Radiated Emissions from PCBs with Double MR Before and after Failure

In this paper, experimental study to assess the radiated emissions and the susceptibility of circuits with double modal reservation (MR) is performed. A special PCB prototype was manufactured to be used with a classical TEM-cell to measure the S-parameters up to 2 GHz that are used to calculate the field strength magnitudes from the PCB at different compensation of boundary conditions. The PCB with double MR was investigated not only under ideal operating conditions, but also under the worst failure conditions at the transmission line ends. The effectiveness of applying the double MR in PCBs manufacturing even after failures was evaluated. The optimal way to choose the conductors of PCBs with double MR regarding to the radiation levels and susceptibility to radiation was revealed.