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Time Domain Response

Started by tron_n_telle May 8, 2006
Hi Guys,

I have the stepped frequency data which is in the range 1GHz -3GHz
(201 Frequency steps ; i.e. spacing 10MHz). I am using ifft (MATLAB
command). I am getting 201 points in time domain.

Q: What do the time samples (0-201) correspond to in terms of time
units (seconds)?

Thanks in advance

Tron
Tron-

> I have the stepped frequency data which is in the range 1GHz -3GHz
> (201 Frequency steps ; i.e. spacing 10MHz). I am using ifft (MATLAB
> command). I am getting 201 points in time domain.
>
> Q: What do the time samples (0-201) correspond to in terms of time
> units (seconds)?

The iFFT size does not matter; the sampling rate is determined by the Nyquist rate
which in your case is 2x the usable FFT bandwidth, or 4 GHz. So your time domain
sample period is 0.25 nsec.

But whether your time domain results are an accurate representation -- that's another
question. For one thing, your data has been quantized to large 10 MHz bins, so who
knows what is being missed.

-Jeff