Transmission Line Model


Idealized Transmission Line Model



Real Transmission Lines





The bottom line is that a transmission line may be represented as a distributed continuum of coupled harmonic oscillators and, thus, excitations on a line propagate as waves! (See our earlier discussion of the modes of coupled oscillators)

                     

(see also the applets Transverse Traveling Wave and Wave Propagation along a Transmission Line as well as the MATLAB simulation TLS)

Transmission line characteristic:

Results of Transmission Line Model Calculations:

the attenuation parameter

where       

the index of refraction or
normalized Inverse phase velocity

the high frequency phase velocity
the characteristic line impedance


Measured Characteristics of Real Transmission Lines:

Characteristics of an open-wire pair

Characteristics of an twisted-wire pair

Attenuation

Velocity

Characteristics of an inductively loaded transmission line (reference)
Attenuation

Velocity

Picture of coil "pot"source

Specifications of common coax cables (reference)

Attenuation

Comparison of the attenuation characteristics of several wire mediums


This page was prepared and is maintained by R. Victor Jones
Comments to: jones@deas.harvard.edu.

Last updated March 9, 2004