 Channels/carrier
– Origin: United States
• Total Access Communications System (TACS)
– 900 MHz, 1,000 Channels
– Origin: United Kingdom
• Japanese Total Access Communications System (JTACS)
– 800-900 MHz
– Origin: Japan
• Nordic Mobile Telephone System (NMT)
– 450 MHz, 220 channels
– 900 MHz
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LIDO
Analog Cellular Radio System
M
T
S
O
= Base transceiver station (BTS)
MTSO
= Mobile telephone switching office
Local exchange
Telephone Land Line
Microwave
or Wireline
= Mobile unit (mobile station)
= Wireline
LIDO
8
Cellular Digital Packet Data
(CDPD)
• CDPD is a digital transmission system that is
deployed as an enhancement to the existing
cellular network.
• Initially introduced in 1992.
• CDPD is a packet data protocol designed to
work over AMPS (the original cellular
network), or as a protocol for the TDMA (time
division multiple access) air interface.
• The main objective was to make use of
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LIDO unused bandwidth.
CDPD Characteristics
• A connectionless, multiprotocol network service,
CDPD is designed to operate as an extension of
existing data networks, namely IP.
• Complete network specification, including
architecture, airlink, network interfaces, encryption,
authentication, network management, and security
• Throughput is nominally 19.2 Kbps; expect 9.6
Kbps
• Requires a special subscriber unit
• Applications include public safety, point of sale,
mobile positioning and other business services.
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LIDO
CDPD Network
Circuit Cellular
Antenna
Laptop
Cellular
Modem
Cellular
Phone
CDPD
traffic
CDPD Mobile
Data Base
Station
CDPD
LIDO
Laptop with CDPD
subscriber device
Cellular
Data
Cellular
telephone
base station
CDPD Mobile
Data Intermediate
System (router)
Switched
Telco network
CDPD
Router
network
User
site
User
site
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Packet Radio Data Networks
• Packet radio data networks utilize licensed
bandwidth and are built specifically for twoway data.
• The data rates supported by packet radio
range up to 19.2Kbps, but the norm is
9600bps.
• The key applications for packet radio include
dispatching, order processing, airline
reservations, financial services and banking,
lottery, remote database access, messaging,
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LIDO point-of-sale, and telemetry.
Packet Radio Data Network
Diagram
User
site
Public data
network
Laptop
Packet modem
Host
Private packet
base station
LIDO
Private
Packet
networ
k
User
site
13
Mobitex
• Mobitex is a paging network developed by Ericsson.
It is an open standard for dedicated wireless data
and emphasizes reliability and its use in safety-type
applications.
• Mobitex is a trunked radio system based on X.25
• Data rate up to 19.2 Kbps, generally 9.6 Kbps
• It is a packet-switched, narrowband, data-only
technology mainly for short-burst data.
• Key applications include such as interactive
messaging, e-mail, machine-to-machine,
telematics, positioning, and forms-based
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LIDO applications.
Mobitex
• Mobitex channels are 12.5KHz wide.
• Uses licensed bandwidth - currently Mobitex is
available on the 80MHz, 160MHz, 400MHz,
800MHz and 900MHz frequency bands.
• Mobitex is offered on more than 30 networks on five
continents.
• Mobitex is also being used in combination with
GPRS, WLAN (802.11), satellite, and CDMA.
• There are also several Bluetooth-enabled products
and applications for Mobitex.
LIDO
15
Digital Cellular Networks
• The growing demand for mobile
communications required the digitalization of
the cellular infrastructure.
• The introduction of digital cellular technology
allowed for many improvements, including
– Increased capacity
– Improved spectrum utilization
– Improved security
– Roaming capability
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LIDO
Digital Cellular Architecture
Gateway
MSC
(GMSC)
BSC
PSTN
VLR
MSC
HLR
BSC
AUC
EIR
= Base transceiver station (BTS)
Base station controller (BSC)
Mobile Switching Center (MSC)
LIDO
VLR Visitor Location Register
HLR Home Location Register
AUC Authentication Center
EIR Equipment Identity Register
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Digital Cellular Databases
• A number of databases are critical to the process of
roaming.
• The HLR provides information about the
subscribers.
• The VLR stores information about the calls being
made by roaming subscribers.
• The AC protects the subscriber, and therefore the
carrier.
• The EIR registers the mobile equipment types and
maintains a database of equipment that has been
stolen
or
blacklisted
for
some
reason.
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LIDO
Cellular vs PCS
CELLULAR
Analog/Digital
800-900 MHz
Macrocell (up to 8 miles)
High power (.6 - 3W)
LIDO
PCS
Digital
1800-2000 MHz
Micro/Picocell (+/- 1 mile)
Low power (100mW)
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Global System for Mobile
Communications (GSM)
• Global System for Mobile Communications (GSM),
introduced in 1992, is the most popular 2G
standard.
• GSM is the technology that underpins most of the
world's mobile phone networks.
• Today, GSM technology is used by more than 29%
of the world's population and represents almost
82% of the world's cellular market.
• There are over to 1,700 models of GSM phones
available from more than 100 vendors.
LIDO
20
GSM Frequency Bands
• GSM utilizes TDMA and FDD.
