SPIE Defense + Commercial Sensing最新文献

{"title":"A worldwide physics-based high spectral resolution atmospheric characterization and propagation package for UV to RF wavelengths","authors":"M. Krizo, S. Cusumano, R. Bartell, Steven T. Fiorino, W. Bailey, Rebecca L. Beauchamp, M. Marciniak, K. P. Moore","doi":"10.1117/12.777572","DOIUrl":"https://doi.org/10.1117/12.777572","url":null,"abstract":"The Air Force Institute of Technology's Center for Directed Energy (AFIT/CDE) developed the High Energy Laser End-to-End Operational Simulation (HELEEOS) model in part to quantify the performance variance in laser propagation created by the natural environment during dynamic engagements. As such, HELEEOS includes a fast-calculating, first principles, worldwide surface-to-100 km, atmospheric propagation and characterization package. This package enables the creation of profiles of temperature, pressure, water vapor content, optical turbulence, atmospheric particulates and hydrometeors as they relate to line-by-line layer transmission, path and background radiance at wavelengths from the ultraviolet to radio frequencies. Physics-based cloud and precipitation characterizations are coupled with a probability of cloud free line-of-sight algorithm for all possible look angles. HELEEOS was developed under the sponsorship of the High Energy Laser Joint Technology Office. In the current paper an example of a unique high fidelity simulation of a bi-static, time-varying five band multispectral remote observation of laser energy delivered on a test object is presented. The multispectral example emphasizes atmospheric effects using HELEEOS, the interaction of the laser on target and the observed reflectance and subsequent hot spot generated. A model of a sensor suite located on the surface is included to collect the diffuse reflected in-band laser radiation and the emitted radiance of the hot spot in four separate and spatially offset MWIR and LWIR bands. Particular care is taken in modeling the bidirectional reflectivity distribution function (BRDF) of the laser/target interaction to account for both the coupling of energy into the target body and the changes in reflectance as a function of temperature. The architecture supports any platform-target-observer geometry, geographic location, season, and time of day; and it provides for correct contributions of the sky-earth background. The simulation accurately models the thermal response, kinetics, turbulence, base disturbance, diffraction, and signal-to-noise ratios.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125486269","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":"Wind-based navigation of a hot-air balloon on Titan: a feasibility study","authors":"R. Furfaro, J. Lunine, A. Elfes, K. Reh","doi":"10.1117/12.777654","DOIUrl":"https://doi.org/10.1117/12.777654","url":null,"abstract":"Current analysis of data streamed back to Earth by the Cassini spacecraft features Titan as one of the most exciting places in the solar system. NASA centers and universities around the US, as well as the European Space Agency, are studying the possibility of sending, as part of the next mission to this giant moon of Saturn, a hot-air balloon (Montgolfier-type) for further and more in-depth exploration. The basic idea would be to design a reliable, semi-autonomous, and yet cheap Montgolfier capable of using continuous flow of waste heat from a power source to lift the balloon and sustain its altitude in the Titan environment. In this paper we study the problem of locally navigating a hot-air balloon in the nitrogen-based Titan atmosphere. The basic idea is to define a strategy (i.e. design of a suitable guidance system) that allows autonomous and semi-autonomous navigation of the balloon using the available (and partial) knowledge of the wind structure blowing on the saturnian satellite surface. Starting from first principles we determined the appropriate thermal and dynamical models describing (a) the vertical dynamics of the balloon and (b) the dynamics of the balloon moving on a vertical plane (2-D motion). Next, various non-linear fuzzy-based control strategies have been evaluated, analyzed and implemented in MATLAB to numerically simulate the capability of the system to simultaneously maintain altitude, as well as a scientifically desirable trajectory. We also looked at the ability of the balloon to perform station keeping. The results of the simulation are encouraging and show the effectiveness of such a system to cheaply and effectively perform semi-autonomous exploration of Titan.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126197811","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":"Two-channel IR vibration sensor based on dynamic gratings in semiconductors and pyro-electrics","authors":"N. Kukhtarev, T. Kukhtareva, J. Caulfield, J. Wang, T. Murray, Y. Gnatenko, I. O. Faryna, P. Bukivskij, R. Gamernyk, A. Grabar","doi":"10.1117/12.778213","DOIUrl":"https://doi.org/10.1117/12.778213","url":null,"abstract":"Double-functional (optical and electrical) interferometer was realized using holographic recording of dynamic gratings in the semiconductor crystals of CdTe: V, CdTe:Ti and ferroelectric-pyroelectric crystal Sn2P2S6 (SPS). Also we introduce novel holographic single-beam wave-front division interferometer that is compact, do not need stabilization and are well suited for real-world applications.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121418060","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":"IR technology for enhanced force protection by AIM","authors":"R. Breiter, T. Ihle, W. Rode, J. Wendler, I. Rühlich, M. Haiml, J. Ziegler","doi":"10.1117/12.776747","DOIUrl":"https://doi.org/10.1117/12.776747","url":null,"abstract":"In all recent missions our forces are faced with various types of asymmetric threads like snipers, IEDs, RPGs or MANPADS. 2nd and 3rd Gen IR technology is a backbone of modern force protection by providing situational awareness and accurate target engagement at day/night. 3rd Gen sensors are developed for thread warning capabilities by use of spectral or spatial information. The progress on a dual-color IR module is discussed in a separate paper [1]. A 1024x256 SWIR array with flexure bearing compressor and pulse tube cold finger provides > 50,000h lifetime for space or airborne hyperspectral imaging in pushbroom geometry with 256 spectral channels for improved change detection and remote sensing of IEDs or chemical agents. Similar concepts are pursued in the LWIR with either spectroscopic imaging or a system of LWIR FPA combined with a cooled tunable Laser to do spectroscopy with stimulated absorption of specific wavelengths. AIM introduced the RangIR sight to match the requirements of sniper teams, AGLs and weapon stations, extending the outstanding optronic performance of the fielded HuntIR with position data of a target by a laser range finder (LRF), a 3 axis digital magnetic compass (DMC) and a ballistic computer for accurate engagement of remote targets. A version with flexure bearing cooler with >30,000h life time is being developed for continuous operation in e.g. gunfire detection systems. This paper gives an overview of AIM's technologies for enhanced force protection.