Technique for Eliminating Resonant Artifacts in Low Loss Material Measurement

This paper presents an iterative method by means of a Particle Swarm Optimization (PSO) algorithm to extract the permittivity and permeability of magnetic and non-magnetic materials accurately and stably at microwave frequencies. PSO algorithm is used to eliminate the resonant artifacts that arise in traditional and modified NRW techniques. This ill-behaved nature or resonant artifacts arise from transmission/reflection (T/R) measurements with low loss materials. In addition, due to tensor aspects related to magnetic materials, there is a continuous shift in resonant artifacts, and it is challenging to extract accurate scalar permittivity in partially magnetized state. In this work, it is shown that such resonant artifacts can be removed for the first time using a PSO algorithm and the corresponding simulated and measured results are provided for validation.