How to make the fft of a signal while receiving it?

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Hello everyone. Thanks for reading. I need some help to solve a problem that i have.
I am digitalizing a signal through a dsPic which samples de signal at 8000hz, and then send's them to the Pc where i receive then with matlab to make the fft. I receive 8000 samples and then i do the fft, so, i can do a fft once per second.
t = 0:1:7999; % time Fs = 8000; % sample frec Ts = 1/Fs; % period y = sin(2*pi*1500*t*Ts); % imagine this signal is the received one Y=abs(fftshift(fft(y)))/4000; stem(0:Fs/2-1,Y(Fs/2+1:end))
What I would like to do, if possible, is to increse the refresh rate of the fft. So i thought i would do the fft with the first 20 bytes received, and then with the following 20 and so on, until the 8000 slot fifo buffer is completed.
Thats it, I hope you can understad what I mean. Thanks!
Gonzalo

Answers (1)

Chibuzo Nnonyelu
Chibuzo Nnonyelu on 1 Mar 2013
I recommend you add timer to your code. Let the timer re-initiate the same process after the specified interval.
t = timer('TimerFcn','_your_sampling_function_([var])',... 'StartDelay',0.5,'ExecutionMode','fixedDelay',... 'BusyMode','drop','Period',1); % start(t); % stop(t); % delete(t);
Read more on this 'timer' function.

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