RF-00
Course overview

Distributed circuits & transmission lines from Maxwell

Build transmission-line theory as a controlled reduction of electromagnetic propagation: first local voltage/current and distributed storage/loss, then telegrapher equations, characteristic impedance, propagation constant and line power.

5/5available
Prerequisites
  • EM-04 — electromagnetic waves & power
  • AC-02 — frequency response
  • Basic differential calculus
By the end of this course
  • Decide when an interconnect must be modeled as a transmission line.
  • Derive distributed equations from an infinitesimal line element.
  • Connect R′,L′,G′,C′ to fields, loss and stored energy.
  • Obtain γ and Z₀ and interpret propagation, attenuation and power.
Syllabus

Distributed circuits & transmission lines from Maxwell

Build transmission-line theory as a controlled reduction of electromagnetic propagation: first local voltage/current and distributed storage/loss, then telegrapher equations, characteristic impedance, propagation constant and line power.

  1. 01

    From lumped circuits to distributed lines

    Decide when propagation delay matters, define voltage and current on a two-conductor line, connect fields to per-unit-length R′, L′, G′ and C′, derive the infinitesimal line element and obtain the time-domain telegrapher equations from local KVL/KCL without treating them as memorized RF formulas.

    180–230 min · Advanced · available
    →
  2. 02

    Solve the telegrapher equations

    Move the time-domain line equations into AoN phasor form, define the series impedance and shunt admittance per unit length, decouple the system, derive γ²=Z′Y′, interpret γ=α+jβ, and obtain forward/backward voltage and current waves with the correct reverse-current sign.

    180–230 min · Advanced · available
    →
  3. 03

    Characteristic impedance

    Promote the forward-wave voltage/current ratio to the exact lossy characteristic impedance Z₀=√(Z′/Y′), tie its branch to passive γ, recover the lossless limit, connect Z₀ to geometry through a TEM coax example, derive the low-loss approximation and use the backward-current sign to audit transported power.

    190–245 min · Advanced · available
    →
  4. 04

    Propagation constant, loss & distortion

    Open γ=α+jβ into exact attenuation and phase, derive the low-loss conductor/dielectric contributions, convert nepers to decibels, distinguish phase and group delay, prove the Heaviside distortionless condition and delimit the frequency-independent RLGC model.

    190–245 min · Advanced · available
    →
  5. 05

    Transmission-line power flow

    Derive instantaneous and harmonic line power from the fixed voltage/current references, preserve the peak-phasor factor 1/2, distinguish forward/backward signed power, obtain the exact local RLGC loss balance, recover the Poynting-flux identity for a TEM line, connect power to stored energy and introduce a safe real-Z₀ normalization before later scattering theory.

    200–255 min · Advanced · available
    →
Reference backbone

References

The course uses field theory and microwave texts together so that line quantities retain their electromagnetic meaning.

01
D. M. Pozar, Microwave Engineering, 4th ed., Ch. 2

Transmission-line model, telegrapher equations, propagation constant, characteristic impedance and line power.

02
R. E. Collin, Foundations for Microwave Engineering, 2nd ed., Ch. 3

Distributed-line theory, field interpretation and rigorous transmission-line limits.

03
S. Ramo, J. Whinnery & T. Van Duzer, Fields and Waves in Communication Electronics, 3rd ed.

Connection between electromagnetic fields, two-conductor lines, stored energy and distributed parameters.