The way to do FIR filter.

[boki]

I found there are two method to do FIR.

A. find the coefficient from fourier series.
B. Window method.

My thinking about A.

1. Use fourier series to contribute a desire filter curv(ac response)
2. find fourier series
3. convolution signal with series
4. Get the FIR.


I am correct?

Thank you very much.

Best regards,

Boki.

 

[Bob Masta]

On 4 Jun 2004 17:20:15 -0700, bokiteam@ms21.hinet.net (boki) wrote:

I found there are two method to do FIR.

A. find the coefficient from fourier series.
B. Window method.

My thinking about A.

1. Use fourier series to contribute a desire filter curv(ac response)
2. find fourier series
3. convolution signal with series
4. Get the FIR.


I am correct?

Thank you very much.

Almost. You find the Fourier series for the
filter, then do an inverse Fourier transform to
get the time-domain impulse response of the
filter. That impulse response is itself the
FIR tap weights.

But unless you need a lot of control over the
exact shape, the window method is a lot
simpler.



Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

 

[boki]

Thanks for the way.

Best regards,
Boki.


NoSpam@daqarta.com (Bob Masta) wrote in message news:<40c1d3e4.3201238@news.itd.umich.edu>...

On 4 Jun 2004 17:20:15 -0700, bokiteam@ms21.hinet.net (boki) wrote:

I found there are two method to do FIR.

A. find the coefficient from fourier series.
B. Window method.

My thinking about A.

1. Use fourier series to contribute a desire filter curv(ac response)
2. find fourier series
3. convolution signal with series
4. Get the FIR.


I am correct?

Thank you very much.

Almost. You find the Fourier series for the
filter, then do an inverse Fourier transform to
get the time-domain impulse response of the
filter. That impulse response is itself the
FIR tap weights.

But unless you need a lot of control over the
exact shape, the window method is a lot
simpler.



Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com