Optics/Photonics in Security and Defence最新文献

{"title":"Arbitrary waveform generation using optical direct digital synthesis","authors":"J. Chester-Parsons","doi":"10.1117/12.2032736","DOIUrl":"https://doi.org/10.1117/12.2032736","url":null,"abstract":"The objective of this paper is to describe the progress of a project designed to build on recent photonic capabilities in order to develop an ultra-wide band, true Arbitrary Waveform Generator (AWG) capable of providing radar quality signals in the 500MHz to 20GHz spectrum using photonic integration. Within this scope, it is planned to create a single channel radar environment simulator based on a photonic waveform generator, which will demonstrate the dynamic range, stability, and high signal fidelity required to simulate the modern complex radar environment. The paper will present recent measurements of critical parameters that are vital for the practical realisation of this system on a chip.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128024305","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":"Design of high sensitivity detector for underwater communication system","authors":"J. S. Cheong, J. Ong, J. S. Ng, A. Krysa, F. Bastiman, J. David","doi":"10.1117/12.2031953","DOIUrl":"https://doi.org/10.1117/12.2031953","url":null,"abstract":"Al0.52In0.48P is the largest bandgap material in III-V non-nitride semiconductors that is lattice matched to a readily available substrate (GaAs). Having a bandgap narrower than that of GaN enables it to detect wavelengths around 480 nm. Such wavelengths have the best transmittance underwater and may be used as a carrier in underwater communication systems. We present an Al0.52In0.48P homo-junction Separate-Absorption-Multiplication-Avalanche-Photodiode (SAMAPD) as a high sensitivity detector for such an application. By increasing the neutral and space-charge region thicknesses, the peak response wavelength can be tuned to longer wavelengths with a narrower full-width-half-maximum (FWHM). The quantum efficiency of the detector reduces with FWHM and this is compensated by having an avalanche gain. At room temperature, the SAM-APD has a dark current of <20 pA for a 210 μm radius device up to 99.9% of breakdown voltage. The structure gives a narrow spectral FWHM of 22 nm with centre wavelength of 482 nm. An external quantum efficiency of 33% and 6410% at 482 nm is obtained at bias voltage of -19 V and -92.6 V respectively.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131917683","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":"Advances in AlGaInN laser diode technology for defence applications","authors":"S. Najda, P. Perlin, T. Suski, L. Marona, M. Boćkowski, M. Leszczynski, P. Wisniewski, R. Czernecki, R. Kucharski, G. Targowski, S. Watson, A. Kelly","doi":"10.1117/12.2028717","DOIUrl":"https://doi.org/10.1117/12.2028717","url":null,"abstract":"The latest developments in AlGaInN laser diode technology are reviewed for defence applications such as underwater telecommunications, sensor systems etc. The AlGaInN material system allows for laser diodes to be fabricated over a very wide range of wavelengths from u.v., i.e, 380nm, to the visible, i.e., 530nm, by tuning the indium content of the laser GaInN quantum well. Ridge waveguide laser diode structures are fabricated to achieve single mode operation with optical powers of >100mW in the 400-420nm wavelength range with high reliability. Visible light communications at high frequency (up to 2.5 Gbit/s) using a directly modulated 422nm Gallium-nitride (GaN) blue laser diode is reported. High power operation of AlGaInN laser diodes is also reviewed. We demonstrate the operation of a single chip, high power AlGaInN laser diode ‘mini-array’ consisting of a 3 stripe common p-contact configuration at powers up to 2.5W cw in the 408-412 nm wavelength range. Packaging of nitride laser diodes is substantially different compared to GaAs laser technology and new processes and techniques are required to optimize the optical power from a nitride laser bar. Laser bars of up to 4mm with 16 emitters have shown optical powers up to 4W cw at ~410nm with a common contact configuration. An alternative package configuration for AlGaInN laser arrays allows for each individual laser to be individually addressable allowing complex free-space and/or fibre optic system integration within a very small form-factor.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"305 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131513713","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 camera technologies for real-time false-color imaging in the SWIR band","authors":"J. Dougherty, Todd Jennings, M. Snikkers","doi":"10.1117/12.2032737","DOIUrl":"https://doi.org/10.1117/12.2032737","url":null,"abstract":"Previously real-time false-colored multispectral imaging was not available in a true snapshot single compact imager. Recent technology improvements now allow for this technique to be used in practical applications. This paper will cover those advancements as well as a case study for its use in UAV’s where the technology is enabling new remote sensing methodologies.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125860141","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":"Automated generation of high-quality training data for appearance-based object models","authors":"S. Becker, Arno Voelker, H. Kieritz, W. Hübner, Michael Arens","doi":"10.1117/12.2028714","DOIUrl":"https://doi.org/10.1117/12.2028714","url":null,"abstract":"Methods for automated person detection and person tracking are essential core components in modern security and surveillance systems. Most state-of-the-art person detectors follow a statistical approach, where prototypical appearances of persons are learned from training samples with known class labels. Selecting appropriate learning samples has a significant impact on the quality of the generated person detectors. For example, training a classifier on a rigid body model using training samples with strong pose variations is in general not effective, irrespective of the classifiers capabilities. Generation of high-quality training data is, apart from performance issues, a very time consuming process, comprising a significant amount of manual work. Furthermore, due to inevitable limitations of freely available training data, corresponding classifiers are not always transferable to a given sensor and are only applicable in a well-defined narrow variety of scenes and camera setups. Semi-supervised learning methods are a commonly used alternative to supervised training, in general requiring only few labeled samples. However, as a drawback semi-supervised methods always include a generative component, which is known to be difficult to learn. Therefore, automated processes for generating training data sets for supervised methods are needed. Such approaches could either help to better adjust classifiers to respective hardware, or serve as a complement to existing data sets. Towards this end, this paper provides some insights into the quality requirements of automatically generated training data for supervised learning methods. Assuming a static camera, labels are generated based on motion detection by background subtraction with respect to weak constraints on the enclosing bounding box of the motion blobs. Since this labeling method consists of standard components, we illustrate the effectiveness by adapting a person detector to cameras of a sensor network. While varying the training data and keeping the detection framework identical, we derive statements about the sample quality.