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

What specifies by environment variable in cgi script, The Environment varia...

The Environment variable SCRIPT_NAME in CGI script specifies? In CGI script gives the path of URL after server name.

Define interrupt, Define interrupt. An interrupt is any exceptional eve...

Define interrupt. An interrupt is any exceptional event that causes a CPUU to temporarily transfer control from its present program to another program , an interrupt handler th

How can i execute a php script using command line, Just run the PHP CLI (Co...

Just run the PHP CLI (Command Line Interface) program and give the PHP script file name as the command line argument. For instance, "php myScript.php", assuming "PHP" is the comman

Different possible handover scenarios in a gsm network, Problem: (a) C...

Problem: (a) Cellular systems are based on two types of multiplexing, what are those two types of multiplexing? Describe how they are used to improve channel allocation in cel

What are links and associations, What are links and associations? Link ...

What are links and associations? Link is a physical or conceptual connection between objects. A link is an instance of an association.  Association is a explanation of group

Illustrate arithmetic shifts with example, Q. Illustrate Arithmetic shifts ...

Q. Illustrate Arithmetic shifts with example? Arithmetic shifts ARITHMETIC SHIFT LEFT and ARITHMETIC SHIFT RIGHT are same as LOGICAL SHIFT LEFT and LOGICAL SHIFT RIGHTexcept th

Minimum degree of t=1 for a b-tree, Why don't we permit a minimum degree of...

Why don't we permit a minimum degree of t=1 for a B-tree? According to the definition of B-Tree, a B-Tree of order n means that every node in the tree has a maximum of n-1 keys

Unix , how to write algorithum for unix progam

how to write algorithum for unix progam

Show the features of collaboration systems, Q. What are basic features that...

Q. What are basic features that collaboration systems might have? ANSWER: Three basic features of collaboration systems are Web-conferencing, project management,

Differentiate between the message and method in c++, Message in C++ : *...

Message in C++ : * Objects converse by sending messages to each other. * A message is sent to invoke a method in C++.   Method in C++: * Gives response to a message

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