Level probing in highly overmoded waveguides

摘要

This paper deals with a tank level probing scenario using electromagnetic waves where the vessel supports a significant number of higher order modes which deteriorate the accuracy of the measurement. A signal model is presented which allows to estimate the accuracy of interferometric measurements taking higher order modes into account. Based on the predicted estimation an appropriate waveguide taper with a high suppression of parasitic modes is designed, fabricated and measured. The presented design approach is validated by measurements.