Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...

What is meant by pre-emphasis and de-emphasis?

Answer Posted / debopam banerjee

PRE-EMPHASIS :-

In an FM system the higher frequencies contribute more to
the noise than the lower frequencies. Because of this all FM
systems adopt a system of preemphasis where the higher
frequencies are increased in amplitude before being used to
modulate the carrier. The transfer function sketched above
is used for a preemphasis circuit for FM signals in the FM
band. The Time T = 75µs. For FM systems in the FM band m ~ 5
resulting in a S/N improvement of 19dB. With preemphasis
this can be increased by 4dB for a total of 23dB.





DE-EMPHASIS :-

At the receiver the higher frequencies must be deemphasised
in order to get back the origunal baseband signal. The
transfer function of the deemphasis circuit is shown above.

Is This Answer Correct ?    94 Yes 25 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Define amplitude modulation?

961


What is meant by commutation?

1057


plz give the question about interview to the post JR.Executive (ATC)

2685


what is an adder or summing amplifier?

1024


What is a rectifier, what are its various types?

1004


y do v use single anteena in radar any other reason except cost???

1920


I've an interview for post of Lecturer in a ece Department. Can anyone send me some possible questions that can be helpful for me???????

15780


Explain the difference between plc and dcs?

990


What are the different methods of firing circuits for line commutated converter?

2153


How many type of resistor are there in diode?

953


What is am.

1027


What is the function of freewheeling diodes in controlled rectifier?

1163


how can trace the fault in any PCB? what are the steps to find problem & to troubleshoot?

2002


Explain how to format a memory card by using memory card?

1082


Wht is meant by booy strap?

2209