Security and Defence Quarterly最新文献

{"title":"A comparison of synthetic thermal imagery created using MuSES and thermal imagery captured in the field","authors":"Jay Yu, Zohaib Khan, E. Guglielmo, Bin Lee","doi":"10.1117/12.2635147","DOIUrl":"https://doi.org/10.1117/12.2635147","url":null,"abstract":"The ability to model and simulate target signatures in a range of backgrounds under a range of environmental conditions are highly desirable as it allows for better understanding and assessment of the vulnerability of our soldiers in the battlefield. One main limitation of using game engine simulation is that they have limited capabilities and fidelity in simulating thermal signatures of targets and background. Physics based simulation software program on the other hand is more capable of simulating thermal properties of the scene and rendering a more physically realistic sensor image. In this study, we used MuSES (ThermoAnalytics), a physics based EO/IR signature simulation software to model and simulate the thermal properties and predicated thermal imagery of a real world scene with moving human targets. We used FLIR thermal IR cameras to capture the scene and the same scene was simulated in MuSES. A comparison of the synthetic and real thermal IR imagery was conducted and the progress made towards creating realistic thermal imagery in the land domain discussed","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"80 1","pages":"1227006 - 1227006-12"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77428312","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":"Modelling the behaviour of UAVs structural materials under continuous laser irradiations","authors":"V. Allheily, F. Retailleau, T. Jean, L. Merlat","doi":"10.1117/12.2637845","DOIUrl":"https://doi.org/10.1117/12.2637845","url":null,"abstract":"Whereas laser weapon systems are foreseen as a new possibility to counter unmanned aerial vehicles (UAVs), a better understanding of the complex phenomena occurring during the interaction of a high-energy laser beam with a flying structure is required to use those new innovative defense devices in an efficient but also a secure way. This paper first presents multiple material characterizations performed on glass fibers-reinforced plastics (GFRP), from which near-infrared spectroscopic data and high-temperature thermodynamic results are later implemented into multiphysics simulations. Numerical outcomes from the models are then compared to experimental recordings arising from laser trials carried out with varying power densities (75, 150 and 300 W/cm2) and with illumination times of several seconds. A very good agreement is shown between temperature data collected during laser experiments and temperature values from computations.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"19 1","pages":"1227306 - 1227306-10"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89459845","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":"Smart GPS spoofing to countermeasure autonomously approaching agile micro UAVs","authors":"I. Buske, A. Walther, Daniel Fitz, Juan S. Acosta, Andiy Konovaltsev, L. Kurz","doi":"10.1117/12.2636236","DOIUrl":"https://doi.org/10.1117/12.2636236","url":null,"abstract":"Small unmanned aerial vehicles (UAVs) are increasingly becoming a challenge for both civilian and military security. Even simple modifications of these inexpensive and widely available systems can create a serious threat which potentially causes major damage. Using signals from global navigation satellite system (GNSS), UAVs are able to operate over long distances and to find their target zone without remote control of a pilot. In this flight mode, radio direction finder cannot detect any transmitted signal. Typical countermeasures like RF jamming or Wi-Fi hacking become ineffective to stop the threat. The DLR smart GPS spoofing approach is a promising technology for a cost-effective countermeasure against such autonomously flying Micro UAVs. Several dedicated devices must reliably interact to fulfil this task. The optical identification and position measurement of the UAVs was developed at the DLR Institute of Technical Physics. By optimizing the tracking processes and the laser ranging systems, even small and agile targets can be tracked. The measured position and flight data are forwarded to a GPS spoofing system developed by the DLR Institute of Communications and Navigation. The emitted GPS signal is modified in such a way that the UAV leaves its original flight trajectory and is redirected to a save one. Outside the protected area the UAV can be forced to ground without collateral damages. The feedback loop via the independent optical position measurement ensures that the desired flight trajectory is maintained. The basic functionalities of the smart GPS spoofing countermeasure were successfully demonstrated in realistic field tests. The optical setup and first results will be discussed.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"35 1","pages":"1227309 - 1227309-6"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78363305","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":"Tailoring hyperspectral background models to target detection problems","authors":"A. Schaum","doi":"10.1117/12.2633989","DOIUrl":"https://doi.org/10.1117/12.2633989","url":null,"abstract":"Two unconventional probability distribution models for spectral backgrounds are described. Their utility is demonstrated for contrasting problems in detection: of atmospheric plumes and of sub-pixel opaque ground targets. Neither background model belongs to the conventional class of elliptically contoured distributions.