9.3 Upsampling (or Interpolation)
The upsampling (or interpolation) is the process of increasing the samples ofthe discrete time signal.
Let, x(n) = Discrete time signal
I = Sampling rate multiplication factor (and I is an integer).
Now, x(n/I). Upsampled version of x(n).
The device the which perform the process of upsampling is called upsampler
( or inepolaton). Symbolically, the upsampler can be represented as shown in fig 9.5.