[信息与通信]第二章传输线理论.pdf

Chapter 2 Transmission Line Theory 2.1 The lumped-element circuit model for a transmission line transmission line or telegrapher equation, traveling wave solution 2.3 The terminated lossless transmission line Zin, Γ, VSWR time-average power flow 2.4 The Smith chart Zin-plot conformal mapped on Γ-plot 2.5 The quarter-wave transformer frequency response, TDR 2.6 Generator and load mismatches impedance match, conjugate match 2.7 Lossy transmission lines low loss line, distortionless line perturbation method 2- 1 路 路 2.1 The lumped-element circuit model for a transmission line • Transmission line equation TEM lines: coaxial line, parallel line and stripline i(z, t) i(z, t) i(z+∆z, t) + + + R∆z L∆z - v(z, t) z v(z, t) G∆z C∆z v(z+∆z, t) - - ∆z ∆z R, L: conductor resistance, inductance/unit length (series elements) G, C: dielectric conductance, capacitance/unit length (parallel elements) ∂v ( z , t ) ∂i(z , t) =−Ri (z , t) −L ∂z ∂t ( , ) ( , ) KVL, KCL ⇒ ∂i z t ∂v z t ( , ) =−Gv z t −C ∂z ∂t time-domain transmission line, or telegrapher eq