• GSM currently operates in four frequency bands
– mobile stations transmit on the lower frequency
sub-band
– base stations transmit on the higher frequency subband
– GSM 850 - implemented in North America
– GSM 900 - traditional implementation
– GSM1800 – global PCS implementation
– GSM 1900 - North American PCS implementation
LIDO
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GSM Characteristics
• Tri-band and quad-band phones are now available,
enabling global roaming.
• Supports 124 200-KHz full duplex channels
– Divides each 200 KHz channel into eight time
slots, supporting 8 callers per channel
• Uses linear predictive coding (LPC) to encode
speech at 13 Kbps
• GSM supports both voice and data, but with basic
GSM, data rates reach only as high as 9600bps.
LIDO
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GSM Features
• GSM supports international roaming with a single
invoice.
• GSM supports Short Message Service (SMS).
• GSM supports Group III fax.
• A Subscriber Identity Module (SIM) card defines the
accounting, personal details, and phone number of
an individual's service.
• The SIM card can be used in any GSM handset to
activate service.
LIDO
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GSM Benefits
•
•
•
•
Improved spectrum utilization
Improved security due to digital system
Authentication and fraud prevention via smart cards
A variety of voice compression devices are being
developed to make more efficient use of the
available spectrum.
• The ability to create closed user groups and engage
in group calls is also being developed.
• GSM now offers a number of enhanced data
services known as 2.5G.
LIDO
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Universal Wireless Communications
(UWC)
• UWC was at one time the dominant technology in
North America and Latin America.
• Also known as ANSI-136 and TDMA
• Utilizes TDMA and TDD schemes.
• Offers a total of six time slots, carrying three
conversations per channel.
• Operates in the 800MHz frequency band
• Uses AMPS signaling to reserve resources,
transfers speech in digital form
• Digital overlay that is interoperable with AMPS
LIDO
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UWC Data Services
• IS-136 – up to 30 Kbps
• IS-136+ 43.2 Kbps - 64 Kbps
• IS-136HS - 384 Kbps - 2 Mbps
– 8 - PSK modulation
– GPRS for packet data
– Support for Edge
• UWC-136, an enhancement of IS-136, uses EDGE
technology and a wideband TDMA technique.
LIDO
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cdmaOne Characteristics
• CDMA is a method of transmitting simultaneous
signals over a shared portion of the spectrum.
• cdmaOne, based on the TIA/EIA IS-95 CDMA
standard, is a 2G technology that offers a data rate
range of 9.6Kbps to 14.4Kbps.
• cmdaOne relies on spread spectrum technology.
• cdmaOne operates in the 800MHz and 1900MHz
frequency bands but can work on other frequency
bands as well.
• cdmaOne utilizes FDD, with a 1.25MHz channel in
each direction.
LIDO
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IS-95 Standards
LIDO
• TIA/EIA IS-95 was .published in July 1993
• IS-95A, the initial data-friendly revision, was
published in May 1995.
• IS-95A describes the structure of the 1.25MHz
CDMA channels, power control, call processing,
handoffs, and registration techniques for system
operation.
• IS-95B allows for code or channel aggregation to
provide data rates of 64 Kbps to 115 Kbps.
• IS-95B also offers improvements in soft hand-offs
and interfrequency hard hand-offs.
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• IS-95B is categorized as a 2.5G technology.
IS-95 HDR Standards
• IS-95 HDR (for High Data Rate) provides a
spectrally efficient 2.4Mbps peak rate in a standard
1.25MHz channel bandwidth for fixed, portable, and
mobile applications.
• Based on standard IP, IS-95 HDR is optimized for
packet data services.
• IS-95 HDR supports e-mail, web browsing, mobile
e-commerce, telematics, and many other
applications while offering end users continuous,
untethered, always-on access to the Internet and
next-generation data services.
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LIDO • IS-95 HDR is categorized as a 3G technology.
cdmaOne Benefits
• cdmaOne offers numerous benefits to cellular
operators and their subscribers
– capacity increases
– improved call quality
– simplified system planning
– enhanced privacy
– improved coverage characteristics
– increased talk time for portables
– bandwidth on demand
LIDO
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2.5G GSM Developments
• Enhanced data services
– General packet radio services (GPRS)
– High-speed circuit switched data (HSCSD)
– Enhanced Data rates for Global Evolution
(EDGE)
• Currently more than 80 items covered in the
working areas
LIDO
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High-speed circuit-switched data
(HSCSD)
• An enhancement to GSM, HSCSD uses
existing circuit-switched equipment with
software upgrades.
• HSCSD enables greater data rates by
grabbing several time slots for a single user
• HSCSD supports data rates from 9.6 Kbps
up to 64 Kbps with timeslot aggregation.
• With channel aggregation, up to 100 Kbps
can be achieved.
LIDO
32
HSCSD
• HSCSD provides for several levels of error
correction, supporting between 9.6 Kbps to
14.4 Kbps per time slot.
• A maximum data transfer rate of up to
57.6Kbps can be achieved by using multiple
time slots.
• The GSM network is configured such that
normal voice calls take precedence over
additional time slots for HSCSD users.
• In order to maintain the user connection, the
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LIDO user will be charged at a higher rate.
HSCSD
• Key HSCSD applications include
• large file transfers
• remote access
• videoconferencing
• multimedia transmission
• HSCSD is offered to subscribers using either voice
terminals that support the feature or a special PC
card with a built-in GSM phone.
