Comparative analysis on field-induced electromagnetic shielding material with two kinds of test device

Field-induced electromagnetic shielding material show an abrupt decrease of resistance when external electromagnetic field exceeds a threshold value, the material will occur metal-insulator transition phenomena in the nanosecond time, Owing to threshold value was so high that traditional static test method and low-voltage dynamic test can not satisfy test require. According impedance matching principle and time domain reflection, two kinds of dynamic test device are designed, the working principle of them are compared and analyzed, pulsed measurement show that the test device based on time domain reflection is more correct and directly.