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Altera_Forum
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12 years ago

demodulator with altera megafunction

hi, i've to realize a i-q demodulator for low frequencies signals with the classical scheme https://www.alteraforum.com/forum/attachment.php?attachmentid=9034 The input signal is a 1,3H...
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Altera_Forum
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12 years ago

yes both NCO and filter should run at same speed.

assuming your sampling rate is 1KHz, cutoff of 10Hz,attenuation of 60dB at 100Hz then

a possible filter is (in matlab) h = fir1(74,.02);

you will need two such filters for each of I and Q