Gsm Global System For Mobile Comm. Really NicePresentation Transcript
INTRODUCTION TO CELLULAR TECHNOLOGY GSM-GLOBAL SYSTEM FOR MOBILE COMMUNICATION RAHUL GUPTA
TRAINING CARRIED AT
MOBILTY THE MAGIC WORD
IN THIS DAY & AGE ,MANY FOLKS NEED TO BE ACCESSIBLE EVERYWHERE ,WHETHER THEY’RE AT WORK OR PLAY,IN THE OFFICE OR AT HOME .
WHAT IS NEEDED FOR MEETING THIS DEMAND?
GSM: GLOBAL SYSTEM FOR MOBILE COMMUNICATION
Global system for mobile communication (GSM) is a globally accepted standard for digital cellular communication .GSM is the name of a standardization group established in 1982 to create a common European mobile telephone standard that would formulate specifications for a pan-European mobile cellular radio system operating at 900 MHz .it is estimated that many countries outside of Europe will join the GSM partnership.
EVOLUTION OF MOBILE TELEPHONE SYSTEMS
PCS-United States 1996 CDMA 1995 GPRS 2003 PCS-1900 1995 Personal digital cellular 1994 Digital cellular system 1992 GSM 1991 American digital cellular 1991 Nordic mobile technology 1986 Total access communication system 1985 American mobile telephone system 1983 Nordic mobile telephone 1981 MOBILE SYSTEM YEAR
OSI ARCHITECTURE PSTN PSPDN ISDN Um Abis A MS BTS BSC MSC
The air interface Um
OSI layer structure
Enable physical transmission
Assessment of channel quality
DATA LINK LAYER
Multiplexing of the signal channels
Management of location data
ITU (international telecommunication union) has allocated following bands: GSM 900: uplink : 890-915 MHz downlink:935-960 MHz GSM 1800: uplink : 1710-1785 MHz downlink:1805-1880 MHz * TDMAFDMA scheme * BURST – fundamental unit in the TDMA scheme
Protocols on the air interface
Layer 1: Um interface
Layer 2: LAP-Dm protocol
Layer 3: Radio Resource Management (RR): to establish and release stable connection between mobile stations (MS) and MSC for the duration of a call
- Cell selection,
- Monitoring and forwarding of radio connections,
- Introduction of encryption,
Mobility management (MM) handles control functions for mobility
- Assignment of TMSI,
- Management of subscriber location.
Connection management (CM) set up, maintain calls - connections - Call control (CC): Manages call connections,
- Supplementary service support (SS): special services,
- Short message service support (SMS): Transfers brief texts.
Users identity& authentication
User identity & authentication
GSM –SUBSCRIBER SERVICES
Telephony services(teleservices )
These are mainly voice services that provide subscriber with the complete capability(including necessary terminal equipment) to communicate with other subscribers.
Data services(bearer services)
These provides the capacity necessary to transmit appropriate data signals between two access points creating an interface to the network .
- Facsimile group
- Call forwarding
-Baring of outgoing calls
-Baring of incoming calls
-Calling line identification presentation
GSM V/S CDMA 127 MILLION USERS 456 MILLION USERS INTERNATIONAL ROAMING 64-140kbps 56 kbps DATA RATE SOFT MAKE BEFORE BREAK HARD BREAK BEFORE MAKE HANDOVER SPREAD SPECTRUM TECHNOLOGY FDMA TDMA TECHNOLOGY USED CDMA GSM PARAMETERS
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