evolution of wireless communication by chandra thapa
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Evolution of Wireless Communication By Chandra Thapa. Evolution of Wireless Systems. Guglielmo Marconi invented the wireless telegraph in 1896 Communication by encoding alphanumeric characters in analog signal Sent telegraphic signals across the Atlantic Ocean - PowerPoint PPT PresentationTRANSCRIPT
Evolution of Wireless Communication
By
Chandra Thapa
Evolution of Wireless Systems
Guglielmo Marconi invented the wireless telegraph in 1896Communication by encoding alphanumeric characters in
analog signalSent telegraphic signals across the Atlantic Ocean
First public mobile (car-based) telephone system (MTS) introduced in 1946Analog frequency modulation High power BS tower to cover 50 miles radius Inefficient (120K spectrum for a voice connection)
Evolution of Wireless Sys. (Contd)Improved mobile telephone system (IMTS) developed
in 1960Full duplex services and direct-dialing23 FM channels with BW reduced to 25-30 KHz
Cellular concept Exploits the attenuation of radio signal with
distance to achieve frequency reuse.originally proposed by D. H. Ring in 1947Bell Labs began work on cellular telephone system
in the late 1960s.
Evolution of Wireless Sys. (2.5G)2G telephony is highly successfulEnhancement to 2G on data service
GSM: HSCSD and GPRS IS-95: IS-95b IS-136: D-AMPS+ and CDPD
The improved data rate is still too low to support multimedia traffic
ITU initiated 3G standardization effort in 1992, and the outcome is IMT-2000.
Evolution of Wireless Sys. (1G)Handoff was not solved until the development of
microprocessor, efficient remote-controlled RF synthesizer, and switching center.
1G Cellular SystemDesigned in 1970s, deployed in early 1980sAnalog, 42 control channels, 790 voice channelsHandoff performed at BS based on received powerAMPS in US; TACS in part of Europe; NTT in Japan; C450
in West German, and NMT in some countries. Became highly popular; AMPS still popular in US!
Evolution of Wireless Sys. (2G)
2G Systems Digital cellular telephonyModest data support, incompatibleGSM: a common TDMA technology for Europe; claim
about 3/4 of subscribers worldwide. IS-54 and IS-136: TDMA technology in US; compatible
with AMPS; IS-95: CDMA; standardized in 1993; South Korea and
Hong Kong deployed it in 1995; US in 1996.
Evolution of Wireless Sys. (3G)IMT-2000 comprises several 3G standards:EDGE, data rate up to 473Kbps, backward compatible
with GSM/IS-136 cdma2000 (Qualcomm), data rate up to 2Mbps, backward
compatible with IS-95WCDMA (Europe), introduces a new 5MHz channel
structure; data rate up to 2Mbps;TD-SCDMA (China), CDMA in TDD fashion
Evolution of Wireless Sys. (4G)Problems of 3G systems
Immature 3G license auction increases the financial burden
Difficult to extend to higher data ratesNo unified standard (political factors dominate)
4G systemsResearch initiated, but still not well-definedData-oriented, seamless integrated with wirelineIndoor data rate up to 100 Mbps, outdoor data rate
up to 20Mbps.
Evolution of Mobile Radio Communications
AMPS
VoiceServiceTrack
CDMAIS-95
CDMA2000
4G
ETACS GSM
WCDMA
1st GenerationAnalog
2nd GenerationDigital
3rd GenerationWideband
FixedComputerNetwork
WLAN
PDMA
NorthAmerica
Europe
DataServiceTrack
Voice & DataServiceTrack
4th GenerationWideband All-IP
Notes:IP: Internet ProtocolTCP: Transmission Control ProtocolAMPS: Advanced Mobile Phone ServicesETACS: European Total Access Communication SystemPDMA: Packet Division Multiple Access (Hanwang, China)
Circuit Switching
Packet Switching
Circuit and Packet Switchingevolving to Packet Switching
TD-SCDMAChina
Trends in Wireless Comm. Personal Communications (Goal of mobile communications) All IP based (IPv6) (Packet switched) Flexible platform of complementary access
systems( Combination of different wireless access systems, Hot spot services will be introduced by high-speed wireless access (>100mbps))
Higher system capacity (Users/Service, 5-10 times higher than
3G) Higher Transmission Data rate Higher frequency efficiency More advanced multimedia applications Improved QoS Realize high levels of security and authentication Global coverage Global roaming
All IP Based
All IP based
Internet
PSTNISDN
IP/ATM/MPLS Backbone
Mobile Internet Application Platforms
Mobile InternetApplication Servers
Media Gateway
Mobility, Connection& Control Servers
Mobility Gateway Intelligent Edge
Broadband Gateway
IP MultiRadio
OWLAN
Broadband Accesses
Network Domain
Service Domain
Combination of different wireless access systems
IEEE.802.11 WLAN
WPAN WLAN WWAN
PAN Bluetooth PDMA
Network of 3G beyond
Services andapplications
IP based core network
IMT-2000UMTS
WLANtype
cellularGSM
short rangeconnectivit
y
WirelinexDSL
otherentities
DABDVB
return channel:e.g. GSM
download channel
New radiointerface
Transmission Data Rate Highest data rate(3G)
at least 144 Kb/s in a vehicular environment, 384 Kb/s in a pedestrian environment, 2048 Kb/s in an indoor office environment.
Highest data rate (4G) 2Mbps in a vehicular environment, 20Mbps in a pedestrian
environment Wide Area, high velocity: 100Mbps Indoor, lower velocity: 1Gbps
Evolution of transmission data rate
Drivers of 3G Beyond
3G evolution :Difficult
to extend to higher data rate with CDMA only technology;
to provide various services with different QoS
to have enough frequency resource to accommodate more subscribers
Drawback Low system capacity Low spectrum efficiency
MobileInternetUser
MobileUser
0
200
400
600
800
1000
1200
1400
1600
1800
1995 2000 2005 2010
Subscriptions (millions)MobileFixedMobile InternetFixed Internet
Drivers of 3G Beyond
3G2G
Revolution from subscriber service expectations
Evolution from 2G systems
IP
Revolution from IP infrastructure
and Beyond
Multimedia Services
Internet accessShopping/banking(e-commerce)Video conferencingVideo on demandTelemedicineDistance learning
Challenges
Unreliable ChannelsScarce Spectrum and Resource ManagementStringent Power BudgetSecurityLocation and RoutingInterfacing with Wired NetworksHealth ConcernDiversified Standards and Political Struggle