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"8 1","pages":"1227202 - 1227202-7"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75329936","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":"Simulation of caustics caused by high-energy laser reflection from melting metallic targets adapted by a machine learning approach","authors":"A. Azarian, G. Franz, D. Wegner, Stefan Kessler, M. Henrichsen","doi":"10.1117/12.2636218","DOIUrl":"https://doi.org/10.1117/12.2636218","url":null,"abstract":"We present a model that calculates the reflected intensity of a high-energy laser irradiating a metallic target. It will enable us to build a laser safety model that can be used to determine nominal ocular hazard distances for high-energy laser engagements. The reflection was first measured in an experiment at 2 m distance from the target. After some irradiation time, the target begins to melt and the reflected intensity presents intensity patterns composed of caustics, which vary rapidly and are difficult to predict. A specific model is developed that produces similar caustic patterns at 2 m distance and can be used to calculate the reflected intensity at arbitrary distances. This model uses a power spectral density (PSD) to describe the melting metal surface. From this PSD, a phase screen is generated and applied onto the electric field of the laser beam, which is then propagated to a distance of 2 m. The simulated intensity distributions are compared to the measured intensity distributions. To quantify the similarity between simulation and experiment, different metrics are investigated. These metrics were chosen by evaluating their correlation with the input parameters of the model. An artificial neural network is then trained, validated and tested on simulated data using the aforementioned metrics to find the input parameters of the PSD that lead to the most similar caustics. Additionally, we tested another approach based on an autoencoder, which was tested on the MNIST dataset, to eventually generate a phase screen directly by using the caustics images.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"2012 1","pages":"1227305 - 1227305-14"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73698102","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":"High-energy laser experiments for vulnerability studies in the context of the European TALOS program","authors":"M. Taillandier, R. Peiffer, B. Colomer, R. Ortiz, E. Chalumeau, M. Pommies","doi":"10.1117/12.2635076","DOIUrl":"https://doi.org/10.1117/12.2635076","url":null,"abstract":"This article reports a contribution to laser vulnerability involving a series of experiments of High-Energy Laser (HEL) effects, at the Vulnerability Test Facility (VTF), in Talence, France. The activity is realized in the framework of the Tactical Advanced Laser Optical System (TALOS) European project led by CILAS, as part of the “Preparatory Action on Defense Research” (PADR), with the objective of creating European capabilities in Laser Directed Energy Weapon (LDEW) technologies. The trial facility implements a 1.07µm continuous wave multi-kW high-energy modular laser source and is highly capable in emulating representative laser engagements. The targets of interest include miscellaneous target envelop materials, UAV components and mini-drones. The trials generate plenty of data and observations useful for a target vulnerability assessment. This constitutes elements to progress in HEL vulnerability and is a first step in clearing the path for a technical roadmap of a future LDEW capability. This project has received funding from the European Union’s Preparatory Action on Defense Research under grant agreement No. 831726. The statements made herein represent the opinion and findings of the authors. The European Union and the European Defense Agency are not responsible for any use that may be made of the information they contain.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"310 1","pages":"122730B - 122730B-12"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79961676","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":"Influence of turbulence on active compressive sensing imaging","authors":"G. Paunescu, P. Lutzmann, D. Wegner","doi":"10.1117/12.2637774","DOIUrl":"https://doi.org/10.1117/12.2637774","url":null,"abstract":"This paper presents experimental investigations on active compressive sensing imaging through turbulence. We developed a laboratory testbed in which different compressive sensing configurations have been tested under various turbulence conditions. Series of images of a target were acquired and analyzed using three different metrics. The measurements have been performed under continuous-wave laser illumination at 635 nm.