{"title":"Delamination Detection in Glass-Fibre Reinforced Polymer (GFRP) Using Microwave Time Domain Reflectometry","authors":"M. F. Akbar, G. Jawad, L. Danoon, R. Sloan","doi":"10.23919/EURAD.2018.8546540","DOIUrl":"https://doi.org/10.23919/EURAD.2018.8546540","url":null,"abstract":"Glass Fibre Reinforced Polymer (GFRP) is an important material that is used in different engineering applications, such as the rehabilitation of structures. However, delamination can occur between GFRP laminates and the metallic surfaces to which they are applied. The existence of such defects can cause major failures and compromise the integrity of the entire component. Hence, delamination detection is extremely important to maintain the integrity of any component that involves GFRP laminate. The unique layered nature of the GFRP material in terms of dielectric properties renders most Non-Destructive Testing/Evaluation (NDT/E) techniques inadequate to detect its delamination. However, microwave NDT/E can be regarded as an excellent choice for such purpose due to the ability of microwave signals to penetrate GFRP structures and detect the changes in their internal structures.This paper proposes a novel microwave NDT/E technique that uses Fourier analysis to analyze the reflections from a GFRP structure in the time domain. By scanning a back-drilled GFRP sample within the frequency range of 18 to 26.5 GHz, the proposed technique has proved to detect delamination thicknesses down to 1 mm. The technology reported in this paper represents a significant advance in the efforts to solve the currently challenging task of inspecting GFRP laminates for defects.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126467358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Christina Knill, B. Schweizer, Philipp Hügler, C. Waldschmidt
{"title":"Impact of an Automotive Chirp-Sequence Interferer on a Wideband OFDM Radar","authors":"Christina Knill, B. Schweizer, Philipp Hügler, C. Waldschmidt","doi":"10.18725/OPARU-10201","DOIUrl":"https://doi.org/10.18725/OPARU-10201","url":null,"abstract":"OFDM-based radar schemes are promising candidates to solve inherent limitations of frequency-modulated schemes. However, for a practical implementation in the automotive environment with an increasing amount of sensors and disturbances, not only the performance of the modulation scheme is important but also how it can perform in coexistence with other modulation schemes. In this paper, measurements are shown to investigate the impact of chirp-sequence-based sensors on a wideband OFDM radar. Furthermore, a straightforward method to mitigate and eliminate the interference on the receive signal is presented that allows reliable target detection even under severe chirp-sequence interference.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134152153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A New Super-Resolution Technique for Direction (and Time) of Arrival Detection","authors":"A. Omar","doi":"10.23919/eumc.2018.8541498","DOIUrl":"https://doi.org/10.23919/eumc.2018.8541498","url":null,"abstract":"A new technique for resolving different directions (or times) of arrival beyond the Rayleigh diffraction limit is presented. It is based on the Euclidean Algorithm for polynomial factorization and is implemented as a simple polynomial division (deconvolution) followed by a polynomial-root search. Similar to other super-resolution techniques, it reflects the exchangeability between bandwidth and signal-to-noise ratio governed by Shannon information-capacity concept. The core idea of the technique is borrowed from the error correction analysis of the Generalized Reed-Solomon codes used in channel coding. Both noiseless and noisy synthetic measurements of the output signals of a uniform linear antenna array are used for verifying the technique.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134624132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Martin Stolz, M. Wolf, F. Meinl, M. Kunert, W. Menzel
{"title":"A New Antenna Array and Signal Processing Concept for an Automotive 4D Radar","authors":"Martin Stolz, M. Wolf, F. Meinl, M. Kunert, W. Menzel","doi":"10.23919/EURAD.2018.8546603","DOIUrl":"https://doi.org/10.23919/EURAD.2018.8546603","url":null,"abstract":"On the way to Highly Automated Driving (HAD), new conditions for sensors used in vehicles arise. To achieve a highly accurate environmental perception the resolution of radar sensors has to be increased. Only with fine grained sensor information, it is possible to maneuver safely and highly automated at all road conditions in urban and rural surroundings. A prototypical implementation of such a sensor, which fulfills all these requirements, is presented in the following as automotive 4D radar. The relevant parts of the baseband signal processing are explained in combination with the used modulation waveform. A new antenna array arrangement is introduced which provides the ability to measure angles in both azimuth and elevation. To estimate the two angles of arrival a method which performs this in combination is exemplified. First measurements with a cyclist are recorded and show a radial speed enhanced 3D radar image. The first results are extremely promising. For validation of the measured data, also a simulation of the same scenario with identical system parameters is performed and shown.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131855121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peter J. Speirs, A. Schröder, M. Renker, P. Wellig, A. Murk
