Suppression effect of the emission from printed circuit board using magnetic absorber located along microstrip line

The effect of suppressing electromagnetic emission from a printed circuit board (PCB) with a microstrip line by using a magnetic absorber located along the microstrip line is investigated. On calculation, a ferrite plate with the Debey dispersion is used as a magnetic absorber. The PCB consists of an infinite ground plane, dielectric substrate and a microstrip line terminated with an open, short or 50 /spl Omega/ load. The frequency dependent finite different time domain (FD-FDTD) method is used for the numerical analysis. The calculated results suggest that the suppression effect is achieved by a magnetic absorber is placed at a large magnetic field intensity. The analysis results are confirmed with the measured results using another magnetic absorber.