Coupled LinesStripline coupled meander/straight lines
This type of block implements a folded (meander) stripline coupled with a straight stripline (4 port). This block can be used for distances between adjacent meanders (folds) down to about half the substrate height (Height/10 for a single fold line) and for distances between the two lines down to about Height/2. The number of folds is 0…9. The following figure illustrates the layout.
The reference planes are marked RP1…RP4 in the above diagram. Note, that in order to ease structure definition, strip center lines are used in the above schematic.
The implemented model may consider conductor losses as well as dielectric losses.
The block is characterized by the properties listed below. To modify the values, use the Block Properties – Parameters dialog box. The common substrate properties are defined by a Stripline Reference Block.
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Meander Start Length |
Start length from RP1 to the beginning of the folded line (> Width/2) |
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Meander Stop Length |
Stop length of the folded line to RP2 (> Width/2) |
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Meander Transverse Length |
Transverse length of the folded line (≥ Height/2 + Width) |
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Meander Fold Length |
Fold length of the folded line. The fold length should be ≥ Height/2 + Width for multiple folded lines since the model only considers coupling between adjacent meanders and neglects all other coupling for reasons of efficiency (accuracy reduces if Meander Fold Length < Height/2 + Width). For a single fold, the fold width can be as small as Height/10. |
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Width |
Width of both traces |
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Distance |
Distance between the straight line and the start section of the folded line. The minimum distance should not be considerably smaller than Height/2 else coupling at bends may become noticeable. |
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Number Of Folds |
Number of folds of the folded line (0…9). A value of 0 describes a simple strip displacement (two 90° bends). |
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Fold Direction |
Direction of the first fold of the folded line (to the left in the figure above). The line can either start with an inward turn (towards the other line), or an outward turn (away from the other line). Note that a change of this parameter from Outward to Inward may result in overlapping strips (if the distance is too small). |
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Mitered Bends |
Switch that determines the model used for all bends: Either mitered bends with a 50% chamfer or full bends. |
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Straight Line Length |
Length of the straight line |
The properties listed above and the substrate properties of the reference block define the electrical behaviour of the block. The layout view uses another set of layout properties. These properties define the position of the block in the layout view. The electrical behaviour of the block does not depend on these properties.
See also
Block Overview, Stripline Reference Block, Layout Properties