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Altera_Forum
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17 years ago

Low Pass IIR filter using cyclone II FPGA

Hi everyone, I hava a task to implement low pass iir filter on cyclone II FPGA. The parameters of filter are the following: fp=5kHz; pass band frequency fs=8kHz; stop band frequency Fs=44k...
Altera_Forum's avatar
Altera_Forum
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17 years ago

1 . If your N bits ADC is not two's complement:

add to the conversion result 2^(N-1) in order to convert to signed.

2. multiply de x(n-i) sample with filter coefficient, result will be : N + N_coeff

the simplest way to round is with an N_frac bits rigth arithmetic shifting. N_frac es the fractional part length.