• International Roaming agreements between all
HSCSD Operators have been implemented.
LIDO
34
General Packet Radio Services
(GPRS)
• General Packet Radio Services, or GPRS, is an
enhancement to the GSM system that supports
data packets.
• GPRS is IP-based connectivity that supports a wide
range of enterprise and consumer applications.
• GPRS provides users with throughput rates of up to
40Kbps.
• For operators, the adoption of GPRS is a fast and
cost-effective strategy.
• GPRS has been integrated into GSM standards
releases since Release 97.
LIDO
35
GPRS
• GPRS is a packet-switched solution that works by
overlaying a packet-based air interface on the eight
time slots used for GSM transmissions.
• GPRS is always-on service, enabling continuous
flows of IP data packets and supporting applications
such as web browsing and file transfer.
• Offers transmission speeds, theoretically, of up to
172.2 Kbps
• In practice, the actual speeds experienced are
substantially lower than this.
LIDO
36
GPRS Network
MSC/VLR
GSM Network
HLR/Auc/EIR
BSC
PSTN
SS7
PCU
Charging
Gateway
BTS
SGSN
Billing
Center
GGSN
GPRS
Backbone
Firewall
GGSN
Firewall
GGSN
Internet,
IP Backbone
IP Backbone
LIDO
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GPRS Components
GPRS Network
Internet
GGSN
Gateway
Node
SGSN
Serving
Node
Base Station
•GPRS does not require a new infrastructure
•GPRS allows you to add packet-based data service to the
existing network with minimal changes – add GGSN and SGSN
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LIDO •GPRS does not require a new frequency allocation
GPRS Applications
• Key GPRS applications include
– corporate e-mail, Internet e-mail
– job dispatch
– remote LAN access
– file transfers
– web browsing
– still image transfer
• GPRS is largely a tool for a variety of less complex
data sessions.
• The GSMA has established a technical GPRS
roaming platform that it calls Roamfest.
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LIDO
Enhanced Data Rates for Global
Evolution (EDGE)
• EDGE builds on enhancements provided by GPRS
and HSCSD technologies.
• EDGE allows operators to
– handle three times more subscribers than with
GPRS
– triple their data rate per subscriber
– or add extra capacity to their voice
communications
• Because EDGE uses the same TDMA frame
structure, logic channel, and 200KHz carrier
bandwidth as today's GSM networks, it to be
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LIDO overlaid directly onto an existing GSM network.
EDGE Applications
• EDGE allows the delivery of advanced mobile
services
– downloading of video and music clips
– multimedia messaging
– high-speed color Internet access
– e-mail on the move
• Virtually all new GSM infrastructure
deployments are also EDGE capable.
LIDO
41
The EDGE Advantage
• EDGE enables a greater data transmission speed
to be achieved in good conditions, especially near
the base stations.
• GSM relies on Guassian Minimum Shift Keying
(GMSK) which encodes 1 bit per cycle (or Hertz).
• EDGE utilizes 8-PSK modulation which enables
each pulse to carry 3 bits of information.
• 8-PSK increases the data rate of existing GSM
systems by a factor of three.
LIDO
42
EDGE Components
BSC
MSC
Local
exchange
PSTN
PCU
BTS
BTS
SGSN
BTS
GGSN
Internet,
IP Backbones
BSC
PCU
BTS
SGSN
BTS
BTS
LIDO
43
EDGE Characteristics
• Combines digital TDMA and GSM.
• Provides an enhanced version of GPRS.
• Supports 48-69.2 Kbps per timeslot, and up
to 384 Kbps with timeslot aggregation.
• Maintains GSM's 200KHz channel spacing,
allowing the use of existing spectrum bands.
• EDGE is also sometimes referred to as a
2.75G system.
LIDO
44
GSM Edge Radio Access Network
(GERAN)
• GERAN is a Phase II of EDGE.
• Supports data rates of up to 1,920Kbps.
• Supports packetized voice and real-time
services.
• Interfaces to an all-IP 3G core network.
• Provides a cost-efficient means to deliver 3G
services within the existing frequency bands.
LIDO
45
Short Message Service (SMS)
• SMS provides a mechanism for transmitting short
messages to and from wireless devices, acting as a
store-and-forward system for short messages.
• SMS supports text messages, up to 160
alphanumeric characters in length.
• There are two successors to SMS
– Enhanced Messaging System (EMS)
– Multimedia Messaging System (MMS)
• Like SMS, both support person-to-person messaging
as well as the distribution of content to mobile
devices, however EMS and MMS offer more
sophisticated messaging and MMS does not limit the
46
LIDO message size to 160 characters.
Enhanced Messaging Service
• EMS enables the sending of a combination of
media types as a message to another EMScompatible phone.
• EMS supports three image formats:
– small, which is 16 x 16 pixels
– large, which is 32x 32 pixels
– and variable
• EMS also supports animated images in two formats:
– small, which is 8 x 8 pixels
– large, which is 16 x 16 pixels
• EMS phones used predefined animations that
47
LIDO represent various emotional states.
Multimedia Messaging Service
• MMS is designed to operate over both 2.5G and 3G
networks
• MMS makies use of new transmission methods
including GPRS, HSCSD, EDGE, and UMTS.
