18
Let x(t) represent a band limited signal so that X(j w) = 0 for w < |wn|. if ws > 2wn. where ws = 2*p/t is the sampling frequency. Then x(t) is uniquely determined by its samples. x(n* t). The minimum sampling frequency is often referred to ahttps://docs.google.com/Doc? docid=0AevSy28gpBDkZGRtMmJ2dnFfMzRtZGJoN2t3dg&hl=ens the nyquist sampling rate or nyquist rate. Under sampling: When the sampling rate is less than the nyquist rate, there is overlap of the frequency componen ts and the higher frequency components and the other higher frequency terms of the continuous time signals appear in the low frequency region. This is referred to as aliasing. Over sampling: If the sampling rate is greater then there is a lot of redundancy in the d iscrete time signal. This is referred to as over sampling. Matlab Program: %to verify sampling theoreom %critical sampling
