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 is a reference string, What is a reference string? An algorithm is...

What is a reference string? An algorithm is evaluated by running it on a exacting string of memory references and computing the number of page faults. The string of memory refe

Numbers of students must be integer, A school district has I neighbourhoods...

A school district has I neighbourhoods, J schools and G grades at every school. Every school j has a capacity of C jg for grade g. In every neighbourhood i, the student population

Show the format text in document window, Q. Show the format text in Documen...

Q. Show the format text in Document window? You can format text in Document window by setting properties in Property inspector. First, select the text you want to format and th

Explain about two-pass assembler, Q. Explain about Two-pass assembler? ...

Q. Explain about Two-pass assembler? Assemblers usually make two or more passes through a source program in order to resolve forward references in a program. A forward referenc

Value - elements of composition, Value Value is the relative amount of ...

Value Value is the relative amount of light and darkness in an image or a particular colour within an image. Value is also known as Tone and refers to the way the artist has re

What do you mean by electronic funds transfer, What do you mean by Electron...

What do you mean by Electronic Funds Transfer? Electronic Funds Transfer: It’s an electronic payment method which transfers the money value through one bank account to o

Illustrate the following list of consideration of Laptop, Illustrate the fo...

Illustrate the following list of consideration of laptop computers The following is a list for consideration: -  The processor must consume as little power as possible thus

Define a gate fix asic-based design in short, Define a Gate Fix ASIC-based ...

Define a Gate Fix ASIC-based design in short. Gate Fix ASIC-based design: A Gate Fix implies that a select number of gates and their interconnections may be subtracted or ad

Illustrate working of asynchronous counters, Q. Illustrate working of Async...

Q. Illustrate working of Asynchronous Counters? This is more frequently referred as ripple counter as the change that takes place in order to increment counter ripples through

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