Explain frequency division multiplexing, Computer Engineering

Assignment Help:

Explain FDM and show how CCITT standards help in building the base band?

Frequency Division Multiplexing: This is the process of combining some information channels through shifting their signals to various frequency groups in the spectrum therefore they can be transmitted simultaneously over common transmission service.

The bandwidth of a telephone speech signal is quite less than 4 kHz. Where, the available bandwidth on unloaded cables pair is fine above 100 kHz. Therefore this is possible, by using modulation techniques, for divide up the cable bandwidth then a number of telephone speech paths can be carried at the same time along a single cable pair. The normal arrangement contains 24 telephone channels per cable pair, the modulation in 24 channels being carried out within the two stages. In the primary stage, 12 channels are multiplexed together to form that is commonly termed as a basic group. This basic group arrangement is demonstrated in figure. Each of the 12 telephone signals are single side-band amplitude modulated on to carriers spaced at 4 kHz intervals 64 kHz to 108 kHz. The lower side-band (LSB) is utilized in every case. The 12 base-band signals are thus translated in the frequency band from 60 kHz 108 kHz as demonstrated. The block diagram for the channel translating equipment is specified in figure. To form a 24-channel system, to basic groups are occupied together. One basic group (B) is transmitted directly as this stands. Another basic group (A) is amplitude modulated on to a carrier are 120 kHz and the lower side-band is occupied such as to take the frequency range from 12 kHz to 60 kHz as demonstrated in figure. by using two stages of modulation for basic group A, this is possible to decrease the physical size of the component needed for the LSB filters of the figure, because the lowest cut- off frequency needed is at 64 kHz quite than 12 kHz when the whole block of 24 channels were assembled together in one stage of modulation.

855_Basic Group Arrangement.png

FIG - Basic Group Arrangement

1635_Channel Translating Equipment.png

FIG - Channel Translating Equipment


Related Discussions:- Explain frequency division multiplexing

Towers of hanoi problem, The Towers of Hanoi Problem Towers of Hanoi pro...

The Towers of Hanoi Problem Towers of Hanoi problem is described. There are three pegs on which disks are "threaded" (there are holes in the disks to allow them to be placed on

State the hardware faults and softwate faults, State the hardware faults an...

State the hardware faults and softwate faults - protection against hardware faults could be to keep backups or use GFS; use of UPS (in case of power loss) and parallel system a

Dbms, sketch a neat E-R diagram for hotel management system with real time ...

sketch a neat E-R diagram for hotel management system with real time example

Data structures.., in asingle function declaration what is maximum no of st...

in asingle function declaration what is maximum no of statements that may be recursive calls

Define b2b - business to business, B2B - Business to Business  It is a...

B2B - Business to Business  It is a mode of conducting business among two or more companies over the Internet, rather than more traditional modes like as telephone, mail, and f

How atoms differ from the arrangement of atoms in a liquid, Q. How does the...

Q. How does the preparation of atoms in mainly solids differ from the arrangement of atoms in a liquid? Answer:- The arrangement of atoms in solids are diverse from those

Show select tag and pull down lists, The next type of input is a Pull Down ...

The next type of input is a Pull Down List. With this type you have to employ in place of and it also has a closing tag. This control is used when we have a

Project on adaptive concept map, to develop an adaptive concept map providi...

to develop an adaptive concept map providing personalized learning for Operating System subject with text file(in any form like html,ppt,txt,doc,pdf)as input

Quantity amounts (data type quan), A field containing quantity amounts (dat...

A field containing quantity amounts (data type QUAN) must be assigned to a reference table and a reference field. Explain? As a reference table, a system table having all the v

Copy file from a floppy disk to the hard disk, Q. Copy file from a floppy d...

Q. Copy file from a floppy disk to the hard disk? While using a PC, often you need to copy file from a floppy disk to the hard disk or vice-versa.  For instance, you buy some s

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd