Abstract

The development and simulation of a rectangular wave guide with FEM for transmission/reflection (T/R) coefficient analysis has been described. T/R coefficient calculated using Finite Element Method (FEM), Vector network analyzer (VNA) and Nicholson Ross Weir (NRW) techniques were compared. In this work, a 30 mm PTFE and 50 mm PTFE samples were used as materials under test (MUT). The result obtained from calculation and measurement of the two samples showed that the result from the FEM calculation was closer to the measured value than NRW. A mean relative error analysis was carried out which confirmed that the relative error associated to FEM with respect to the 30 mm thick PTFE sample was 0.062 and 0.078 for S21 and S11 respectively whereas the NRW had a relative error of 0. 086 and 0.114 for S21 and S11 for the same PTFE sample respectively.

Key words: Finite element method, vector network analyser, PTFE, T/R coefficient