• MMS involves attaching multimedia extensions
such as video and sound to messages.
• MMS requires a new network infrastructure as well
as MMS-enabled handsets.
LIDO
48
Multimedia Messaging Service
• MMS supports
– standard image formats such as GIF and JPEG
– video formats such as MPEG-4
– audio formats such as MP3, MIDI, and WAV
• The dramatic shift toward the use of phones
equipped with cameras is creating a growing
market for MMS services.
LIDO
49
3G: Moving Towards Broadband
• Data, video and multimedia traffic is on the rise.
• The current wireless spectrum and compression
techniques do not properly support the wireless
Internet, or provide a platform for the delivery of
multimedia content and TV programming.
• The future demands a new generation of
infrastructure, and 3G is one step toward the
broadband wireless realm.
• 3G requires licensing of new spectrum, as well as
an entirely new infrastructure.
• While 3G is still under development, deployments
50
LIDO are growing, as are the number of subscribers.
3G: Moving Towards Broadband
• Although we are not yet able to experience all the
mobile broadband multimedia services and
maximum data rates promised by 3G, we are
seeing more deployments of 3G networks, and
enhanced 3G services are beginning to make an
appearance.
• 4G and 5G networks are already in development.
• At any point in time, new technologies are being
developed and operating in labs that will emerge
commercially within five to seven years.
LIDO
51
ITU IMT-2000 Framework
Global
Suburban
Urban
In-Building
Satellite
Macrocell
Microcell
Picocell
LIDO
52
The Third Generation of Wireless
• 3G is designed for high-speed multimedia data and
voice, including high-quality audio and video and
advanced global roaming.
• 3G is defined by the ITU under the IMT-2000.
• IMT-2000 goals include
– Equivalency between wireline and wireless
– Support for messaging, Internet access, high-speed
multimedia
– Improved throughput
– QoS support
– Improved security
– Improved voice quality
LIDO
53
3G Spectrum Allocation
• In 1992, WARC (World Administrative Radio
Conference) allocated 1885-2025 MHz and 21102200 MHz for IMT 2000, including 1980-2010 and
2170-2200 MHz for satellite.
• In 2000, WARC allocated additional spectrum in
three frequency bands:
– One below 1 GHz
– One at 1.7 GHz (where many 2G systems
currently operate)
– One in the 2.5 GHz range
• WARC is now referred to as the World
54
LIDO Radiocommunications Conference.
IMT-2000 Core Frequency Bands
• Terrestrial IMT-2000 services operate in the FDD
mode in the bands 1920 - 1980 MHz paired with
2110 - 2170 MHz.
– Mobile stations transmit in the lower sub-band
– Base stations transmit in the upper sub-band
• The bands 1885 - 1920 MHz and 2010 - 2025 MHz
are unpaired for TDD operation.
• The GSMA feels that several additional frequency
bands should be non-exclusively designated for the
use of IMT-2000 to provide for up to an additional
160MHz of spectrum.
– These bands include 698MHz–806MHz, 2500MHz–
2690MHz, and 2700MHz–2900MHz.
LIDO
55
Mobile Satellite Service
• 3G also includes a satellite component, known as
Mobile Satellite Service (MSS), intended to take
over when a user is out of range of terrestrial base
stations.
• The target data rate for MSS is 100Kbps, compared
to 2Mbps for terrestrial systems.
• MSS operators hope to offer services similar to
those of terrestrial 2.5G and 3G networks, including
data at ISDN speeds, toll-quality voice, video, and
multimedia messaging.
LIDO
56
3G Basic Applications
• Basic 3G applications include
– High quality voice transmission
– Global roaming
– 144 Kbps - 2 Mbps for packet and circuit
data
– Always-on data availability
– High-speed mobile Internet access
– High-capacity email (send and receive)
LIDO
57
3G Broadband Applications
• 3G broadband applications include
LIDO
– Videoconferencing
– Navigation/mapping systems
– Streaming video and TV
– Common billing/user profiles
– Multimedia messaging
– Mobile voice and video over IP
– Calling line image
– Mobile entertainment
– M-commerce payment solutions
– Location-based services
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3G Standards
• The ITU started the process of defining the
standard for 3G systems with IMT-2000.
• The European Telecommunications Standards
Institute (or ETSI) was responsible for the UMTS
standardization process in Europe.
• The 3G Partnership Project (3GPP) was formed in
1998, under the ETSI.
• 3GPP specifications are based on the UMTS
system.
• 3GPP has five main UMTS standardization areas:
radio access network, core network, terminals,
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LIDO services and system aspects, and GERAN.
3GPP Standards
• 3GPP standards are structured as releases.
• Current 3GPP releases include the following:
LIDO
– Release 98 specifies pre-3G GSM networks
– Release 99 specifies the first UMTS 3G networks,
incorporating a CDMA air interface
– Release 4, which was originally called Release 2000,
adds features including an all-IP core network
– Release 5 introduces IMS and HSDPA
– Release 6 integrates operation with WLAN networks and
adds HSUPA
– Release 7 focuses on better integration with wired
networks and examines advanced receivers
60
3GPP2 Standards
• The 3G Partnership Project 2 (3GPP2) was formed
when ETSI refused to expand the scope of 3GPP to
address cdma2000.
