Multiple transmission lines

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Discussion Overview

The discussion revolves around the analysis of multiple transmission lines connected to a source with internal impedance. Participants explore how to analyze reflections and draw bounce diagrams, referencing a specific patent related to high-speed data processing systems.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires about analyzing reflections and drawing bounce diagrams for a source with 20 ohms internal impedance connected to multiple transmission lines of similar impedance but varying lengths.
  • Another participant suggests sending a short pulse to observe returning signals, indicating that the velocity factor of the lines is necessary for calculating line length. They note that continuous signals could lead to complex interactions and standing waves.
  • A third participant paraphrases the patent, stating it describes the multiple lines behaving like a lumped capacitor and inductor, expressing confusion about this concept.
  • A follow-up question asks if the previous information was helpful, indicating a desire for clarification or further discussion.

Areas of Agreement / Disagreement

Participants express uncertainty regarding the implications of the patent and how the transmission lines function together. There is no consensus on the analysis methods or the interpretation of the patent's claims.

Contextual Notes

Participants mention the need for specific information such as the velocity factor of the lines and the absence of diagrams in the patent, which may limit understanding of the described concepts.

Who May Find This Useful

This discussion may be useful for individuals interested in transmission line theory, signal processing, and the implications of patents in high-speed data systems.

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If a source which has internal impedance 20 ohms is connected to multiple transmission lines of impedance somewhat equal to 20 ohms, which vary in length(maybe from 1" thru 8").
How do I analyze the reflections/draw the bounce diagrams.
According to a patent - http://www.docstoc.com/docs/5001518...rocessing-System---Patent-5696667#viewer-area
this is supposed to work. How? I can't figure out.
 
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Assuming you know the velocity factor of the lines, you could send a very short pulse and observe the returning pulse. You could then calculate the length of the line from the speed, if this is what you wanted to do.

If your signal source was continuous, then the returning pulse would interact with the later incoming waves and may form a standing wave if the line was resonant.

If you had multiple lines all connected in parallel and a continuous source, the result would be a mess of signals. A single pulse would give multiple reflections, but you would not know which of the parallel lines was responsible for each pulse.

What do you think that patent was describing? My copy of it had no diagrams, so it was difficult to see what was being described.
 
To paraphrase, the patent says, the multiple lines make the tx line like a lumped capacitor and inductor.
I don't understand how this happens.
Try pat2pdf.org to download a copy.
The patent number is 569xxx7
x=6
 
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