19-06-2012, 04:09 PM
TELECOMMUNICATION FROM BSNL
[attachment=24832]
INTRODUCTON
BSNL
WIDE RANGE OF CAPACITY REPLACED ELECTRO MECHANICAL EXCHANGE –: C-DOT-128,C-DOT-256,C-DOT-512,C-DOT-1024,C-DOT-2048
ILT EXCHANGE AND E-10B EXHANGE ALSO USED BESIDES C-DOT EXCHANGE
WLL AND GSM
DOT PROVIDES THE FOLLOWING FACILITIES -:
TELEGRAPH SERVICES
TELEPHONE SERVICES – LOCAL CALLS,TRUNK CALLS,OVERSEA CALLS ETC
WIRELESS SERVICES – MOBILE WIRELESS SERVICES FOR POLICE,DEFENCE,METROLOGICAL DEPARTMENTS ETC
FAX SERVICES
BROADCAST TV CHANNELS
FIBER-OPTIC APPLICATION-
TELECOMMUNCATION APPLICATION ARE WIDE SPREAD, RANGING FORM GLOBAL NETWORKS TO DESKTOP COMPUTERS
POTS : CARRIERS USE OPTICAL FIBER TO CARRY PLAIN OLD TELPHONE SERVICE ACROSS THEIR NATION WIDE NETWORKS
LECs : LOCAL EXCHANGE CARRIERS USE FIBER TO CARRY THIS SAME SERVICE BETWEEN CENTRAL OFFICE SWITCHES AT LOCAL LEVELS AND SOMETIMES AS FAR AS NEIGHBORHOOD OR INDIVISUL HOME(FIBER TO THE HOME[FTTH])
OPTICAL FIBER ALSO USED EXTENSIVELY FOR TRANSMISSION OF DATA
HDTV : HIGH DEFINITION TELVISION
BIOMEDICAL : MAKE DIGITAL DIAGNOSTIC IMAGES
OTHER APPLICAATION : SPACE,MILITARY,AUTOMATIVE. ETC
Principle of operation
If the angel of incidence increases more than critical angel , the light is totally reflected back into the first material so that it does not enter the second material. The angel of incidence & reflection are equal & it is called Total Internal Reflection.
THE GSM FUNCTIONS
Transmission -the transmission of user information & signaling information
Radio Resources management (RR) –provides communication links between mobile stations and the MSC ,
manage the frequency spectrum and the reaction of the network to changing radio environment conditions
Mobility Management -
. Location management
. Authentication and security
4. Communication Management (CM)
. Call control.
. Supplementary Services management.
. Short message Services management.
5. Operation, Administration and Maintenance (OAM)
FREE SPACE OPTICS
FSO is an alternatives to fiber cables system without expenses of fiber
. Transmission up to 1.25 gbps at distance of 4 miles in full-duplex mode
. Uses low-powered infrared(IR) beam sent through open air by transceivers
. Uses unlicensed higher frequency
. It uses two different wavelength
(780nm & 1550nm)
[attachment=24832]
INTRODUCTON
BSNL
WIDE RANGE OF CAPACITY REPLACED ELECTRO MECHANICAL EXCHANGE –: C-DOT-128,C-DOT-256,C-DOT-512,C-DOT-1024,C-DOT-2048
ILT EXCHANGE AND E-10B EXHANGE ALSO USED BESIDES C-DOT EXCHANGE
WLL AND GSM
DOT PROVIDES THE FOLLOWING FACILITIES -:
TELEGRAPH SERVICES
TELEPHONE SERVICES – LOCAL CALLS,TRUNK CALLS,OVERSEA CALLS ETC
WIRELESS SERVICES – MOBILE WIRELESS SERVICES FOR POLICE,DEFENCE,METROLOGICAL DEPARTMENTS ETC
FAX SERVICES
BROADCAST TV CHANNELS
FIBER-OPTIC APPLICATION-
TELECOMMUNCATION APPLICATION ARE WIDE SPREAD, RANGING FORM GLOBAL NETWORKS TO DESKTOP COMPUTERS
POTS : CARRIERS USE OPTICAL FIBER TO CARRY PLAIN OLD TELPHONE SERVICE ACROSS THEIR NATION WIDE NETWORKS
LECs : LOCAL EXCHANGE CARRIERS USE FIBER TO CARRY THIS SAME SERVICE BETWEEN CENTRAL OFFICE SWITCHES AT LOCAL LEVELS AND SOMETIMES AS FAR AS NEIGHBORHOOD OR INDIVISUL HOME(FIBER TO THE HOME[FTTH])
OPTICAL FIBER ALSO USED EXTENSIVELY FOR TRANSMISSION OF DATA
HDTV : HIGH DEFINITION TELVISION
BIOMEDICAL : MAKE DIGITAL DIAGNOSTIC IMAGES
OTHER APPLICAATION : SPACE,MILITARY,AUTOMATIVE. ETC
Principle of operation
If the angel of incidence increases more than critical angel , the light is totally reflected back into the first material so that it does not enter the second material. The angel of incidence & reflection are equal & it is called Total Internal Reflection.
THE GSM FUNCTIONS
Transmission -the transmission of user information & signaling information
Radio Resources management (RR) –provides communication links between mobile stations and the MSC ,
manage the frequency spectrum and the reaction of the network to changing radio environment conditions
Mobility Management -
. Location management
. Authentication and security
4. Communication Management (CM)
. Call control.
. Supplementary Services management.
. Short message Services management.
5. Operation, Administration and Maintenance (OAM)
FREE SPACE OPTICS
FSO is an alternatives to fiber cables system without expenses of fiber
. Transmission up to 1.25 gbps at distance of 4 miles in full-duplex mode
. Uses low-powered infrared(IR) beam sent through open air by transceivers
. Uses unlicensed higher frequency
. It uses two different wavelength
(780nm & 1550nm)