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Large Number of taps FIR implementation

Altera_Forum
Honored Contributor II
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Hello, 

 

I would like to know if it is possible to implement a 262144-tap FIR filter in a Stratix V? 

The input rate is 200kHz 

The input resolution is 18 bits 

The coefficient resolution is 18 bits. 

 

Thanks for your help and advices! 

 

Cheers!
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Altera_Forum
Honored Contributor II
240 Views

 

--- Quote Start ---  

Hello, 

 

I would like to know if it is possible to implement a 262144-tap FIR filter in a Stratix V? 

The input rate is 200kHz 

The input resolution is 18 bits 

The coefficient resolution is 18 bits. 

 

Thanks for your help and advices! 

 

Cheers! 

--- Quote End ---  

 

 

A bit too drastic. But if you run your clk at 360MHz then you can have time folding of 360/.2 = 1800 hence you will need 

262144/1800 = 146 multipliers
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Altera_Forum
Honored Contributor II
240 Views

Thanks for the tip!

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Altera_Forum
Honored Contributor II
240 Views

 

--- Quote Start ---  

Thanks for the tip! 

--- Quote End ---  

 

 

if your fir is symmetric you can reduce by half by pre-adding then multiply.  

You will need many accumulators. So not a big price for such a huge filter which truely is "Mother of all Filters"
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Altera_Forum
Honored Contributor II
240 Views

 

--- Quote Start ---  

 

I would like to know if it is possible to implement a 262144-tap FIR filter in a Stratix V? 

The input rate is 200kHz 

The input resolution is 18 bits 

The coefficient resolution is 18 bits. 

 

--- Quote End ---  

 

This is probably the wrong question. If you have such a huge number of taps, then you must have a very fast transition band, so the correct question is probably something like ... "how do I filter my wide bandwidth signal to narrow bandwidth? 

 

If you could describe what your filter is supposed to do in terms of input sample-rate and bandwidth, and output sample-rate and bandwidth, members of the forum can help point you in the right direction. Chances are you need a filter followed by decimation, in which case you can eliminate some of the calculations, and make an efficient filter. 

 

Have you read any books on filtering to determine your design? 

 

Cheers, 

Dave
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