{"title":"Comparisons Between Simulated and Measured X-band Signatures of Quad-, Hexa- and Octocopters","authors":"Peter J. Speirs, A. Schröder, M. Renker, P. Wellig, A. Murk","doi":"10.23919/EURAD.2018.8546612","DOIUrl":"https://doi.org/10.23919/EURAD.2018.8546612","url":null,"abstract":"This paper presents and compares finite element method (FEM) and method of moments (MoM) monostatic radar cross-section (RCS) simulation results for an example quadcopter, hexacopter and octocopter at X-band, as well as comparing the simulations against measurements for quad- and hexacopters. In particular we explore the extent to which simplified CAD models can be used to estimate the scattering from multi-rotor unmanned aerial vehicles (UAVs). We also consider the importance of model complexity for micro-Doppler rotor simulations.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"219 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116127892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Non-linear effect mitigation for FMCW radar system","authors":"N. Bouhlel, S. Méric, C. Moullec, C. Brousseau","doi":"10.23919/EURAD.2018.8546550","DOIUrl":"https://doi.org/10.23919/EURAD.2018.8546550","url":null,"abstract":"In this paper, we deal with a frequency modulated continuous wave (FMCW) radar used for localizing and tracking targets by frequency evaluation of the received radar beat signal. The radar system achieved with a primary radar (reader) and a secondary radar (transponder) is addressed as super high frequency (SHF) radio frequency identification (RFID). Consequently, considering the transponder as an active target, we achieve an identification application thanks to the shift frequency induced by the transponder. Moreover, the impact of the non-linearity behavior of this transponder on the localization performance, is investigated and a solution is proposed for cancelling non-linear effects.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"361 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115432859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Barquinero, Julián Gómez, A. Mediavilla, J. Besada, B. Galocha
{"title":"A Compact Simultaneous K/S-Band Monopulse Tracking Feed for Future Earth Observation Applications","authors":"C. Barquinero, Julián Gómez, A. Mediavilla, J. Besada, B. Galocha","doi":"10.23919/eurad.2018.8546580","DOIUrl":"https://doi.org/10.23919/eurad.2018.8546580","url":null,"abstract":"This paper presents a novel K/S band monopulse tracking feed for the next generation of Earth Observation (EO) applications in the 25.5 to 27 GHz band. A brief review of the feed, which covers the design and development of a dual band coaxial horn, a TE21 resonant tracking coupler, OMTs and polarizers (septum and corrugated), is included. Characterization of the complete feed in both bands is also summarized in the paper, as well as the evaluation of several dielectric materials for the radome feed window, which is particularly critical in K-band","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114562803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Grzyb, P. R. Vazquez, N. Sarmah, B. Heinemann, U. Pfeiffer
{"title":"Performance Evaluation of a 220–260 GHz LO Tunable BPSK/QPSK Wireless Link in SiGe HBT Technology","authors":"J. Grzyb, P. R. Vazquez, N. Sarmah, B. Heinemann, U. Pfeiffer","doi":"10.23919/eumc.2018.8541785","DOIUrl":"https://doi.org/10.23919/eumc.2018.8541785","url":null,"abstract":"This paper reports on characterization and performance evaluation of a 1-m 220–260 GHz tunable carrier wireless link with highly-integrated direct-conversion quadrature TX/RX modules implemented in 0.13µm SiGe HBT technology with ft/fmax of 350/550 GHz. Under limited IF bandwidth constraints of 15 GHz, the maximum achieved data rates for BPSK/QPSK modulation schemes are 35 Gbps with an EVM of 28.9 % and 65 Gbps with an EVM of 31.5 %, respectively. It is further found that the current link performance is not limited by the AWGN-related SNR but mainly affected by the RF front-end imperfections related to large operation bandwidth.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114231471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Human Detection by Deep Neural Networks Recognizing Micro-Doppler Signals of Radar","authors":"Jihoon Kwon, Seungeui Lee, Nojun Kwak","doi":"10.23919/EURAD.2018.8546605","DOIUrl":"https://doi.org/10.23919/EURAD.2018.8546605","url":null,"abstract":"The purpose of this paper is to show the effectiveness of Deep neural networks (DNN) for recognizing the micro-Doppler radar signals generated by human walking and background noises. To show this, we collected various micro-Doppler signals considering the actual human walking motion and background noise characteristics. Unlike the previous researches that required a complex feature extraction process, we directly use the FFT result of the input signal as a feature vector without any additional pre-processing. This technique helps not to use heuristic approaches to get a meaningful feature vector. We designed two types of DNN classifier. The first is the binary classifier to classify human walking Doppler signals and background noises. The second is the multiclass classifier that is roughly able to recognize a circumstance of a place as well as human walking Doppler signals. DNN for the binary classifier showed about 97.5% classification accuracy for the test dataset and DNN(ReLU) for the multiclass classifier showed about 95.6% accuracy.","PeriodicalId":171460,"journal":{"name":"2018 15th European Radar Conference (EuRAD)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126677976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}