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Some general properties of z-transforms

Linearity

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where the ROC is the region where both tex2html_wrap_inline548 and tex2html_wrap_inline550 converge.

Example - the 2-sided exponential sequence

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Using linearity and transforms found above :

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The ROC is |z|>|a| for the first term and |z|<|b| for the second. Thus there is no ROC unless |b|>|a| .

Shifting property of the transform
Suppose tex2html_wrap_inline558

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Substitute p=n-m so n=m+p :

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Multiplication by n and derivatives in z

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Keith Jones
Tue Oct 27 09:51:00 EST 1998