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

Explain auto increment and auto decrement mode, Explain Auto increment and ...

Explain Auto increment and Auto decrement mode  The register is incremented or decremented after (or before) its value is used to access memory.  The address stored in the regi

DISCRETE STRUCTURES, SET 2I OF ALL INTEGERS WITH ZERO IS AN ABELIAN GROUP

SET 2I OF ALL INTEGERS WITH ZERO IS AN ABELIAN GROUP

Discuss about the bus and memory transfer, Discuss about the Bus and Memory...

Discuss about the Bus and Memory Transfer A read action implies transfer of information to outside environment from a memory word, whereas storage of information inside memory

Explain naming convention globals, Explanation The values of global vari...

Explanation The values of global variables can be used and changed all over the project within all scripts and libraries. However it is highly recommended to remain the number o

How branching takes place in instruction pipeline, How branching takes plac...

How branching takes place in Instruction pipeline. Explain with suitable examples

Project, the project database is avilable?

the project database is avilable?

Which two properties are on every validation control, Which two properties ...

Which two properties are on every validation control?  Two properties are:- a) Control to validate b) Error Message.

Two layer artificial neural networks, Two Layer Artificial Neural Networks:...

Two Layer Artificial Neural Networks: However decision trees are whenever powerful they are as a simple representation scheme. Whereas graphical on the surface that they can b

Host cache agents, Your task is to program software agents able to send and...

Your task is to program software agents able to send and receive messages according to the two Gnutella protocols above. Your solution should have two types of agents:   A

Extension of propositional logic, Extension of propositional logic: Aw...

Extension of propositional logic: Away from proving  theorems directly, and the other main use for rewrite rules is to prepare a statement just for use before we search for th

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