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Consider N section network to find the voltages at each of the N nodes
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Applying Kirchoff's current law to the kth node
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or
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changing index k to k+1, we get
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......................................................................(1)
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This is called a homogenous difference equation.
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Solution of (1) gives
Vk
( )
, the node voltage at the kth node.
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Let
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So,
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where E is called a shift operator.
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Rewriting equation (1)
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or
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Forming the auxiliary equation
m2 - 3 m + 1=0
............................(2)
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Solution of (2) gives two roots
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If we let
we can verify
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Hence, solution to (1) is given by
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..........................................................................(3)
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where A,B are two arbitrary constants.
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