Zero-bias model and compensation of VNA intermediate frequency system

A new zero-bias model and compensation procedure for the intermediate frequency (IF) signal processing system of the vector network analyzer (VNA) based on neural network is proposed in this paper. This procedure can be used to four IF channels with different conditions. The structure of the zero-bias compensation procedure in one port is given first. Then for four different channels, the same method is applied. The zero-bias is modeled by radial basis function neural network and the IF signal is compensated via the analysis based on the model. Finally, the proposed method is tested via AV3672 series VNA and the experiment shows that the method can well eliminate the zero-bias of the IF signal, and it is effective for zero-bias model and compensation.