Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

about sinc function...

Status
Not open for further replies.

super

Full Member level 2
Joined
Aug 18, 2002
Messages
125
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,296
Activity points
904
Dear all :
somebody can tell me what is "sinc" function and
what's physical mean ?

thanks.
 

zorro

Advanced Member level 4
Joined
Sep 6, 2001
Messages
1,131
Helped
356
Reputation
710
Reaction score
298
Trophy points
1,363
Location
Argentina
Activity points
8,907
Hi super,

sinc(x) = sin(pi*x)/(pi*x)

It is the Fourier transform of a rectangular pulse.
Regards

Z
 

super

Full Member level 2
Joined
Aug 18, 2002
Messages
125
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,296
Activity points
904
Thanks zorro,
I want to know the physical mean .
Why we need it and what's the benefit
and where we can use it ?

Thanks .
 

cpt

Newbie level 4
Joined
Sep 11, 2006
Messages
6
Helped
2
Reputation
4
Reaction score
0
Trophy points
1,281
Activity points
1,317
A perfect "brick-wall" filter in the frequency domain has a time domain transform of a sinc function, hence the name "sinc filter". This kind of filter is physically impossible to implement, but is often used in theoretical concepts.

There is another kind of filter called "raised cosine filter", which is physically realisable, and also has the desirable property of zero inter-symbol interference when used as a pulse shaping filter in communications. And the sinc function is actually an extreme special case of the raised cosine function.
 

    super

    Points: 2
    Helpful Answer Positive Rating

electronics_kumar

Advanced Member level 2
Joined
Nov 29, 2004
Messages
659
Helped
34
Reputation
68
Reaction score
9
Trophy points
1,298
Location
Tamilnadu
Activity points
5,552
like inverted BELL structure whose tail(on both directions) run towards infinity by alternating between positive and negative values. i mean unlimited BAND....this is true for f domain

in time domain structure is BANDLIMITED one
 

super

Full Member level 2
Joined
Aug 18, 2002
Messages
125
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,296
Activity points
904
thanks everyone help,
It means sinc function is only appear in formula ,
but didn't have this filter in real world .

thanks...
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top