Uniform Distributed RC Model (URC)

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Uniform Distributed RC Model (URC)

The URC model is derived from a model proposed by L. Gertzberrg in 1974. The model is accomplished by a subcircuit type expansion of the URC line into a network of lumped RC segments with internally generated nodes. The RC segments are in a geometric progression, increasing toward the middle of the URC line, with K as a proportionality constant. The number of lumped segments used, if not specified for the URC line device, is determined by the following formula:

The URC line is made up strictly of resistor and capacitor segments unless the ISPERL parameter is given a non-zero value, in which case the capacitors are replaced with reverse biased diodes with a zero-bias junction capacitance equivalent to the capacitance replaced, and with a saturation current of ISPERL amps per meter of transmission line and an optional series resistance equivalent to RSPERL ohms per meter.

name

parameter

units

default

example

area

K

Propagation Constant

-

2

1.2

-

FMAX

Maximum Frequency of interest

Hz

1.0G

6.5Meg

-

RPERL

Resistance per unit length

ohm/m

o1000

10

-

CPERL

Capacitance per unit length

F/m

1.0e015

1pF

-

ISPERL

Saturation Current per unit length

A/m

0

-

-

RSPERL

Diode Resistance per unit length

ohm/m

0

-

-