5.1 Introduce o a structural representation using interconnected basic building blocks is the first step in the hardware or software implementation of an lti digital filter o The structural representation provides the relations between some pertinent internal variables with the input and the output that in turn, provides the keys to the implementation5.1 Introduce  A structural representation using interconnected basic building blocks is the first step in the hardware or software implementation of an LTI digital filter.  The structural representation provides the relations between some pertinent internal variables with the input and the output that, in turn, provides the keys to the implementation