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Complex Coefficients with FIR Compiler II

Altera_Forum
Honored Contributor II
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Is it possible to use complex coefficients with the FIR Compiler II? If so, what notation is used to specify this when loading coefficients from a file into the wizard? I've tried i and j, but the wizard is complaining about invalid coefficients.

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Altera_Forum
Honored Contributor II
105 Views

 

--- Quote Start ---  

Is it possible to use complex coefficients with the FIR Compiler II? If so, what notation is used to specify this when loading coefficients from a file into the wizard? I've tried i and j, but the wizard is complaining about invalid coefficients. 

--- Quote End ---  

 

 

I know dspbuilder doesn't support complex filter but you can use four real filters and do the complex addition/subtraction manually. 

remember for every tap the following multiplication is needed: 

 

yr = xr.hr - xi.hi 

yi = xr.hi + xi.hr 

 

thus the terms xr.hr becomes one filter for these inputs and the term xi.hi a second filter and so on. Finally you add/subtract the outputs of two pair filters to get real and imag output. 

 

You can alsouse three filters by some trick.
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Altera_Forum
Honored Contributor II
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i don't think FIR II supports complex data paths

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Altera_Forum
Honored Contributor II
105 Views

thanks guys

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