# Find cepstrum of a function with dirac function

$$x[n] = d[n] + a\cdot d[n − N_p]\ ,\ \ |a| < 1$$

I need the complex and real cepstrum of this function as well as what would happen for $N=N_p/6$ for the DFT approximation $$x_p[n] = \frac{1}{N} \sum_{n=0}^{N-1}\log(X[k]) e^{j2kn/N}$$.

It is a school assignment in which I am missing a lo of the functions required to proceed so also any info you can link is greatly appreciated.

• yes you are right I apologise – siegfried Apr 25 '18 at 12:16
• thanks for fixing that! I'm deleting that now obsolete comment :) – Marcus Müller Apr 25 '18 at 12:30