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Altera_Forum's avatar
Altera_Forum
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11 years ago

fir filter for fsk demodulator

Hi, i've realized an i_q demodulator for fsk message. The frequencies for the 0 and for the 1 are spaced 400Hz; the baud rate is up 200baud. The frequencies are in the audio range (for example F...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

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the sample rate i choose is 200KHz and the highest frequencies for the fsk are around 20KHz...

What about the solution of CIC?

What about the solution of IIR?

Let me know...

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I am lost with your figures.Let us restart:

adc signal

sampling rate = 200KHz

f0 = 4.050KHz

f1 = 4.450KHz

what is that 20KHz?

baud = 200, can't be

IQ demod outputs:

IQ demodulator downconverts to what values for f0,f1

you will need to filter the second sideband on each of I and Q after downconversion. So you need to tell us what is f0,f1 after IQ demod and what is sampling rate.