An extension of Szász´s theorem for random signal representation

Szász´s theorem is extended to the exponential representation of random signals. It is shown that for the class of random processes with square integrable autocorrelation functions R(t, τ), the set {e^skt} is complete if and only if this set satisfies Szász´s condition. The result also holds for the class of random processes having absolutely integrable R(t, t).