# Applicability of Fourier transform to periodic signals? [duplicate]

Can we use Fourier Transform for periodic signals or only we can use fourier series with periodic signals? I am asking this question because I read on page 301 of alex palamides as shown highlighted in attached photo

• It's applicable, but you get Dirac deltas as a result. This raises many mathematical issues and some authors prefer to avoid them. IMO, the FT of a periodic signal doesn't add anything meaningful that is not contained in its FS .
– MBaz
May 12 '19 at 17:44
• This answer shows how the Fourier transform of a periodic signal is computed (from its Fourier series coefficients). May 12 '19 at 17:56