• The American National Standards Institute (ANSI)
formed 3GPP2 to coordinate cdma2000
developments.
• The work of producing 3GPP2's specifications
resides in the project's four technical specification
groups (TSGs).
–
–
–
LIDO –
TSG-A covers access network interfaces
TSG-C covers cdma2000 standards
TSG-S covers services and systems aspects
TSG-X deals with core networks
61
3G Radio Interfaces
Interface
Technology
Technique
W-CDMA
(UMTS, UTRA
FDD)
CDMA
CDMA2000 (1X
and 3X)
CDMA
Direct
Sequence
Multicarrier
UTRA TDD and
TD-SCDMA
CDMA
Time code
UWC-136/EDGE
TDMA
Single-carrier IMT SC
DECT
FDMA/TDMA
Frequency
Time
LIDO
ITU
Designation
IMT DS
IMT MC
IMT TC
IMT FT
62
UMTS/W-CDMA
• Universal Mobile Telecommunications System
(UMTS), the European implementation of the 3G
wireless phone system, utilizes W-CDMA.
• Driven by the need to provide broadband and other
packet services to users at home, at work, or on the
road.
• UMTS defines both narrowband and broadband
services.
– Narrowband is defined as 2Mbps in the 2GHz band
– Broadband is defined as100Mbps+ in the 60GHz band.
• Personal mobility is a major objective of UMTS.
LIDO
63
UMTS/W-CDMA Standard
• Frequency band:1920 MHz -1980 MHz and 2110
MHz - 2170 MHz (Frequency Division Duplex)
• Minimum frequency band required: ~ 2x5MHz
• Frequency re-use: N=1
• Modulation: QPSK
• Circuit and Packet based services
• Maximum user data rate offered: 384 kbps , also
higher rates ( ~ 2 Mbps) promised.
• HSPDA upgrade will offer data speeds up 10 Mbps,
and 20 Mbps with MIMO systems.
LIDO
64
3G Evolution
1992-2000
2000-2004
2004-2009 2002-3 to 144 Kbps
2003-4 to 384 Kbps
2005-6 to 4 Mbps
2007-9 to 7 Mbps
2010+ to 100 Mbps
GPRS/EDGE
GSM
GPRS
W-CDMA
(R99)
HSDPA
(R5)
HSUPA
(R6)
HSOPA
(R7)
VoIP
LIDO
65
HSDPA
• High Speed Downlink Packet Access provides
improvements in the downlink channel.
• HSDPA is part of the 3GPP/UTRAN FDD Release 5
W-CDMA specifications.
• HSDPA evolved from and is backward compatible
with Release 99 W-CDMA systems.
• Release 5 specifications provide
– data rates from 8Mbps to 14Mbps over a 5 MHz
channel
– 20Mbps when MIMO systems are used
LIDO – support for packet-based multimedia services 66
HSPDA Modulation Methods
• HSDPA utilizes QPSK modulation for noisy
channels
– QPSK can tolerate higher levels of interference
but has a lower transmission bit rate
• HSDPA utilizes 16-QAM modulation for
clearer channels
– 16-QAM offers twice the bit rate but is more
prone to errors
– Techniques like 16-QAM require stronger forward
error correction (FEC)
LIDO
67
HSDPA Benefits
• HSDPA delivers a four- or five-fold increase in
downlink data speeds .
• HSDPA attributes include
– Shortened round-trip time between network and
terminals
– Reduced variance in downlink transmission delay
• Theoretical peak rate is 14.4Mbps
– realistic experience is currently closer to 1.8Mbps
to 3.6Mbps
LIDO
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HSDPA Features
• HSDPA is a packet-based data service in the
WCDMA downlink channel.
• HSDPA was designed to support IP and packetbased multimedia services.
• HSDPA offers many service-enhancing features,
including Adaptive Modulation and Coding (AMC).
• HSDPA can utilize MIMO, greatly improving
capacity.
– MIMO antenna systems support data
transmission rates up to 20Mbps.
LIDO
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HSDPA Error Control
• HSDPA utilizes Hybrid Automatic Request (HARQ)
which greatly improves error control.
– HARQ is a variation of the ARQ error control
method.
– With ARQ, the receiver detects transmission
errors in a message and automatically requests a
retransmission from the transmitter.
• HARQ combines FEC and ARQ by encoding the
data block plus error-detection information with an
error-correction code prior to transmission.
• Other features of HARQ include fast cell search and
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LIDO advanced receiver design.
HSDPA Operation
Data
Device 1
L1 Feedback
Base
Transceiver
Station
LIDO
Data
Device 2
L1 Feedback
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HSDPA vs WiMax
• HSDPA greatly improves the user applications
experience.
• HSDPA is often compared to WiMax.
• Early HSDPA will focus on data, voice, and mobility
from the handset perspective.
• WiMax will focus on broadband data, initially to
underserved areas because of its distance
capability.
• HSDPA requires no new infrastructure, just the
downloading of new software to the handset.
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LIDO• WiMax requires a new infrastructure.
HSUPA
• High Speed Uplink Packet Access provides
enhancements to the uplink data speed.
• HSUPA is being standardized in the 3GPP Release
6 specification.
