Sonnet User's Guide - Sonnet Software

Sonnet User’s Guide
Normally, if you are using symmetry, ports are placed on the line of symmetry as
pictured below.
Line of Symmetry
Ports are placed
on the line of
symmetry
Ports can be placed off the line of symmetry, but the port placed above the line of
symmetry must have another port equidistant from and below the line of symmetry.
These two ports must also have the same port type, port number and properties.
The basic premise of symmetry is that the voltage at any give point above the
line of symmetry must be equal to the voltage at the corresponding location below
the line of symmetry. Using the same number port, port type and properties ensures
that the voltage is the same at both required points since all ports with the
same number, as pictured below, are electrically connected together.
Port Pair
Port Pair
This circuit has two
sets of ports placed
equidistant from the
line of symmetry.
Note that the
corresponding ports
above and below the
line of symmetry have
the same number.
Line of Symmetry
This circuit violates port
usage with symmetry. The
ports are equidistant from
the line of symmetry but
have different port
numbers so that the
voltage is not equal.
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