Stephan Kruse successfully completed his doctorate on the topic of "Photonic Radar Circuits and Systems for Coherent mm-Wave Large Aperture Phased Array MIMO Systems" under the supervision of Prof. Dr.-Ing. Christoph Scheytt. Congratulations to him!
Abstract:
The angular resolution of a phased array antenna is inversely proportional to it’s aperture size. The high electrical losses limit the aperture size of modern all-electric radar systems to a few cm. This poses a significant problem for a variety of applications, especially for high resolution radar systems.
In this doctoral thesis, various novel photonic radar systems are presented and mathematically analyzed. Furthermore, the different systems are simulated in the optical design environment Lumerical Interconnect. Since all other photonic radar architectures presented are based on the FMCW MIMO radar system with optical LO distribution and optical return path, this system is also simulated in the electrical design environment ADS.
After a successful analysis, novel circuit topologies for the different photonic radar systems will be presented, including an novel optoelectronic mixer. Subsequently, the first transceiver chipset of a photonic radar system with optical LO distribution will be presented. A demonstrator based on this chipset, with an aperture size of 50 cm, achieves an angular resolution of 0.4°, which is close to the theoretically possible limit of 0.3°.
The appendix of this work also presents two 77 GHz frequency synthesizers with extremely low phase noise - one with an optical output, the other with an electrical output. In addition, the appendix contains further mathematical considerations.
