The length of the line may be expressed in either of two forms. The transmission delay, TD, may be specified directly (as TD=10ns, for example). Alternatively, a frequency F may be given, together with NL, the normalized electrical length of the transmission line with respect to the wavelength in the line at the frequency F. If a frequency is specified but NL is omitted, 0.25 is assumed (that is, the frequency is assumed to be the quarter-wave frequency). Note that although both forms for expressing the line length are indicated as optional, one of the two must be specified.
A lossy transmission line with zero loss may be more accurate than the lossless transmission line due to implementation details.
Parameters
| Parameter | Description | Units | |
|---|---|---|---|
| Z0 | Characteristic impedance. | Ohms | |
| TD | Transmission delay. | seconds | |
| F | Frequency for NL. | Hz | |
| NL | Relative wavelength. | 0.25 | |
| IC | initial condition. Voltage and current at each of the transmission line ports. (VA,IA,VB,IB) |