Measurement method of electromagnetic shielding performance using time-frequency analysis and optical fiber link broadband antenna

We propose a evaluation method for electromagnetic shielding performance using an optical fiber link system with broadband antennas that consists of a transmitting optical fiber link system, receiving optical fiber link system, two broadband bi-corn antennas and a vector network analyzer. Our proposed method is based on a time domain analysis and a time-frequency analysis using short time Fourier transform. The proposed method eliminates the undesired waves from measured wave by using a time-domain technology and time-frequency analysis. It is proved that our proposed method can be used to evaluate the shielding effect for thin film type shielding sheet in the frequency range from 300 MHz to 6 GHz.