LTCC Endfire Antenna With Housing for 77-GHz Short-Distance Radar Sensors

An integrated antenna concept for miniaturized industrial short-distance continuous-wave (CW) radar-systems is presented. Highly accurate measurements with objects in the antenna's near field place special demands on the antenna design. By simulations, the letter shows a reduced phase error at short-distance measurements caused by the usage of corrugations and a novel housing concept. In addition to the increased accuracy the housing protects the sensor from cooling liquids and flying debris. This protection is further reinforced by a polymeric covering that does not influence the measurement accuracy, but allows the on-the-fly observation of metal cutting processes. Different covering polymers are determined relating to the antenna properties and resistance against chemicals. The influences on the beam shape and return loss are shown and verified by measurements.