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

Multiple valued logics, Multiple valued logics: Multiple valued logics...

Multiple valued logics: Multiple valued logics, where altered types of truth value such as "unknown" are may be allowed. These have some of the particular advantages of fuzzy

Draw the circuit of A/D converter using a V/F converter, Draw the schematic...

Draw the schematic circuit of an Analog to Digital converter using Voltage-to Frequency conversion and explain its principle of operation. Draw its relevant Waveforms. Ans:

Explain cache-only memory access model (coma), Cache-Only Memory Access Mod...

Cache-Only Memory Access Model (COMA) As we have considered earlier, shared memory multiprocessor systems can use cache memories with each processor for decreasing the execution

Example on multi-statement forall construct, Q. Example on Multi-statement ...

Q. Example on Multi-statement FORALL construct? The subsequent statements set every element of matrix X to sum of its indices.  FORALL (i=1:m, j=1:n)      X(i,j) = i+j an

What is loader, What is loader? Loader is a system software which havin...

What is loader? Loader is a system software which having a set of utility programs. It will load the object program to the memory.

What is a snooping cache, DNS cache snooping is not a term the author just ...

DNS cache snooping is not a term the author just made up, it is called and discussed by some notable DNS execution developers, and a few interested DNS administrators have prob

How do you find out if a linked-list has an end, By 2 pointers you can find...

By 2 pointers you can find it. One of them goes 2 nodes each time. The second one goes at 1 node each time. If there is a cycle, the one that goes 2 nodes every time will eventuall

Methods to resolve collision during hashing., What are the two methods to r...

What are the two methods to resolve collision during hashing. The two methods to resolve collision during hashing are: a) Open addressing and b) Chaining.

How a procedure define in assembly, Q. How a Procedure define in Assembly ?...

Q. How a Procedure define in Assembly ? Procedure is defined within source code by placing a directive of form: PROC A procedure is terminated using: ENDP The

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