Inline Millimeter Wave Radar Phase Measurements utilizing High Order Waveguide Modes

In this paper, we present a new concept for extremely sensitive frequency modulated continuous wave radar measurements within waveguides. Basis for this concept is the millimeter wave radar's outstandingly broad bandwidth that ensures precise detection of targets and its particularly sensitive phase. Moreover, the conversion of the fundamental TE₁₁ to the higher TE₀₁ mode with a broadband mode converter allows for advanced inline measurement setups. Therefore, simulations concerning the mode behavior are discussed and measurements that confirm the presented theory are demonstrated.