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

Two methods of copying a information document, There are basically two meth...

There are basically two methods of copying: Photocopying This is a modified development of photography. It is quite expensive and slow and is not often used for routine rep

Interfacing subroutines with parameter passing, Interfacing Subroutines wit...

Interfacing Subroutines with Parameter Passing Let's now write a C program which calls the assembly program for parameter passing. Let's extend the previous two programs such t

Dynamic memory allocation function, Name the dynamic memory allocation func...

Name the dynamic memory allocation function? Three dynamic memory allocation functions are: a) malloc, b) calloc and c) free.

Explain the use of functions in parallel programming, Q. Explain the Use of...

Q. Explain the Use of functions in parallel programming? include "pvm3.h" main() {    int cc, tid, msgtag;    char buf[100];    printf("%x\n", pvm_mytid());

How are control signals achieve the particular operation, Q. How are contro...

Q. How are control signals achieve the particular operation? The control signals are applied directly as binary inputs to the logic gates of the logic circuits. All these input

What is double data rate sdram, What is double data rate SDRAM?  Double...

What is double data rate SDRAM?  Double data rates SDRAM are those which can transfer data on both edges of the clock and their bandwidth is fundamentally doubled for long burs

Concurrently read concurrently write, Q. Concurrently read concurrently wri...

Q. Concurrently read concurrently write? It is one of the models derived from PRAM. In this model the processors access the memory locations simultaneously for reading and writ

When the divide overflow is generated, Divide overflow is generated when ...

Divide overflow is generated when  (A) Sign of the dividend is dissimilar from that of divisor.  (B) Sign of the dividend is same as that of divisor.  (C) The first part

What is Video Card Interfaces, Q. What is Video Card Interfaces? A video i...

Q. What is Video Card Interfaces? A video interface is the link of video system to rest of the PC. To improve video performance there is required to be an intimate connection betw

User interface (ui), Design a easy (text-based/ graphical) UI for  your pr...

Design a easy (text-based/ graphical) UI for  your program.  The user should be encouraged for  parameter values for  the particular protocol simulation. For  example, the user sho

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