We offer a position as an
Early Stage Researcher (M/F/D)
in the Marie Skłodowska-Curie Innovative Training Network Project MENELAOSNT in the field
Adaptive compressed sensing methods for more efficient radar detection and localization (ESR6)
The range resolution of a radar system is directly propotional to its bandwidth. Applications demand more and more range resolution and thus higher high frequency bandwidths. Unfortunately, these bandwidths are limited because of several reasons like techical (hardware limitations), atmospherical windows and specific regulations. A promising approach to overcome these limitations is to use conventional small band radars with disjoint frequency bands and fuse the data using compressed sensing methods to gain a high overall bandwidth.
The main focus of the project lies on the scientific investigation of innovative radar signal processing methods on real measured data like compressed sensing to overcome millimeter wave radar system limitation in bandwidth, which is caused in the usage of only relative small particular frequency bands.
Thereto two suitable measurement setups will be developed to investigate the performance of the available hardware and the implementation of compressed sensing algorithms applied to the measured data. The first setup will be based on a network analyzer for measurements in an anechoic chamber and the second one on a coherent multi frequency radar system for open space measurements working at particular radio frequencies in the frequency band up to 96 GHz. Thereby it will be possible to investigate the potential of achieving super resolution below 3 mm in the range direction and of improving inverse synthetic aperture radar (ISAR) image resolution.
The successful candidate will be employed for a maximum period of three years full-time equivalent and receives a generous financial package plus an additional mobility and family allowance according to the rules for Early Stage Researchers (ESRs) in an EU Marie Sklodowska-Curie Actions Innovative Training Networks (ITN). A career development plan will be prepared for each fellow in accordance with his/her supervisor and will include training, planned secondments and outreach activities in partner institutions of the network. The ESR fellows are supposed to complete their PhD thesis by the end of the 3rd year of their employment. For more information please visit the Marie Sklodowska-Curie Actions Innovative Training Networks website.
YOUR TASKS
- Theory development and simulations on the application of compressed sensing methods to reconstruct high resolution range profiles from two disjoint band radar signals
- Generation of data using a laboratory setup as well as a set of radars and processing the data with the developed processor.
- Investigation of adaptive sensing and dictionary learning methods to acquire radar data.
- Application to various radar domains, including SAR or ISAR imaging
PROFILE
- Master of Science in Electrical Engineering, Physics or Mathematics
- ESRs must demonstrate that their ability to understand and express themselves in both written and spoken English is sufficiently high for them to derive the full benefit from the network training. English level C1
- Experience in compressed sensing
- Experience in imaging and SAR processing
- Knowledge in Matlab
PLANNED SECONDMENTS
The algorithmic and the experimental part will be centred at Fraunhofer FHR. For the adaption of the process to measured ISAR data Sabanci University can provide support.
- SU (SPIS), Sabanci, Turkey, Prof. Dr. M. Çetin, 3 months, CS algorithm development.
- WIS (SAMPL), Israel, Prof. Dr. Y. Eldar, 2 months, refinement of CS algorithms.
- USI (ZESS), Siegen, Germany, Prof. O. Loffeld, 4 months, application of algorithms to different sensor types.
ADDITIONAL INFORMATION
The Fraunhofer Institute for High Frequency Sensors and Radar Techniques FHR develops concepts, algorithms and systems in the electromagnetically sensing domain, mostly in the field of radar. In the last years compressed sensing becomes more and more important for radar signal processing, because physical and regulatory limits slow down the developments of new innovative system improvements.
An appropriate example, where compressed sensing can be used to improve the radar system characteristics, is the maximization of the range resolution of a radar system. Up to now , the radar system with the highest bandwidth worldwide was developed by the Fraunhofer institute FHR and works with a very high center radio frequency (RF) of 290 GHz and a bandwidth of 44 GHz. It can be shown, that ISAR images and SAR images with an image resolution of 3.5 mm can be processed.
Radar systems operate mostly in lower frequency bands up to 100 GHz and provide much lower instantaneous bandwidths. This is caused in performance limitations of available system components, frequency band restrictions to avoid high atmospheric attenuation and regulations of the frequency band usage.
Using compressed sensing these conventional small radar bands should be combined to a high resolution radar. In a further step also ISAR imaging should be investigated.
Literature:
- J. Ender, “On Compressive Sensing applied to Radar,” Signal Processing, vol. 90, pp. 1402-1414, 2010.
- S.Stanko, M.Caris, A.Wahlen, R.Sommer, J.Wilcke, A.Leuther, A.Tessmann, “Millimeter resolution with radar at lower terahertz,” 14th International Radar Symposium (IRS), vol.1, pp. 235-238, 2013.
- H. Essen, “High Resolution Tower-Turntable ISAR with the Millimetre Wave Radar COBRA (35 / 94 / 220 GHz),” 7th European Conference on <http://ieeexplore.ieee.org/xpl/mostRecentIssue.jsp?punumber=5757081>Synthetic Aperture Radar (EUSAR), 2008.
Fraunhofer FHR is one of the leading and largest research institutes in Europe in the area of high frequency and radar techniques. For its partners, the institute develops customized concepts, techniques and systems for electromagnetic sensors from the microwave range through to the lower terahertz range. At Fraunhofer FHR, research activities focus on high frequency sensors for high-precision range or position determination as well as imaging systems with resolutions of up to 3.75 mm. The application spectrum of these devices ranges from reconnaissance, surveillance and protection systems to real-time capable sensors for traffic and navigation as well as quality assurance and non-destructive testing. The systems from Fraunhofer FHR are renowned for their reliability and robustness: radar and millimeter wave sensors are ideal for complex tasks, also under critical ambient conditions. They operate under high temperatures, in the presence of vibrations or in zero visibility conditions caused by dense smoke, steam or fog. The techniques and systems developed at Fraunhofer FHR are used, on the one hand, to conduct research on new technologies and designs. On the other hand, the institute – in cooperation with companies, authorities and other public bodies – develops prototypes that are designed to master currently unsolved challenges. The technologies used range from traditional waveguide techniques to highly-integrated silicon-germanium chips with frequencies of up to 300 GHz. The ability to carry out non-contact measurements and penetrate materials opens up numerous possibilities for the localization of objects and persons. Due to their special capabilities resulting from the progress in miniaturization and digitalization, the high frequency sensors from Fraunhofer FHR are an affordable and attractive option for a growing number of application areas.
The position will be located at
Fraunhofer-Institut für Hochfrequenzphysik und Radartechnik FHR
Fraunhofer-Straße 20
55334 Wachtberg, Germany
Supervisor: Prof. Dr. Dirk Heberling, Prof. Dr. Peter Knott
Planned Recruitment date: 1st September 2020.
Eligibility Criteria and Mobility Rule
ESRs must, at the date of recruitment, be in the first four years (full-time equivalent research experience) of their research careers and have not been awarded a doctoral degree. Full-Time Equivalent Research Experience is measured from the date when the researcher obtained the first degree entitling him/her to embark on a doctorate (either in the country in which the degree was obtained or in the country in which the researcher is recruited), even if a doctorate was never started or envisaged. Researchers can be of any nationality.
ESRs must not have resided or carried out their main activity (work, studies, etc.) in the country of the recruiting beneficiary for more than 12 months in the 3 years immediately before the planned recruitment date. Compulsory national service, short stays such as holidays, and time spent as part of a procedure for obtaining refugee status under the Geneva Convention are not taken into account.