Artificial transmission line

In telecommunications, an artificial transmission line is a two-port electrical network that has the characteristic impedance, transmission time delay, phase shift, or other parameter(s) of a real transmission line.

It can be used to simulate a real transmission line in one or more of these respects.

[1] Early artificial lines were used in telephony research and took the form of a cascade of lattice phase equalisers to provide the necessary delay.

The lattice phase circuit was invented by Otto Zobel in the 1920s.

[2][3]

Schematic of an artificial telephone line section for 6000 feet of 24 gauge twisted pair. L1 and L2 are effectively in series giving 1.12 mH of series inductance.