“…In particular, they affect more markedly high frequency components, causing a strong reduction in pulse equivalent bandwidth (this quantity is defined as the standard deviation of the pulse evaluated in the frequency domain [2,4]). As an example, in power cables, PD pulse equivalent bandwidth can drop from the GHz range to a few tens of MHz in about 100 meters [5,6]. As a consequence, detectors able to evaluate PD pulse frequency content (which can be quantified, e.g., through the equivalent bandwidth concept) can provide information concerning PD source location and allow to separate contributions in the PD pattern due to multiple sources.…”