Influence of sample insertion hole on resonant cavity perturbation measuring method

Influence of sample insertion holes in resonant cavity for a measuring fixture was investigated experimentally and numerically. Shift of the resonant frequency caused by loaded sample decreased when the cavity height decreased or dielectric constant of a sample increased. Employing tall cavity improved measurement error. Using commercial simulators, it was found that disturbance of electric field near the sample insertion hole caused deviation of resonant frequency from the ideally closed cavity. The simulation result was inspected from the viewpoint of physical rationality.