[SOLVED] FSK demodulation poblem.

[hamidkavianathar]

I want to simulate the FSK demodulator. these are my parameters:
F1 = 16.5 kHz - 64 Hz, F2 = 16.5 kHz + 64 Hz.
as the difference between F1 and F2 is very small, I can't extract my data correctly. Can someone guide me?
thanks.

 

[FvM]

How are you extracting the data?

 

[hamidkavianathar]

How are you extracting the data?

thanks for the comment. this is my algorithm:


I have simulated it in MATLAB/simulink environment.

 

[FvM]

What's the timing of the accumulator control signals?

Summing quadrature magnitudes doesn't give the absolute magnitude, need to calculate squared sum.

 

[hamidkavianathar]

What's the timing of the accumulator control signals?
Summing quadrature magnitudes doesn't give the absolute magnitude, need to calculate squared sum.

thanks for your attention and your help.
I think calculated the sum in this block diagram:


and I have illustrated my signals in this image:


in the above image F1 = 16564Hz , F2 = 1643 Hz. the difference between F1 and F2 is very high, but I couldn't retrieve my data.

 

[FvM]

Squaring the product before accumulator can't be right.

 

[hamidkavianathar]

Squaring the product before accumulator can't be right.

thank you. You helped me very much. I have no idea how I can thank you.:clap:
you're right. I modified it and it according what you said and now it works very well.
I want to ask you another question, do you know how i can make it robuster? I have not consider the distortions.