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General Packet Radio Service
BSNL
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Evolution from GSM to 3G
GSM
2G
HSCSD
GPRS
2.5G
EDGE
3G
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GSM Evolution
GPRS200 KHz carrier115 Kbps peak data rates
EDGE200 KHz carrierData rates up to 384 Kbps8-PSK modulationHigher symbol rate
UMTS5 MHz carrier2 Mbps peak data ratesNew IMT-2000 2 GHz spectru
GSM200 KHz carrier8 full-rate time slots16 half-rate time slots
GSM GPRS EDGE UMTS
3G2.5G2G
HSCSD
HSCSDCircuit-switched data64 Kbps peak data rates
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Mobile Data Technologies
HSCSD
GPRS
EDGE
UMTS
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Mobile Data Technologies
HSCSD
GPRS
EDGE
UMTS
High Speed Circuit Switched Data
GSM Phase 2+ service (2.25 G)
Using Multiple Time slots
14.4 Kbps to 57.6 Kbps
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Mobile Data Technologies
HSCSDGPRS
EDGE
UMTS
General Packet Radio Service
GSM Phase 2+ service (2.5G)
From 9.05 Kbps to 171.2 Kbps
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Mobile Data Technologies
Enhanced Data Rates for GSM Evolution (2.75 G)
14.4/28 Kbps to 384/512 Kbps
EGPRS
HSCSD GPRS
EDGE
UMTS
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Mobile Data Technologies
HSCSD GPRS
EDGE
UMTS
Universal Mobile Telecommunication System
3G standard
Using W-CDMA technology
Data rates up to 2 Mbps
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GSM Conventional Data Service Problems
Low Speed 9.6 Kbps Data rates (High Data rates with HSCSD)
Long connection setup time
Long connection setup time up to half a minute.
Circuit Switched Data Service Charging is based on amount of time not amount of data
Channels are occupied continuously during the operation.
No GSM standard is defined for direct connection to
the Internet.
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GSM Conventional Data Service Problems
Separate agreement with an ISP. Internetconnection may not be available duringroaming.
SMS is also a data service but it is designed
to carry 160 characters long short textmessages not continuous data. It usescommon channel signaling channels notTraffic channel.
Transmission of music samples, pictures,graphical short messages, MMS notsupported
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Operator Requirements
Better utilization of Radio Resources
Get more users = More Money
Simplified Access to data networks
Divide Users to Categories
Operators will become ISP's
Minimum modifications on the existing
infrastructure
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User Expectations
Cheaper Access to Data Networks
Higher Data Transfer Rates
Shorter Connection Setup Time
Better Support for Roaming
Less Connection Drops
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What is GPRS ?
Packet Data Network overlaid on todaysGSM Circuit Switched architecture
Circuit Switching is wasteful of valuable
spectrum - packet data is more efficient Subscribers will be permanently connected
- just like PC in the office LAN
The Mobile Phone will become a window onthe Internet and Corporate Intranets
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Channel Sharing
BTS
BCCH GPRS GPRS GPRS GPRS GPRS GPRS GPRSUser rate atCS2 = 93.8 kbps
BTS
BCCH GPRS TCH TCH TCH TCH TCH User rate atCS2 = 13.4 kbps
TCH
Dynamic allocation of channels between circuit and packet:
One timeslot allocated to GPRS
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Data Rate & Coding Schemes for GPRS
Scheme Code Rate Data Rate Max. Data
Per Timeslot Rate
CS-1 1/2 9.05kbps 72.4 kbps
CS-2 2/3 13.4kbps 107.2 kbps
CS-3 3/4 15.6kbps 124.8 kbps
CS-4 1 21.4kbps 171.2 kbps
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Network Area Routing Area (RA) can consist of one or more
cells and is always served by only on SGSN.
However, one SGSN could serve more than
one Routing Area.
Location Area (LA) can contain one or moreRouting Areas, but one Routing Area could
not span more than one Location Area.
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Classes of GPRS Mobiles Class A
Simultaneous execution of circuit switched and GPRSoperation (including SMS) is possible
user can make/receive calls on both services simultaneously
Class B Simultaneous execution of signaling for both circuit switched
and GPRS operation is possible
GPRS traffic will be suspended during an established orpending circuit switched connection
can be attached to both services but only one type of serviceat a time
Class C Alternate use of circuit switched and GPRS operation
User can receive/make calls from default/manually selectedservice
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GPRS Network
Internet
X.25 Network
GSM Network
With GPRS
Capability
MS
BSNL
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GPRS Architecture
Radius
Server
Charging
Gateway
WAP
Server
Mediation
Billing
MS
GGSN
GGSN
SGSN
MSC
BSC PCU
PSTN
GPRS
Network
Intranet
Internet
BSNL
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GPRS Architecture
EIR
SGSN HLR
AUC
GGSN
ISDN / PSTN / PLMN
Network
IP-Backbone
Network
ExternalIP Network
External
X.25 Network
GMSC
MSC/VLR
A
Gb
Gs
Gn
Gf
Gr
Gi
Gi
Gn
BTS
BSC
Abis
BSS
Um
TE
MT
MS
A GSM Interface
Abis GSM Interface (Proprietary of M/s Ericsson)
AUC Authentication Center
BSC Base Station Center
BSS Base Station System
BTS Base Transceiver Station
EIR Equipment Identity RegisterGGSN Gateway GPRS Support Node
GMSC Gateway Mobile services Switching Center
Gx GPRS Interfaces
HLR Home Location Register
MS Mobile Station
MSC Mobile services Switching Center
MT Mobile Terminal
SGSN Serving GPRS Support Node
TE Terminal Equipment
Um Air Interface
VLR Visitor Location Register
GPRS Network ElementsGSM Network Elements Traffic & Signaling Signaling
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EDGE (2.75G)
BSNL
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The Abbreviation
GPRS = General Packet Radio System
EGPRS = GPRS + EDGE modulation
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M
SBTS
P
U
C
BSC MSC/VL
R
HLR
SGS
N
GGSN
Backbone
Network
ISP
Network
CorporateNetwork
AUC
SMS G/IW MSC
Gb
Gd
Gs
Gn
Gr
Gn
GiEDGE
TRUM
S
Evolution to EDGE
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voice voice voice voice voice
voice voicevoicevoice voiceFree
TS DataFree
TS
Standard GSM Transceiver
EDGE Transceiver
EDGE increases capacity
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System upgrade forEDGE
B
S
C
BSC Software Upgrade
R
B
S
EDGE TRU
EDGE enabled RBS
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What JKJDFDSSWWhat EDGE would mean to subscriber ?
Streaming Applications Very high speed downloads
Corporate Intranet connections
Quicker MMS Video Phone
Vertical corporate applications Video
Conference, Remote presentations
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Enhanced Data for GSM Evolution
Next step towards 3G for GSM/GPRS Networks
EDGE adopts the GSM standards such as
same frequency plan, meaning that 200kHz will stillseparate carriers
TDMA structure supported by GSM will remain intact ateight timeslots per frame
same relationship between logical and physicalchannels.
Increased data rate up to 384 Kbps by bundling up to 8channels with 48 Kbps/channel
GPRS is based on modulation technique known as GMSK.
EDGE is based on a new enhanced modulation scheme thatallows a much higher bit rate across the air-interface called8PSK (OPSK) modulation.
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Enhanced Data for GSM Evolution
EDGE maintains a good quality link byautomatically adapting to the radio
interference conditions and thereby
provide the highest possible rate.
Since 8PSK will be used for UMTS,
network operators will be required to
introduce this at some stage before
migration to 3G.
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