x(t) is a band-limited signal with X(jw) = 0 for |W| >Wm.
Then x(t) is uniquely determined by its samples x(nT) = 0,(+,-)[1,2,3]..., if Ws > 2 * Wm, where Ws = (2* pi ) / T
Then if X D [n] = X(nTs) are a collection of samples, then x(t) can be uniquely recovered from its samples if Ts < pi/ Wm