Hi everyone,

I'm using N9020A MXA Signal Analyzer to make spectrum measurement and collect raw data from instrument memory in order to process them later.

My idea is to use the raw data to reconstruct the signal in the time domain. The way how I'm thinking to do that is make a reverse FFT with the samples that I have collected.

That said my question is how I can decode the sample frequency from setting parameters of SA (I saw that there is a FFT width but I don't understand very well what this parameter is telling me).

Thanks in advance for your help

Best

Pierpaolo

I'm using N9020A MXA Signal Analyzer to make spectrum measurement and collect raw data from instrument memory in order to process them later.

My idea is to use the raw data to reconstruct the signal in the time domain. The way how I'm thinking to do that is make a reverse FFT with the samples that I have collected.

That said my question is how I can decode the sample frequency from setting parameters of SA (I saw that there is a FFT width but I don't understand very well what this parameter is telling me).

Thanks in advance for your help

Best

Pierpaolo

The trace data you are observing is coming from the Swept SA measurement. The trace data contains only the magnitude of the frequency domain and not the phase information. Because of this, you cannot perform an inverse FFT and get the time domain representation of the signal.

You will want to use the IQ Analyzer mode by pressing Mode, IQ Analyzer and then the IQ waveform or Complex Spectrum measurement. Matlab has an FFT function for performing a FFT with the IQ Data. You can then perform a IFFT of this data and get the real time signal back. You will be limited to the bandwidth of the digitizer (10 MHz, 25 MHz or 40 MHz).

Regards -