• HSUPA’s uplink Enhanced Dedicated Channel (EDCH) employs link adaptation methods similar to
those used by HSDPA, including
– shorter transmission time interval (TTI), enabling
faster link adaptation
– HARQ with incremental redundancy, making
retransmission more effective.
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LIDO • The link adaptation process is dynamic.
HSUPA
• HSUPA standard supports upstream data
transmission rates up to 5.8Mbps.
• Some consider HSUPA to be a 3.75G technology.
• Jointly, downlink and uplink enhancements are
referred to as High-Speed Packet Access (HSPA)
services.
• Increased downlink and uplink speeds will
– Enhance user experiences
– Increase the use of applications
– Increase use of activities where data is shared
between users
LIDO
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HSOPA
• While HSDPA and HSUPA are being deployed,
the next step is being standardized, a
technique called High-Speed OFDM Packet
Access. (HSOPA)
• By using OFDM and MIMO, HSOPA promises
to support up to 40Mbps download speed.
• HSOPA is expected to dramatically reduce
costs due to the spectral efficiency of OFDM.
• HSOPA moves forward in the standards
procedure, it is expected to make its
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LIDO commercial debut in 2008.
UMTS TDD
• UMTS Time Division Duplex (TDD) is
specifically intended for high-data-rate
services.
• UMTS TDD uses TDD and is designed to
work in a single, unpaired frequency band.
• UMTS TDD uses a combined TDD and
CDMA scheme.
• It was first defined by the 3GPP in Release
99, and it has continued to evolve in the later
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LIDO releases.
UMTS TDD / TD-CDMA Standard
• Frequency band:1900 MHz -1920 MHz and 2010
MHz - 2025 MHz (Time Division Duplex) Unpaired
• Duplex technique: TDD
• UMTS TDD can also operate in other licensed
spectrum bands, including 3.6GHz.
• Direct Sequence Spread Spectrum (DSSS)
• Modulation: QPSK
• Operates on a single 5MHz or 10MHz channel.
20 MHZ channels are planned as well.
• Frequency reuse: N=1
• Peak download speeds up to 12 Mbps.
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LIDO
UMTS TDD / TD-CDMA Benefits
• TDD supports variable asymmetry.
– Allows an operator to command how much capacity
is allocated to downlink versus uplink.
– The result is better use of spectrum and higher
efficiency.
• UMTS TDD supports mobility.
– Claims to allow subscribers to stay connected while
traveling in excess of 120 km/hr while within the
network footprint
• UMTS TDD supports tower-to-tower handoff, and
network-to-network roaming.
• TD-CDMA devices consume less power.
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LIDO
TD-SCDMA
• Time Division Synchronous CDMA (TD-SCDMA)
was proposed by China Wireless
Telecommunication Standards group (CWTS) and
approved by the ITU in 1999.
• Technology is being developed by the Chinese
Academy of Telecommunications Technology and
Siemens.
• TD-SCDMA is primarily aimed at the mainland
Chinese market and in support of voice services.
LIDO
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TD-SCDMA Features
• TD-SCDMA uses TDD, significantly improving
network performance.
– It transmits uplink traffic and downlink traffic in the
same frame in different time slots.
– Uplink and downlink resources are assigned
according to the individual user needs.
• TD-SCDMA supports both synchronous circuitswitched services and asynchronous packetswitched services.
• Data rates can range from 1.2Kbps to 2Mbps.
• TD-SCDMA also supports highly efficient spectrum
usage by using CDMA.
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LIDO
TD-SCDMA
• TD-SCDMA covers all application scenarios, being
designed to address all cell sizes
–
–
–
–
Metropolitan city centers
Indoor and campus environments
Hot spots
Rural areas
• TD-SCDMA offers optimum efficiency for both
symmetric and asymmetric data services.
• A minimum frequency band of 1.6 MHz allows for
flexible allocation of the spectrum.
• Seamless hand-over between TD-SCDMA and
LIDO GSM guarantees that no call is lost while moving. 81
TD-SCDMA Standard
• Frequency band: 2010 MHz - 2025 MHz in China
(WLL 1900 MHz - 1920 MHz)
• Can operate in a minimum frequency band of
1.6 MHz for 2 Mbps, or a 5MHz band for 6 Mbps
• Frequency reuse: N=1 or N=3
• Duplex technique: TDD
• Modulation: QPSK or 8-PSK
• Voice data rate: 8kbit/s
LIDO
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CDMA2000
• With existing networks nearing saturation and
demand for wireless services continuing to grow,
operators have been looking at technologies that
will deliver increased capacity at the lowest possible
cost.
• In fact, one of the biggest drivers behind 3G is
capacity improvement, and network capacity is one
of the key criteria for 3G technology selection.
• CDMA2000 was the first 3G technology to be
commercially deployed as part of the ITU's IMT83
LIDO 2000 framework.
CDMA2000 Network Diagram
HLR/AUC
Mobile Phones
PSTN
MSC
AAA Server
Smart Phones
& PDAs
Core Elements
BSC
IWF
Lap Tops with
Mobile Phones
Internet
IP Router
LIDO
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CDMA Benefits
• cdmaOne and CDMA2000 are the most spectrally
efficient technologies and support at least twice the
maximum number of voice calls as current nonCDMA 2G technologies.
