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.

Advantages of FIR over CIC filter in decimation

Status
Not open for further replies.

j3lda

Newbie level 1
Joined
May 30, 2015
Messages
1
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
8
Hello, I used in my diploma thesis decimating filter with factor 8 with optimalized FIR anti-aliasing filter. I need to clarify this solution - advantages of FIR and say why I chose FIR rather than CIC filter.
I heard that FIR is better than CIC filter while decimating with lower factors (under 10). Do you know why?
Do you know any other advantages of FIR and disadvantages of CIC?

Thank you very much for ideas
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
48,418
Helped
14,252
Reputation
28,765
Reaction score
12,941
Trophy points
1,393
Location
Bochum, Germany
Activity points
280,188
The question title involves a contradiction in terms, because a CIC decimator is a filter with finite impulse response as well.

So more exactly you are asking about using different FIR characteristics than CIC as a decimation filter. The general answer is quite simple, if you want a different frequency characteristic than (sin(x)/x)^n, you won't use a CIC.

CICs have been used and are still used due to there simple, resource saving (no multipliers) topology, but they lack of a steep cut-off characteristic that's often wanted in digital signal acquisition. An economic solution might be a multi-stage design with CIC and a different FIR in the last stage. Or CIC with a correction filter.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top