Avoiding crosstalk in multiconductor TEM waveguides

Abstract

Guided TEM waves have been usually investigated between 2 conductors, but there are many cases which require the analysis of TEM waves guided by many conductors, like flat cables, high frequency polyphase transmission lines, etc. In a previous work I developed a methodology for multiconductor TEM waves, which is in many senses a generalization of the 2 conductors case, but also emphasizes new properties. This work uses the multiconductor TEM formalism to analyze the crosstalk in flat cables, and suggests a method to overcome this crosstalk. It is to be mentioned that by overcoming the crosstalk, one increases the transferred information rate.

Transmission of the maximum number of signals through a multiconductor transmission line without crosstalk or return loss: theory and simulation

“…Now using (50) and (51) with ε r = 1 we obtain the ABCD matrix for any frequency, and using it in (59) and (58) with R = 50 Ω we obtained the S matrix for any frequency and compared them to the S matrices obtained from simulation. The difference between the analytic solution and simulation is around 0.5%, so that the simulation validates the theory in [1][2][3].…”

“…One remark that MTL cannot be matched exactly by individual loads between signals [1][2][3][4][5], unless the differential lines would be mutually isolated. The typical crosstalk of around −20 dB [6] shows that they are not isolated, and hence some return loss must exist.…”

Analysis of lossy multiconductor transmission lines and application of a crosstalk cancelling algorithm

“…use differential signals between pairs of conductors, the application of such an algorithm has the potential to roughly double the information rate. In addition, the usage of differential signals does not allow a perfect match of the MTL [3–10].…”