Re: a mini question about the "sample sheme" of OFDM

This isn't quite right. Keep in mind that frequencies that appear to
be beyond the Nyquist frequency will end up wrapping (aliasing) around
into the -ve frequencies. So...

.........................N/2........................: 0 + (N/2-1)/(N*T)
Hz
.......................N/2+1......................: 0 - (N/2)/(N*T) Hz
....
.........................N..........................: 0 - 1/(N*T) Hz

Also, the OFDM symbol period will be N*T + M*T, where M represents the
number of samples used for the cyclic prefix and suffix.

.

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