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117123311","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 method for discriminating the Moon interference based on CES software","authors":"Zhijun Tu, Zhiwu Mei, Jun Yuan, Loulou Deng","doi":"10.1117/12.2028970","DOIUrl":"https://doi.org/10.1117/12.2028970","url":null,"abstract":"When the moon and the sun light enter into the field of view of the conical scanning earth sensor (CES), the real attitude of the spacecraft will be affected because of wrong CES measurements．To solve this problem, a new method based on the CES software can discriminate the interference effect．A series of ground are designed to verify this method effectiveness, and results indicate that this method can not only give a indication of the moon, but also can eliminate effect of the moon and the sun light on the CES’s measurements．Finally, the on-orbit flight data is presented to confirm this method validity．","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"483 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114279986","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":"Deformation measurement for satellite antenna by close-range photogrammetry","authors":"Shanping Jiang, Linhua Yang, Jie Xu, Jiang Yu","doi":"10.1117/12.2027507","DOIUrl":"https://doi.org/10.1117/12.2027507","url":null,"abstract":"The photogrammetric system in vacuum cryogenic environment is designed to measure the sharp deformation of the satellite antenna due to the thermal deformation. The method of the measurement is based on the close-range photogrammetric techniques. This system includes CCD photography assembly, scale bars, support structures and the software. A test was performed by using this system, and the sharp deformation of a reflecting antenna was measured. In the test, a plenty of data was acquired, then the measurement method was proved feasible. According to analysis, we can acquire that the relatively measurement precision by this system can reach to 1:20000.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115357218","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":"Truly random number generation: an example","authors":"D. Frauchiger, R. Renner","doi":"10.1117/12.2032183","DOIUrl":"https://doi.org/10.1117/12.2032183","url":null,"abstract":"Randomness is crucial for a variety of applications, ranging from gambling to computer simulations, and from cryptography to statistics. However, many of the currently used methods for generating randomness do not meet the criteria that are necessary for these applications to work properly and safely. A common problem is that a sequence of numbers may look random but nevertheless not be truly random. In fact, the sequence may pass all standard statistical tests and yet be perfectly predictable. This renders it useless for many applications. For example, in cryptography, the predictability of a randomly\" chosen password is obviously undesirable. Here, we review a recently developed approach to generating true | and hence unpredictable | randomness.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125614316","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":"Quantum cascade lasers for defense and security","authors":"T. Day, M. Pushkarsky, David Caffey, K. Cecchetti, Ron Arp, A. Whitmore, M. Henson, E. Takeuchi","doi":"10.1117/12.2031536","DOIUrl":"https://doi.org/10.1117/12.2031536","url":null,"abstract":"Quantum cascade laser (QCL) systems are mature and at the vanguard of a new generation of products that support military applications such as Infrared Countermeasures (IRCM) and targeting. The demanding product requirements for aircraft platforms that include reduced size, weight, power consumption and cost (SWaP-C) extends to portable, battery powered handheld products. QCL technology operates throughout the mid-wave (MWIR) and long-wave (LWIR) infrared to provide new capabilities that leverage existing thermal imaging cameras. In addition to their suitability for aircraft platforms, QCL products are a natural fit to meet operator demands for small, lightweight pointer and beacon capabilities. Field-testing of high power, lightweight, battery operated devices has demonstrated their utility across a range of air and ground applications. This talk will present an overview of QCL technology and the Defense and Security products and capabilities that are enabled by it. This talk will also provide an overview of the extensive environmental and performance testing associated with products based on QCL technology.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123058740","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":"Polarity inversion attack prevention by physical properties of Y00 quantum stream cipher","authors":"T. Iwakoshi, O. Hirota","doi":"10.1117/12.2029029","DOIUrl":"https://doi.org/10.1117/12.2029029","url":null,"abstract":"This paper presents the physical prevention probability of an Intensity-Shift-Keying (ISK) Y00 quantum stream cipher against a polarity inversion attack, where the attacker in the middle of the communication line intercepts legitimate sender’s messages and resends false messages to the legitimate receiver by inverting some of signal polarities. Message falsification is recognized as a major issue in the field of mathematical encryption. Therefore, the attack should also be studied in the field of physical encryption. Y00 protocol was proposed by H. P. Yuen in 2000 to hide even ciphertexts from eavesdroppers under quantum noise of coherent light. Theoretical and experimental analyses of encryption strength of Y00 systems have also been studied against eavesdropping. However, there were not many studies about active attacks like message falsifications. Recent studies showed that the present ISK Y00 systems, whose communication bases are paired signals, may prevent the attack under the Known-Plaintext-Attack. To enhance the probability against the attack, a quadruple-signal-based ISK Y00 system was proposed, whose signal bases are sets of 4 signals. This study shows the proposed system has a prevention probability of 0.66665 per signal, while One-Time Pad used in BB84 cannot prevent message falsification under Known-Plaintext-Attack since polarity inversion directly falsifies the message.","PeriodicalId":344928,"journal":{"name":"Optics/Photonics in Security and Defence","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127946311","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}