• cdmaOne delivers the most capacity in the 2G
world, even considering the latest frequencyhopping techniques and adaptive multirate voice
codecs in GSM networks.
• CDMA2000, which is now being deployed
worldwide, doubles the capacity of cdmaOne
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LIDO networks.
IS-95 HDR
• IS-95 High Data Rate (HDR) is being used as the
underlying technology for cdma2000.
• IS-95 HDR is optimized for IP packets and Internet
access, and it can be used to enhance data
capabilities in existing cdmaOne networks.
• With existing CDMA networks, a number of
channels are changed from voice to data.
• Using a combination of TDM and CDMA, IS-95
HDR shares each channel among several users on
an as-needed basis.
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LIDO
IS-95 HDR
• cdma2000 promises a 2.4Mbps peak data
rate in a standard 1.25MHz CDMA voice
channel.
• The IS-95 HDR data rate varies, depending
on the distance between the mobile phone
and the base station.
• As more GSM operators convert to 3G WCDMA technology and implement HSDPA,
HSDPA could dwarf cdma2000.
LIDO
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CDMA2000 1X RTT
• CDMA2000 represents an entire family of
technologies.
• CDMA2000 1X RTT (or Radio Transmission
Technology)
– doubles the voice capacity of cdmaOne networks
– delivers peak rate packet data speeds of 153Kbps
downstream (with Release 0) and 307Kbps
downstream (with Release 1) in mobile environments
– utilizes a single 1.25MHz carrier in new or existing
spectrum
• Enabled services include entertainment, e-mail and
picture transfer, and location, traffic and GPS
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LIDO services.
CDMA2000 1XEV-DO
• CDMA2000 1xEV-DO (Enhanced Version–Data
Only) uses a separate 1.25MHz carrier for data,
providing data-optimized channels.
• Asymmetric - it supports up to 2.4Mbps
downstream and up to 153Kbps upstream.
– The average rate is between 300Kbps and 600Kbps
• 1xEV-DO Revision A
– Supports IP packets
– Increases the downlink peak rate to 3.1Mbps
– Increases the uplink rate to 1.2Mbps.
LIDO
89
CDMA2000 1XEV-DO
• 1xEV-DO Revision B
– Enables operators to aggregate up to 15
1.25MHz channels
– Delivering 73.5Mbps throughputs
– Provides greater network efficiencies.
• The enhanced data rates enable services including
– Streaming video, streaming audio
– Broadcasts
– Videoconferencing
– Location and traffic services
LIDO
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CDMA2000 1xEV-DV
• CDMA2000 1xEV-DV (Enhanced Version–
Data and Voice)
• Integrates voice and data over the same
1.25MHz carrier.
• It is asymmetrical, supporting up to 4.8Mbps
downstream peak data rate and up to
307Kbps upstream.
LIDO
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CDMA2000 3X
• CDMA2000 3X uses three 1.25MHz CDMA
channels.
• It is part of the CDMA2000 specification for
countries that require 5MHz of spectrum for
3G use.
• CDMA2000 3X is also known as 3XRTT, MC3X, and IMT-CDMA Multi-Carrier 3X.
• CDMA2000 3X utilizes a pair of 3.75MHz
channels to promising to support integrated
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LIDO voice and data up to 3.09Mbps
CDMA450
• CDMA450 is a TIA-EIA-IS-cdma2000 (CDMA-MC)
system deployed in 450 MHz
– includes a family of standards developed by
3GPP2, published by TIA and approved by ITU
for IMT-2000: cdma2000 1X, cdma2000 1xEVDO and cdma2000 1xEV-DV
• It includes the same family of technologies as
CDMA2000.
• Currently, CDMA2000 1X and CDMA2000 1xEV-DO
are commercially available for the 450MHz band.
LIDO
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CDMA450 Advantages
• The advantages of CDMA450 derive from
LIDO
– spectral efficiency and high-speed data
capabilities of cdma2000
– expanded coverage afforded by a lower
frequency band
– larger cell size compared to other bands
– fewer cell sites required
– lower capital and operating expenditures to
service vast coverage areas
– CDMA450 requires only a small amount of
spectrum (1.25MHz).
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CDMA450 Solutions
• CDMA450 offers a solution for multiple
markets.
• CDMA450 is the only technology
commercially available that allows operators
to directly transition from a first-generation
system to next-generation services.
• CDMA450 is also one of the few technologies
that fits into 4MHz–5MHz of spectrum.
LIDO
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CDMA450 Applications
• The 450MHz band can be utilized to
LIDO
– provide broadband access for mobile or fixed data
users.
– serve public safety communication markets
• group communication
• high-speed data access
• push-to-talk
• video streaming
• dispatch services
– provide broadband access to schools, hospitals,
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and businesses.
CDMA450
2100 MHz
450 MHz
900 MHz
LIDO
1800 MHz
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3G Deployment Issues
•
•
•
•
•
•
•
•
•
•
LIDO
Seamless handover between 2G and 3G
Complexity of W-CDMA
3G standards still evolving
Initial speeds lower than promised
Cost and availability of 3G devices
Battery life
Size/weight of devices
Dual-mode handsets
Possible health risks of 3G handsets
Cost/ability of gaining new sites
98
Additional Barriers
• Differences in frequency allocation
• Properly assessing the demand in terms of
voice versus data versus video
• The cost and coverage associated with 3G
versus what already exists
• Lack of significant consumer demand
• Wi-Fi wireless LANs and WiMax wireless
MANs create competition
LIDO
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Beyond 3G
• While we are seeing more 3G networks being
deployed, there is already a buzz about its
enhancement, referred to as Beyond 3G (B3G),
Super 3G, and Ultra 3G.
