I wrote a python program to generate OFDM packets (i.e. the IQ samples) with a custom payload to, for example, be transmitted via an SDR. After mapping the chunk of bits corresponding to one ofdm symbol to a constellation mapping (e.g. 64QAM), I perform the IFFT (using numpy.fft.ifft) and add the 16-sample cyclic prefix. In the IEEE standard, the resulting 80-sample time snippet is multiplied by a windowing function (x0.5 for first and last value). However, when I test the whole thing and perform FFT on the 64-sample snipped again the whole mapping has a rather large error.
Now I've read in the standard that symbols are appended one after another with one sample overlap, which I am currently not doing, so I guess there lies my mistake. If I append them with an overlap of one though, I would end up with a wrong overal sample count, wouldn't i? ( i.e. $80 * nSymbols - nSymbols$ instead of $80 * nSymbols$)
Thanks for every hint! Cheers Lucas