The Far-field Estimation for Microstrip Line Based on Near-field Scanning

Far-field test of device is a very significant way for electromagnetic compatibility (EMC) diagnose. And the far-field emission estimation typically requires the accurate information of noise source which usually may not be feasible. Microstrip line is one of the main radiation sources of printed circuit board (PCB), and the surface current on which causes the far-field emission. An efficient numerical equivalent source model based on near-field scanning is proposed in this paper. The near-field tangential component of magnetic field is measured by a magnetic probe to obtain an equivalent source. And the far-field estimation is calculated by this numerical source model. It will save a lot of time compared with the full-wave simulation and far-field test in anechoic chamber.