• Since 2005, there has been appreciable growth in
– the number of 3G networks deployed
– more networks extending their coverage
– the number of available 3G-capable devices, with
reductions in their price.
– the number of customers
– the size of the network footprints
• 3G is making strides, despite its slow start.
LIDO
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Beyond 3G Enhancements
LIDO
• Beyond 3G enhancements include
– IP technologies for the back end
– faster data speeds
– new business applications
– and many consumer applications, including
interactive games, video services, audio
downloads, and location-based services
– QoS features
– Support for bridging between wireless and wired
networks.
101
• 4G and 5G developments are underway.
B3G Features
• The B3G vision involves 3G technologies, but also
– support bandwidths greater than 5MHz
– adds smarter and more efficient IP-based back-end
infrastructure
– adds additional one-way or two-way airlinks
• The intended result is to
–
–
–
–
–
–
LIDO –
improve spectral efficiency
allow for a great increase in system capacity
lower latency
increase data rates on both the downlink and uplink
support full mobility
support existing 3G networks
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reduce cost
B3G Visions
• Much of the B3G vision is based on a new
generation of handsets that are capable of handling
a wide variety of different technologies and
communications links.
• The overall concept is to allow the customers to use
the best airlink available to them and to support
voice and data services over the selected airlink.
• 3GPP has formed a study group to determine the
Long-Term Evolution (LTE) for W-CDMA/UMTS
radio access networks and system architectures.
LIDO
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The Fourth Generation (4G)
• 3G technology provides a huge expansion in mobile
capacity and bandwidth. 4G will do the same for the
spectrum of broadband communications.
• 4G is expected to disrupt today’s wired broadband
access alternatives, including DSL and cable
modems, by supporting mobility, and by being faster
and cheaper to deploy.
• 4G is expected to serve the next billion Web users
in developing countries.
• 4G is an evolution to increase the bandwidth,
enhance the quality of services, and reduce the cost
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LIDO of the resource.
4G Characteristics
• The main distinguishing characteristics
between 3G and 4G will be
– increased data rates
– enhanced multimedia services
– new transmission techniques
– new Internet access technology
– greater compatibility in interfacing with wired
backbone networks
– the addition of QoS and security mechanisms
• 4G will be based solely on packet switching.105
LIDO
4G Technologies
• Japanese carrier NTT DoCoMo claims its 4G
prototype phones can receive data at 100Mbps
while moving and at 1Gbps while standing still. The
company plans to have a 4G network in place by
2010.
• NTT DoCoMo's 4G tests used a method called
Variable-Spreading-Factor Orthogonal Frequency
Code Division Multiplexing (or VSF-OFCDM)
– increases downlink speeds by using multiple radio
frequencies to send the same data stream.
• MIMO was also used to further increase data
LIDO capacity.
106
4G Features
• 4G should support a wide range of data rates
– at least 100Mbps peak rates in full-mobility wide
area coverage
– and 1Gbps in low-mobility local area coverage
• The 4G vision includes
– asymmetrical and symmetrical services
– QoS for real-time services
– support for streaming audio and video
– an efficient transport of packet-oriented services
as well as broadcast and distribution services
LIDO
107
4G Features
• 4G supports smart, adaptive antennas and utilizes
an adaptive modulation or coding scheme.
• One of the main concerns about Because 4G
operates at high frequencies, there is a concern
that it will experience severe interference from
multipath secondary signals reflecting off other
objects.
• VSF-OFCDM is one of the proposed solutions to
this problem.
LIDO
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4G and IP
• 4G, an IP-based network, will be rolled out
using IPv6.
• In the 4G network, each node will be
assigned a 4G-IP address (based on IPv6),
which will be formed by a permanent "home"
IP address and a dynamic "care-of" address
that represents its actual location.
LIDO
109
4G Concerns
• 4G concerns involve cost and the
compatibility of various applications.
• 4G will increase interactions between
corroborating technologies.
• 4G developments began in 2002, and there
are many standards and technologies under
consideration, many of which are still in the
development stages.
• Therefore, no one can really say what the
future 4G network will look like and what
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LIDO services it will offer.
Beyond 4G – 5G Visions
• What we envision beyond 4G is a wireless
world with incredible transmission speed and
no limitation on access or zone sizes.
• 5G should comprise more intelligent
technologies that interconnect the entire
world without limits, creating a real wireless
world—what is sometimes referred to as the
wireless World Wide Web (WWWW).
LIDO
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LIDO Telecommunications Essentials®
Wireless Communications Basics
Lili Goleniewski
The LIDO Organization, Inc.
www. telecomessentials.com
+1-415-457-1800
[email protected]
Skypes ID: lili.goleniewski
Telecom Essentials Learning Center
www.telecomessentials.com
LIDO
Copyright © 2007- The LIDO Organization, Inc.
All Rights Reserved
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