New technical paper: Intra-Pair skew: About wave propagation in screened single pair27.10.2023
We show that intra-pair skew cannot be properly defined on a single As S21 represents the signal propagation in one wire of the pair, it is
screened pair, as the signal launched in a single wire does not expected to be a smoothly decreasing curve. However,
propagate as such along the pair due to inter-wire coupling. measurement does not show the expected behaviour (cf. Figure 1).
Measured S21 is a “bumped” curve with dips falling to zero (or close to) at regular frequency intervals.
This coupling and propagation behaviour is illustrated using an analogy with the coupled pendulum system.
The measurement results can be described using a combination of the common and differential propagation modes. This is confirmed by TDR results of signal propagation.