5.2 System Representation with signal flow-graph o The computational algorithm of an lti digital filter can be conveniently represented in block diagram form using the basic building blocks representing the unit delay, the multiplier, the adder, and the pick-off nodes5.2 System Representation with signal flow-graph  The computational algorithm of an LTI digital filter can be conveniently represented in block diagram form using the basic building blocks representing the unit delay, the multiplier, the adder, and the pick-off nodes