Thread Subject: multi-band IIR filter

I need to Design a multi-band IIR filter using Matlab code that will efficiently reject frequencies outside of the frequency bands of interest, can anyone please help me? thanks

"PinkLab" wrote in message <iq3sot$3ts$1@newscl01ah.mathworks.com>...
> I need to Design a multi-band IIR filter using Matlab code that will efficiently reject frequencies outside of the frequency bands of interest, can anyone please help me? thanks

When you say multiband can you be more specific? How many stopbands do you have?

Without knowing your specifications, you can use fdesign.bandstop and then use cascade() to cascade your designs.

Wayne

I have three bands frequencies which i need to show and reject frequencies which are outside band of interest. any idea?

"PinkLab" wrote in message <iq3uds$79r$1@newscl01ah.mathworks.com>...
> I have three bands frequencies which i need to show and reject frequencies which are outside band of interest. any idea?

Have you tried my suggestion, or fdesign.bandpass with cascade.

Also, you can use fdesign.arbmag to design a multiband arbitrary magnitude filter.

Wayne

i am a beginner and need help please if you can show me what you mean ? thanks

"PinkLab" wrote in message <iq40f1$bdp$1@newscl01ah.mathworks.com>...
> i am a beginner and need help please if you can show me what you mean ? thanks

Have you read the help for fdesign.arbmag (Signal Processing Toolbox and DSP System Toolbox) or dfilt.cascade (DSP System Toolbox), there are examples there.

Wayne