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133626258","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":"Tuning of the detection wavelength in quantum dots-in-a-well infrared photodetectors","authors":"L. Höglund, P. Holtz, C. Asplund, Qin Wang, S. Almqvist, Erik Petrini, H. Malm, H. Pettersson, J. Andersson","doi":"10.1117/12.781227","DOIUrl":"https://doi.org/10.1117/12.781227","url":null,"abstract":"In this study, bias mediated tuning of the detection wavelength within the infrared wavelength region is demonstrated for quantum dots-in-a-well (DWELL) infrared photodetectors. In DWELL structures, intersubband transitions in the conduction band occur from a discrete state in the quantum dot to a subband in the quantum well. Compared to \"conventional\" quantum dot infrared photodetectors, where the transitions take place between different discrete bands in the quantum dots, new possibilities to tune the detection wavelength window are opened up, partly by varying the quantum dot energy levels and partly by adjusting the width and composition of the quantum well. In the DWELL structure used, an asymmetric positioning of the InAs quantum dot layer in a 8 nm wide In0.15Ga0.85As/GaAs QW has been applied which enables tuning of the peak detection wavelength within the long wavelength infrared (LWIR; 8 - 14 µm) region. When the applied bias was reversed, a wavelength shift from 8.5 to 9.5 µm was observed for the peak position in the spectral response. For another DWELL structure, with a well width of 2 nm, the tuning range of the detector could be shifted from the medium wavelength infrared (MWIR; 3-5 µm) region to the LWIR region. With small changes in the applied bias, the peak detection wavelength could be shifted from 5.1 to 8 µm. These tuning properties of DWELL structures could be essential for applications such as modulators and two-colour infrared detection.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"PP 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126535116","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":"Low-cost ladar imagers","authors":"S. Vasile, J. Lipson","doi":"10.1117/12.781586","DOIUrl":"https://doi.org/10.1117/12.781586","url":null,"abstract":"We have developed low-cost LADAR imagers using photon-counting Geiger avalanche photodiode (GPD) arrays, signal amplification and conditioning interface with integrated active quenching circuits (AQCs) and readout integrated circuit (ROIC) arrays for time to digital conversion (TDC) implemented in FPGA. Our goal is to develop a compact, low-cost LADAR receiver that could be operated with room temperature Si-GPD arrays and cooled InGaAs GPD arrays. We report on architecture selection criteria, integration issues of the GPD, AQC and TDC, gating and programmable features for flexible and low-cost re-configuration, as well as on timing resolution, precision and accuracy of our latest LADAR designs.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"6950 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129781336","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":"Modeling the detection of optical sights using retro-reflection","authors":"A. Mieremet, R. Schleijpen, P. N. Pouchelle","doi":"10.1117/12.774634","DOIUrl":"https://doi.org/10.1117/12.774634","url":null,"abstract":"Retro-reflection can be used for the detection and classification of optical systems. The probability of detecting sights over large ranges depends on parameters of the laser, the sight, the detector and the atmosphere. We have developed a software tool that simulates a sight detection system. With the use of this tool we can 'test' different sight detection system designs and make estimations on detection ranges of optical systems. In this paper we give a short overview of the physical aspects that have been implemented in the model and discuss the experimental validation of our model.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123993628","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":"Assurance regions in tracking","authors":"D. Sworder, J. E. Boyd, R. Hutchins","doi":"10.1117/12.775820","DOIUrl":"https://doi.org/10.1117/12.775820","url":null,"abstract":"An assurance region at level p, AP=p, is an area in motion space that contains the target with assigned probability p. It is on the basis of AP=p that an action is taken or a decision made. Common model-based trackers generate a synthetic distribution function for the kinematic state of the target. Unfortunately, this distribution is very coarse, and the resulting AP=p lack credibility. It is shown that a map-enhanced, multiple model algorithm reduces the tracking error and leads to a compact assurance region.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124345803","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":"Large spot size laser vibrometry insensitivity occurs in 1-D vibrations only","authors":"M. Kobold","doi":"10.1117/12.778778","DOIUrl":"https://doi.org/10.1117/12.778778","url":null,"abstract":"An envelope of two approximations forms a plane wave coherent laser vibrometry calculation set that indicates mechanisms of measured and simulated spectral \"reduction.\" Path length differences modulate large spot size continuous wave laser return leading to structural mode sensing (not a random signal issue). Calculations for sine swept and multi-modal approximations show vibrating rectangular plates constrained on all edges have return that varies substantially with low frequency vibration modes, providing modal recognition and ID not available with 1-D modes (strips or bars).","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134376988","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":"Fusing images and maps","authors":"M. Carlotto","doi":"10.1117/12.780170","DOIUrl":"https://doi.org/10.1117/12.780170","url":null,"abstract":"Spatial data sharpening techniques that fuse images and maps are described. The statistical basis of these techniques are reviewed and extended for sharpening other kinds of spatial data that can be difficult to collect in denied areas. One example is demographic data. We demonstrate the ability to derive high-resolution population maps from county or district census data and Landsat imagery that is accurate to within 5% of the true population within a test area.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":"12 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124130411","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}