Theoretical and experimental quantitative characterization of the near-fields of printed circuit board interconnection structures

Anticipating Common-Mode Conducted Emission of DC-DC Converter from Electric Near-Field Scan

“…Locally, the displacement current density JD is related to the electric field E according to (1) where ε0 is the dielectric permittivity. In harmonic regime, if the electric-field that crosses a given surface S is measured, an equivalent current ID can be determined (2).…”

“…NFS is considered as a powerful method to identify root-cause of EMC problems at printed-circuit board (PCB) or integrated circuit (IC) level, as demonstrated in numerous publications. For example, it was used for the characterization of emission at PCB [2] and IC level [3] [4], risk of near-field coupling above toroidal inductance [5] [6], HF current reconstruction [7], RF [8] and ESD immunity [9] [10].…”

Closed-Form Expressions of Electric and Magnetic Near-Fields for the Calibration of Near-Field Probes

“…It consists in extracting the response of the NFP to the incoming field, in order to reconstruct the actual field distribution. In its simplest or standard form, the calibration process consists in extracting the sensitivity of the probe, assuming the probe has an infinitesimal small size [6]. The probe sensitivity is given by a figure called performance factor (PF), which is the ratio between the induced voltage at the probe terminal and the incoming E or H-field on the probe.…”

Calibration of the loop probe for the near-field measurement

“…Formulations of probe-corrected planar near-field scanning in both frequency and time domains have been proposed by Hansen and Yaghjian [11]. A probe calibration is performed by means of a TEM-cell measurement and the use of near-field probes is also characterized in a theoretical way by [12]. The influence of the measurement probe on the evaluation of the farand near-field of an EM source is characterized in [13].…”