Unformatted text preview: grams & Signal-Flow Graphs ECE382 13 / 31 Signal Flow Graphs - Definitions
Loop a loop is a closed path, which originates and terminates on the same node, and along the path no node is met twice. Self-loop is a closed loop consisting of a single branch and single node. Loop gain is the product of the branch transmittances of a loop Forward path is a path from an input node to an output node that does not cross any nodes more than once. Forward path gain is the product of the branch transmittance of a forward path. Nontouching loops loops that do not possess any common nodes.
C. S. George Lee (Purdue Univ.) Block Diagrams & Signal-Flow Graphs ECE382 14 / 31 Signal Flow Graph Notation & Definition Example
A42 A33 Input node: X1 A21 A54 A32 Output node: X5 X4 X5 X2 A43 X3 X1 Loops: X2 to X3 to X2 (closed loop: L1 ) A23 A44 X3 to X3 and X4 to X4 (self loops: L2 & L3 ) Paths: X1 to X2 to X3 to X4 to X5 (forward path: P1 ) X1 to X2 to X4 to X5 (forward path: P2 ) Loop Gain: X2 X3 X2 : L1 = A32 A23 X3 X3 : L2 = A33 and X4 X4 : L + 3 = A44 Path Gain: X1 X2 X3 X4 X5 : P1 = A21 A32 A43 A54 X1 X2 X4 X5 : P2 = A21 A42 A54 Two non-touching loops: L1 and L2 ; L2 and L3 Two non-touching loop gain: L1 L2 = A32 A23 A33 ; L2 L3 = A33 A44
C. S. George Lee (Purdue Univ.) Block Diagrams &...
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This note was uploaded on 02/05/2012 for the course ECE 382 taught by Professor Staff during the Fall '08 term at Purdue.
- Fall '08