Periodic Glass Weave Loading

[Jason]

The purpose of the attached deck is to understand and quantify the dependencies of the glass-weave loading on the trace such as the impact of the glass-weave pitch, width, thickness, proximity on the single-ended line parameters. Specifically, the project is for a 'unit cell' of a single-ended stripline. The unit cell length is dictated by the pitch of the glass bundles. By concatenating many of these unit cells (depending on the trace length), the full glass-weave grid can be approximated. The glass bundles are crudely modeled to have a rectangular cross-section. The glass bundles are all on one layer (i.e. they don't pass under and over each other). For a more realistic model of the geometry of the glass weave see:
viewtopic.php?f=19&t=7

Here is an overview of the parameters:

"trace_width" is the width of the trace.
"planeThickness" is thickness of the upper and lower planes.
"traceThickness" is the thickness of the trace.
"planeWidth" is the width of the upper and lower planes.
"top_trace_dist" and "trace_bottom_dist" control the vertical separation between the trace and the upper and lower planes, respectively.
"bundlepitch" controls the pitch of the glass bundles.
"offset" controls the vertical offset of the trace from the glass bundles.
"scale" is a ratio which dictates the thickness of the glass-weave relative to to the trace-to-plane separation. "1" means the glass-bundles fill 100% of the region vertically from the trace face to the upper or lower plane face.
"ratio" is a ratio which controls the width of the glass-weave. "1" means that 100% of the Z-Y plane is filled with glass. "0.5" means that the glass weave is 50% filled on the Z-Y plane.

The project was used as part of the DesignCon 2010 paper/presentation entitled "Additional Trace Losses due to Glass-Weave Periodic Loading". The paper and presentation material are also included below. Note that this project was used for only a portion of the simulation results; several other simulations environments were used in the paper and presentation.

Project View

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