Industrial automation requires high accuracy distance measurement sensors in a multitude of different applications. Therefore the IHE develops special signal processing algorithms which achieve a very high distance measurement accuracy. Together with radar sensors developed in various other projects very competitive results have been achieved.
To achieve the highest distance measurement accuracy the classical FMCW signal processing has been combined with an additional phase evaluation. The novel algorithm allows to nearly reach the Cramer Rao lower bound and can be implemented in real time.
In hydraulic cylinder applications the correct detection of the piston position is indispensable. The developed K-band (24 GHz) FMCW radar system detects the piston position in a hydraulic cylinder based on the guided propagation of a radar signal. At a measurement repetition rate of 2 kHz, an accuracy of well below 200 µm was achieved for a hydraulic cylinder of 1 m in length.
Within the SUCCESS project a fully integrated radar transceiver at 122 GHz was realized. Based on the SUCCESS chip a complete low-cost radar module has been built. The package of the QFN radar front-end has a size of 8 mm × 8 mm and the whole radar module including the two stacked PCBs has a size of 66 mm × 55 mm × 21 mm. Accuracies of 200 μm and 2 μm are achieved over a distance of 1.9 m and 5 mm, respectively.
Based on a high performance radar developed at the Ruhr-Universität Bochum (RUB) and Fraunhofer FHR in Wachtberg a world record distance measurement accuracy of better than 1 µm has been achieved: