Block diagram algebra for sampled data systems

Block Diagram Algebra for Sampled Data Systems 

A comparison of equations 7.209 and 7.210 establishes that, in order to derive the pulse transfer function G (s) from the continuous transfer function G(s), we must star both sides of equation 7.209 by writing  

Two further common sampled data configurations are illustrated in Fig. 7.90. From Fig. 7.90a  

in this case, the transfer function of the two blocks in series is  

The essential difference between equations 7.217 and 7.218 is illustrated in the following example. 

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