Attenuation estimation of long coaxial cable with regularization method

The attenuation of the coaxial cable plays a key role in signal analysis, especially in precise measurement field. In general, the attenuation is measured by VNA. However, it needs to bend the cable to reduce the distance between the two ports when the length is long. This way easily breaks the actual work state, and the results may be quite different from the real. Other approaches, such as theoretical model calculation method, sweep frequency test method have obvious defects such as low precision and low efficiency. In this investigation, an inverse analysis approach of regularization method is developed. Preliminary verification has been carried out with simulation and experimental work; results show that the regularization method applied has good performance in estimating the attenuation of the coaxial cable. Moreover, as the biggest influence factor, the noise is also discussed in this work.