Circuit => Ref. Planes/Cal. Length

Project Editor Menu - Circuit Menu - Reference Planes/Calibration Lengths dialog box

Em has an automatic de-embedding capability. When invoked, em removes the port discontinuity and a desired length of transmission line, moving the reference plane into the interior of the box. The reference planes used for de-embedding are set with this option. One reference plane length per box side may be specified.

Parameters => Ref. Planes/Cal. Length also allows you to specify the calibration length used for de-embedding. A box side has a reference plane or a calibration length, but not both. Please note that it is possible for the calibration length to be greater than the box length.

NOTE:            This dialog box is used only for standard ports. Setting Reference planes/Calibration lengths for an auto-grounded port must be done in the Port Properties dialog box.

When you select Parameters => Ref. Planes/Cal. Length, the Reference Planes/Calibration Lengths dialog box is opened.

Box-wall List: Each of the four box walls are listed here. The radio buttons below the list affect whichever box wall is presently selected. The reference plane extends from the selected box wall to the end point specified in the radio group below.

Linked Radio Button: Selecting this radio button links the end of the reference plane to a point on a polygon. As that point on the polygon moves, as part of a reshape or a new value for a parameter, the length of the reference plane also changes. After selecting this radio button, you click on Mouse button, then click on the point in your circuit to which you wish to link the reference plane.

Fixed Radio Button: Selecting this radio button allows you to assign a fixed length to the reference plane. After selecting this radio button, you may set the length one of two ways. You can enter a length in the text entry box which was enabled when you selected this option. Alternately, you may click on the Mouse button, then click at the place in your circuit to which you wish to the reference plane to extend.

None Radio Button: Selecting this radio button means that no reference plane is used at all. Only the port discontinuity is de-embedded. If you wish to use a calibration length for that box wall click on the Used fixed cal. length checkbox and enter the calibration length in the text entry box that is enabled by selecting the checkbox.

The project editor may change the reference plane slightly so that it is aligned with the edge of a cell. The actual position is indicated with a short vertical line at the actual reference plane location. Linked reference planes are indicated by the outline of an arrow while fixed length reference planes are indicated by solid arrows.

To remove a reference plane, click on the None radio button and set the Used fixed cal. length checkbox to off. There is only one reference plane or calibration length per box side. The same reference plane is used on all ports on all levels on that side of the box.