Network Analysis and Synthesis - Concise Revision Notes
Q1 + Basics
- Hurwitz Polynomial: All first-column elements of Routh array must be positive. No sign change = stable.
- Causal System: Output depends only on present/past input.
- Port Parameters: h <-> Y <-> Z conversions are common. Remember conversion formulas.
- Laplace Transform of Piecewise: Use u(t-a) shifting and linearity.
- f-cut set: Minimal set of edges that disconnect graph.
- f-tie set: Loops formed by adding a link to a tree.
Unit I: Graph Theory & Thevenin
- Tree: Acyclic subgraph with all nodes.
- Tie-set Matrix: Rows = loops; Columns = branches.
- Cut-set Matrix: Rows = minimal cuts; Columns = branches.
- Thevenin: Open-circuit voltage (Voc), equivalent resistance (Rth).
- Norton: Short-circuit current (Isc), Rn = Voc/Isc.
Unit II: Laplace & Transients
- Laplace of Triangular: Use basic Laplace pairs + shifting.
- Initial Value Theorem: f(0+) = lim(s->infinity)[sF(s)]
- Final Value Theorem: f(infinity) = lim(s->0)[sF(s)] if poles in LHP
- RC Transient: V(t) = V0(1 - e^(-t/RC))
- L inductor: i(t) continuity; C capacitor: v(t) continuity
Unit III: Two-Port Networks
- Z-parameters: V1 = Z11*I1 + Z12*I2, V2 = Z21*I1 + Z22*I2
- Y-parameters: I1 = Y11*V1 + Y12*V2, I2 = Y21*V1 + Y22*V2
- h-parameters: V1 = h11*I1 + h12*V2, I2 = h21*I1 + h22*V2
- ABCD: [V1; I1] = [A B; C D] * [V2; -I2]
- Cascading: ABCD matrices multiply directly
Unit IV: Synthesis & Filters
- PR Function: Real part >= 0 in RHP; pole-zero symmetry; odd-degree numerator.
- Foster I: LC elements in parallel; use partial fraction.
- Cauer I: Use continued division; ladder network.
- Band-pass: Allows mid-range freq; blocks low/high.
- High-pass: Blocks low freq; passes high freq.