MOBILE
COMMUNICATIONS


PRESENTED BY:
MIHIR RAO
 SWAPNIL RANE
 AMOL HATKAR
 MAZHAR NOORI
 SYED JAVED
 AATIF MODAK
 AZEEM HASHMANI
 MUBIN
COMMUNICATION
ABOUT:

IT IS THE PROCESS WHEREBY THE MEANINGFUL INFORMATION IS
TRANSFERRED FROM ONE POINT (LOCATION) CALLED SOURCE IN
SPACE TO THE OTHER POINT (LOCATION) CALLED DESTINATION (OR
USER).
 IT IS A TWO -WAY TRANSMISSION & RECEPTION OF DATA STREAMS.
 THE SCIENCE OF COMMUNICATION INVOLVING LARGE DISTANCE IS
CALLED TELE-COMMUNICATION.
TYPES:
 WIRE (OR LINE) COMMMUNICATON.
 WIRELESS (OR RADIO) COMMUNICATION.
(MOBILE COMMUNICATION COMES UNDER WIRELESS COMMUNICATION)
FREQUENCY BANDS FOR MOBILE COMMUNICATION

THE CURRENT FREQUENCY SPECTRUM ALLOCATION FOR CELLULAR
MOBILE RADIO IN USA IS 50MHz WITHIN THE 824 TO 849 MHz AS UP-LINK
FREQUENCY BAND & 869 TO 894 MHz AS DOWN-LINK FREQUENCY
BANDS.

50MHz LEADS TO TOTAL OF 832 FULL DUPLEX CHANNELS. OUT OF
WHICH 416 CHANNELS, 21 CHANNELS ARE USED AS SETUP (CONTROL)
CHANNELS, WITH REMAINING 395 CHANNELS FOR USER TRAFFIC.

THE OTHER 416 CHANNELS ARE SHARED BY TWO OPERATORS NAMELY
WIRELESS COMMON CARRIER (WCC) & THE RADIO COMMON
CARRIER (RCC).
TYPES OF MODULATIONS USED

THE FIRST GENERATION (1G)(ANALOG) CELLULAR SYSTEMS USE FM
FOR SPEECH TRANSMISSION & FSK FOR SIGNALING.

THE SECOND GENERATION (2G)(DIGITAL) CELLULAR SYSTEMS ARE
BASED ON TDMA & CDMA TECHNOLOGY USE PCM WITH VOICE
TRANSMISSION RATE OF 24 KBPS OR HIGHER FOR COMMERCIAL
USES.

THE GSM TECHNOLOGY WHICH IS USED ALMOST WORLD WIDE.IT
USES TDMA & FDMA FOR MODULATIONS.

GSM EDGE (ENHANCED DATA RATES FOR GSM EVOLUTION) IS THE
THIRD GENERATION (3G) VERSION NEWLY USED.
BASIC MOBILE TELEPHONE SERVICE NETWORK
GENERAL BLOCK DIAGRAM OF A CELULLAR RADIO
CELLULAR CONCEPT

A SMALL GEOGRAPHIC COVERAGE AREA OF A BASE STATION WITH
A DIAMETER OF 2 TO 50 KM EACH OF WHICH A NUMBER OF RF
CHANNELS IS CALLED A CELL.

GEOMETRIC SHAPES OF CELL ARE: A SQUARE, AN EQUILATERAL
TRIANGLE, A HEXAGON.
A HEXAGONAL CELL
CELLULAR SYSTEM ARCHITECTURE
FREQUENCY REUSE

THE DESIGN PROCESS OF SELECTING & ALLOCATING RF CHANNEL
GROUPS FOR ALL OF THE CELLULAR BASE STATIONS WITHIN A
CELLULAR SYSTEM IS CALLED FREQUENCY REUSE OR FREQUENCY
PLANNING.
CELL SPLITTING
HANDOFF MECHANISM
WIRELESS COMMUNICATION TECHNIQUES

THERE ARE THREE IMPORTANT TECHNIQUES ;
1) CDMA (CODE DIVISION MULTIPLE ACCESS).
2) FDMA (FREQUENCY DIVISION MULTIPLE ACCESS).
3) TDMA (TIME DIVISION MILTIPLE ACCESS).

