On the impact of arbitrary nozzle or dome configurations on dielectric endfire antenna performance in industrial radar level gauging

Dielectric antennas commonly used in radar based industrial level gauging often need to cross metallic nozzles or domes with arbitrary dimensions. In this article, the detrimental effects of such configurations are investigated. Two antennas incorporated into nozzles of different lengths and diameters are exemplarily evaluated to reveal the variations in antenna parameters such as the peak directivity as well as in the total measurement performance in a well established test scenario in industrial level measurement emulated by a radar system simulator. It is shown that it is beneficial to minimize the nozzle effects by careful antenna design, like e.g. by utilizing tightly guiding dielectric waveguides to cross the nozzle or by making use of optimized metallic launching horns in order to control the excitation of parasitic eigenmodes inside the nozzle.