calculate SNR and watch a binary file

[Francesco Potorti`]

>>> filename = "spectrum.m";
>>> fid = fopen (filename, "r");
>>> [val, count] = fread (fid, 100, "uchar", "native")
>>> fclose(fid);

>>> As i know my Spectrum Analyser produces I/Q Signals, so there should be
>>> 2*16 bit values. Each 16 bit value is complex.
>> 
>> What you wrote is either a typo or I do not understand it.  I suppose
>> you meant that each complex value is written as two 16 bit numbers.
>> If this is the case, do not use "uchar" but "int16".  Then try and see
>> if you get the correct numbers, probably the real and complex parts of
>> each sample.  If not, try to experiment and guess how the numbers are
>> written to the file.  Or else try to find some documentation on it :)

>in my Spectrum there is an unknown peak in the middle of the FFT-Plot
>which exists every time. I think it will be created as byproduct
>of a CIC decimation(Digital Down Converter) in my analyser.
>Therefor i want to manipulate this complex values, but didn't know how
>to ?

Have you applied my suggestions above?

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Francesco Potortì (ricercatore)        Voice: +39 050 315 3058 (op.2111)
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