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Fields and Waves. Lesson 1.4. LOSSY TRANSMISSION LINES. Lossless/Lossy Models of TL. Lossless Model of TL:. Loss effects due to Resistances:. Lossy Model of TL:. R - resistance of conductors. G - conductivity of insulators. - both are ideally small. , if constant cross-section. Outer.
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Fields and Waves Lesson 1.4 LOSSY TRANSMISSION LINES Darryl Michael/GE CRD
Lossless/Lossy Models of TL Lossless Model of TL: Loss effects due to Resistances: Lossy Model of TL: R - resistance of conductors G - conductivity of insulators - both are ideally small
, if constant cross-section Outer Inner Estimation of R On a per meter basis, because inner and outer conductors are in series • At high frequencies, not all the copper is used for conducting (see Lesson 3.1) • Current only flows in outer portion due to skin depth effects
I From Electrostatics, Also, Estimation of G The 1/G component represents radial current flow, due to small s of insulator • the cross-sectional area is not constant Estimation of G: Do Problem 1a &1b
For Lossless system, Rc represents I V Effects on Zc - Characteristic Impedance Replace j.w.l with r + j.w.l Replace j.w.c with g + j.w.c Characteristic Impedance
Attenuation Factor For lossless systems: For lossy systems: The phasors have the factor: Attenuation/loss factor due to resistance