Shielding Effectiveness of a PC Case Using Three-Axis Electro-optic Sensors

This paper presents a measurement method for the shielding effectiveness (SE) of a personal computer (PC) case using three-axis electrooptic sensors and a vector network analyzer (VNA). The SE is obtained by taking the difference between the logarithmic values of the ratios of transmitted power to the input power for conditions with and without the PC case. The SE measurements versus the incident angle and polarization of incident electromagnetic fields are performed in a fully anechoic chamber (FAC) in the frequency range of 1 GHz to 4 GHz. A computer simulation is conducted to compare the experimental and numerical results. Additionally, we measured the SE of the PC case in a reverberation chamber (RC). The SE values of the PC case for the three axes in the case of FAC and RC are within 4 dB. The results show that this SE measurement technique, using electro-optic sensors and a VNA, is useful for both FAC and RC.