Self-mixing millimetre-wave radar on the basis of multiple surface reflections (MIRADOR)

• Applicant: Professor Dr.-Ing. Ingmar Kallfass
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: from 2020 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 433508405

In the frame of the DFG projects "active phase shifters for electronic beamsteering in the high millimetre-wave frequency range" (MilliPhase) and "highly integrated 3d radar systems at 240 GHz" (MilliScan) the group around Prof. Kallfass introduced and patented a new radar technique. The technique is based on the mixing of two or multiple reflected signals employing the self-mixing effect of a nonlinear component. The new method distinguishes itself from conventional radar methods (mono-static, bi-static, passive) in the sense that the receiver is spatially and electrically independent of the transmitter. In contrast to conventional radar techniques no common time or frequency basis exists between the transmitter and the receiver. The technique offers multiple application scenarios in the areas of production technologies, medicine, material analysis and safety and security. The project aims at evaluating the new radar technique through custom-designed radar sensors operating in two frequency ranges, and to make it exploitable for the application partner Balluff GmbH. The frequency ranges are chosen to lie in the ISM bands: In the 60 GHz band commerical off-the-shelf components are available in order to develop a low-cost radar prototype. In view of basic research aspects and in line with the product raodmap of Balluff the high millimetre-wave range above 100 GHz is of particular interest for high resolution and highly compact radar systems. Therefore, a second prototype for the new radar method shall operate in the frequency range around 240 GHz. Here, a strong link can be made to the prior art of our group in the projects MilliScan and MilliPhase. With the company Balluff GmbH a strong application partner could be found, for whose business area of short-range radar sensors the new method is particularly attractive. The basic research aspect and scientific findings of the project are given, on the one hand, through the investigation of the new radar technique, which can potentially address a wide range of applications, and on the other hand through the use of radar frequencies in the THz range at 240 GHz, which lie above today's state of the art by a factor of three in comparison to automotive radar and by a factor of four in comparison to short range radar at 60 GHz.

• DFG Programme: Research Grants (Transfer Project)
• Application Partner: Balluff GmbH