And because the spectrum of a discrete time signal, this exact spectrum will periodically repeat if we prolonged the frequency larger over and above $f_s$ this sort of the spectrum revealed is additionally the same spectrum in each frequency band from $nf_s$ to $(n+one)f_s$ for any integer $n$. a : https://pgsector14gurugram.blogspot.com/2025/07/book-affordable-1-rk-for-rent-in.html