Modeling Relative Humidity and Temperature Effects on Scattering Parameters in Transmission Lines

This paper is focused on the development of a simulation method to evaluate relative humidity (RH) and temperature effects of scattering parameters on transmission systems from DC to 26 GHz. The first step in the analysis is to design a number of experiments to quantify the environmental impacts on S-parameters. Then, a method is proposed to model the RH and temperature effects on microstrip transmission lines, without the need for extensive and complex S-parameter data collection or the use of an environmental chamber. The proposed method was achieved after data analysis which included filtering, fitting, and interpolation, both in magnitude and phase of the S-parameters. The results show that the RH and temperature effects on transmission systems can be accurately modeled and predicted. This method can be applied to different printed circuit board materials, and it will be useful to engineers and manufacturers interested in predicting environmental impacts on system performance.