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Altera_Forum
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16 years ago

Bits to keep: output FIR

Hi everybody, I’m working with a Stratix II and I generate a FIR Raised Cosine with DSP builder Megafunction (Matlab/Simulink). The output bits are 22 bits, but I can keep only 1...
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Altera_Forum
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16 years ago

Thanks Kaz!

OUTPUT = 22 (14-22=8)

I have 12 bit (cpl 2) input then => 2^(12-1)-1 = 2.047

The sum coeffiecients (101) = 0,98707...

2.047*0,98707 = 2.020,5420... <- the max value of convolution (right?)

then 11 bit

bits to keep = 14

LSB = 0

MSB = 8 TRUNCATE

Is correct?

thank a lot of!!

Fabio