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"85 1","pages":"122720E - 122720E-7"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76724853","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":"Threat detection, identification, and optical counter measures for space-based applications","authors":"T. Haarlammert, A. Kwiatkowski, M. Möller, F. Kröber, U. Schmidt, S. Chelkowski","doi":"10.1117/12.2635953","DOIUrl":"https://doi.org/10.1117/12.2635953","url":null,"abstract":"The field of Space Situational Awareness (SSA) has seen increasing interest in recent years. As SSA is covering a wide range of applications, the activities are categorized in three main areas: space weather, near-earth objects and Space Surveillance and Tracking (SST). The latter one is covering active and inactive satellites and other man-made objects orbiting Earth. Consequently there are activities focusing on debris and inactive satellites on one hand, which can be seen as maintenance activities allowing humankind long-term access to space. On the other hand, SST covering active satellites is in principle a safety measure for space-based missions. Key words that arise in this context are detection, tracking and identification. These are the key ingredients for in-orbit threat detection. When these ingredients are mastered and dedicated solutions are developed, there is only a small step to go using the gained knowledge and same abilities to perform optical countermeasures. At Jena-Optronik GmbH, we already have a variety of sensors for specific applications in the field of SST available. Our product range covers visible cameras, LiDARs and specific laser detection sensors. Consequently, we recently started increasing our activity in SST to develop dedicated solutions tailored to the specific needs of this application field. Currently, a thermal infrared camera is in development and furthermore we plan to combine all necessary sensors for SST of active satellites in a dedicated SST sensor suite. This suite contains a control electronics unit, which combines all data from the connected sensors to form one dataset that covers the satellite surrounding volume and identifies incoming threats. In a next step active sensors can be used to follow incoming threats and hinder them from observing the satellite with the SST sensor suite and in particular its other payloads. This paper will provide an introduction into the topic. It will cover an overview of the concepts and needs for different sensors forming a SST sensor suite. Furthermore, the latest advances in our developments are presented and future steps and activities as well as sensors are motivated.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"4 1","pages":"1227307 - 1227307-16"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84793063","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":"Local estimation of parametric point spread functions in thermal images via convolutional neural networks","authors":"Florian Piras, Edouard De Moura Presa, P. Wellig, M. Liebling","doi":"10.1117/12.2636252","DOIUrl":"https://doi.org/10.1117/12.2636252","url":null,"abstract":"Thermal image formation can be modeled as the convolution of an ideal image with a point spread function (PSF) that characterizes the optical degradations. Although simple space-invariant models are sufficient to model diffraction-limited optical systems, they cannot capture local variations that arise because of nonuniform blur. Such degradations are common when the depth of field is limited or when the scene involves motion. Although space-variant deconvolution methods exist, they often require knowledge of the local PSF. In this paper, we adapt a local PSF estimation method (based on a learning approach and initially designed for visible light microscopy) to thermal images. The architecture of our model uses a ResNet-34 convolutional neural network (CNN) that we trained on a large thermal image dataset (CVC-14) that we split in training, tuning, and evaluation subsets. We annotated the sets by synthetically blurring sharp patches in the images with PSFs whose parameters covered a range of values, thereby producing pairs of sharp and blurred images, which could be used for supervised training and ground truth evaluation. We observe that our method is efficient at recovering PSFs when their width is larger than the size of a pixel. The estimation accuracy depends on the careful selection of training images that contain a wide range of spatial frequencies. In conclusion, while local PSF parameter estimation via a trained CNN can be efficient and versatile, it requires selecting a large and varied training dataset. Local deconvolution methods for thermal images could benefit from our proposed PSF estimation method.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"20 1","pages":"1227009 - 1227009-8"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82095902","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":"Compact multi-watt QCL module","authors":"F. Münzhuber, L. Späth, H. Tholl","doi":"10.1117/12.2636264","DOIUrl":"https://doi.org/10.1117/12.2636264","url":null,"abstract":"We report on the realization of a multi-emitter quantum cascade laser system with optimized package volume. A multidimensional bonding of chip-on-substrate units allows for close packaging of several chips. The emission of several chip-on-substrate units with an emission wavelength around 3.9 µm are geometrically combined to achieve a multi-Watt emission power level while obtaining a symmetric beam profile of the emission. A dedicated integrated electronic circuit provides individual pulse control, which enables individual timing for each emitter.","PeriodicalId":52940,"journal":{"name":"Security and Defence Quarterly","volume":"10 5 1","pages":"122730G - 122730G-12"},"PeriodicalIF":0.0,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73073529","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}