Automated near Field Spatial Mapping for Multilayer Ground Split Noise Detection
Automated near field spatial mapping identifies hidden split-plane return current loops and isolates board-level electromagnetic noise sources before EMI certification.
Far Field Transformation
Predictive Modeling
A mathematical calculation predicts the electromagnetic radiation patterns at a great distance from a source based on measurements taken in the immediate vicinity of the circuit. Developers apply far field transformation to convert data from near field scanners into the formats required for regulatory compliance testing. The method avoids the need for massive test chambers during the early stages of design.
Computational Method
The algorithm uses the phase and amplitude of measured electric and magnetic fields to solve Maxwell equations for a distant point. During far field transformation, the software integrates the tangential field components over a closed surface surrounding the device under test. The integration process accounts for the phase shifts and interference patterns that emerge as waves propagate away from the source.
The resulting data provides a polar plot of the radiation intensity in all directions.
Result Accuracy
Reliability of the prediction depends on the density and precision of the initial near field measurements. Errors in the far field transformation arise if the scan area is too small or if the probe height varies during data collection. A valid model provides a clear view of the peak emission directions and the overall radiated power.