Comparison of nonuniform transmission lines with Gaussian and exponential impedance profiles for z-pinch

The circuit simulation of nonuniform transmission lines that were under consideration for the next generation of pettawatt-class z-pinch drivers was performed. It was confirmed that the power-transport efficiency of the designed radial transformer with an exponential impedance profile is higher than that with Gaussian profiles. Based on the Fourier´s theorem and the principle of superposition, it was found that there are considerable low-frequency components for an input voltage of half-sine wave with an angular frequency of 14MRad/s. Compared to the exponential transformer, the Gaussian transformers amplify the low-frequency components to a lower extent, which makes the difference in power efficiency between the two types of the transformers. The radial transformer also serve as a passive high-pass filter and the Gaussian transformer may give better performance than that the exponential transformer does if the signal transport rather than the power transport is concerned.