FROM THE ABOVE TECHNIQUES, CDMA IS THE MOST USED & IMPORTANT
ONE.
CDMA
(METHODS & VERSIONS)

CODING METHODS:
1) AUTO CORRELATION CODES.
2) ORTHOGONAL CODES.
3) WALSH CODES.
4) SCRAMBLING CODES.
5) CHANNELIZATION CODES.
6) CARRIER MODULATION CODES.

CDMA VERSIONS:
1) W-CDMA (WIDEBAND)
2) 3G CDMA -2000
3) TD-SCDMA (TIME DIVISION- SYNCHRONOUS)
GSM TECHNOLOGY
HISTORY

THE CONFERENCE OF EUROPEAN POSTAL & TELECOMMUNICATIONS
ADMINISTRATIONS (CEPTA) DEVELOPED THE GSM STANDARDS FOR
TDMA SYSTEM IN JUNE 1982.

THEY MADE IT TO SERVE TWO MAIN OBJECTIVES;
1) EUROPEAN ROAMING THROUGHOUT THE CONTINENT,
2) INTERACTION WITH ISDN.

THE FIRST COMMERCIAL GSM SYSTEM CALLED D2, WAS
IMPLEMENTED IN GERMANY IN 1992.
GSM FREQUENCY RANGES

MOST ‘2G’ GSM NETWORKS OPERATE IN 900MHz TO 1800MHz BANDS.

MOST EUROPEAN ‘3G’ GSM NETWORKS OPERATE IN 2100MHz BANDS.

‘2G’ GSM USES 890 TO 915 MHz FOR UPLINK & 925 TO 960 MHz FOR
DOWNLINK PRONIDING 125 RF CHANNELS SPACED AT 200KHz.
DUPLEX SPACING OF 45 MHz IS USED.

THEY HANDLE LOW SPEED DATA SERVICES (UPTO 9.6 KBPS).
GSM SERVICES

TELESERVICES: SMS, EMREGENCY CALLING,FAX,MMS,VIDEOTEX,TETLTEX

BEARER (OR DATA) SERVICES:FULL DUPLEX, TRANSPARENT, NON
TRANSPARENT DATA TX.,SYNCHRONOUS OR ASYNCHRONOUS PACKAGE DATA
(GPRS).

SUPPLEMENTARY (ISDN) SERVICES: CALLER ID, CALL WAITING, CALL
HOLD, CALL BARRING, CLOSED USER GROUP, TELE- CONFERENCING ETC..
GSM ARCHITECTURE
SUBSCRIBER INDENTITY MODULE
(SIM)

In addition to the battery, GSM mobile phones require a small microchip,
called a Subscriber Identity Module or SIM CARD, to function.
 the SIM Card is usually placed underneath the battery in the rear of the
unit, and (when properly activated) stores the phone's configuration
data, and information about the phone itself, such as which calling plan
the subscriber is using.
 When the subscriber removes the SIM Card, it can be re-inserted into
another phone that is configured to accept the SIM card[16] and used as
normal.
CALL FLOW SEQUENCE
THE TYPICAL SIGNALING SEQUENCES FOR CALL FLOW IN
GSM ARE AS FOLLOWS:

LOCATION UPDATING.
 MOBILE CALL ORIGINATION.



MOBILE CALL TERMINATION
AUTHENTIFICATION & CIPHERING.
INTER-MSC CALL HANDOFF.
MOBILE CALL ORIGINATION IN GSM
MOBILE CALL TERMINATION IN GSM
ADVANTAGES:
HIGH COVERAGE RANGE & AREA.
 GOOD SPEECH QUALITY.
 LARGE VARIETY OF DATA & SUPPLEMENTARY SERVICES.
 PROVIDES SEAMLESS GLOBAL ROAMING.

APPLICATIONS:





PAGING & SMS’s
EMAIL & INTERNET ACCESS
INVENTORY CONTROL
DATA INPUTS.
CREDIT CARD AUTHORIZATIONS (FROM REMOTE LOCATIONS)
REFERENCES
WEBSITES:
www.google.com
 www.wikipedia.com
 www.telecomindia.com

BOOKS:

MOBILE COMMUNICATION BY V.G. YANGALVAR, R.C. JAISWAL,
& GANESH B. AKOLIYA
THANK YOU