# Eq cycle results

A complex discrete-time signal x [ n ] {\displaystyle x[n]} is a real signal ( if x [ n ] ∈ R ∀ n ∈ N {\displaystyle x[n]\in \mathbb {R} \quad \forall n\in \mathbb {N} } ) if and only if its DTFT X 2 π ( ω ) {\displaystyle X_{2\pi }(\omega )} is conjugate symmetric.