Comparison of free-space VNA and TDS measurements using transmission-type frequency selective surfaces

A method for directly comparing vector network analyzer (VNA) and time-domain spectrometer (TDS) measurements in free space using transmission-type frequency selective surfaces (FSSs) is proposed. The transmission characteristics of FSSs with artificially controlled frequency dispersions facilitate flexible and detailed comparisons of VNA and TDS measurements. Four FSSs were designed as verification devices of free space measurements. The proposed approach was demonstrated in the D and J bands by comparing the measurement results of the transmission amplitude and phase characteristics of the FSSs obtained using VNA and TDS systems. The amplitude and phase results obtained using both systems were in good agreement, confirming the consistency and validity of the VNA and TDS measurements.