Calulate the sample time in ifft

I have a vector with 1601 complex numbers measured in a frequency range of 3GHz. I want to calculate the ifft of that signal. How can I obtain the sample time?

Thank you

[Adam]

You don't seem to have enough information to do so.

[Ced]

Adam is right, but maybe you have more information than you might think. What is this 3Ghz limit? Is this the Nyquist frequency? If yes, you can get the sampling time from that.

Also, is your frequency data given in equidistant frequency intervals? Do you know how it was obtained? If you know that the fft was done with all the data points and you know how many points were used, you can infer the sampling time from the frequency spacing. The idea is again that your frequency range will be split into N/2 frequency points (+-1 depending on odd/even) from 0 to the nyquist frequency.