Bibliografie tematiche / Radar in aeronautics

Indice

Articoli di riviste
Tesi
Libri
Capitoli di libri
Atti di convegni
Rapporti di organizzazioni

Letteratura scientifica selezionata sul tema "Radar in aeronautics"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 27 febbraio 2023

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Radar in aeronautics".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Articoli di riviste sul tema "Radar in aeronautics"

Marks, David A., David B. Wolff, Lawrence D. Carey e Ali Tokay. "Quality Control and Calibration of the Dual-Polarization Radar at Kwajalein, RMI". Journal of Atmospheric and Oceanic Technology 28, n. 2 (1 febbraio 2011): 181–96. http://dx.doi.org/10.1175/2010jtecha1462.1.

Testo completo

Abstract (sommario):

Abstract The dual-polarization weather radar on the Kwajalein Atoll in the Republic of the Marshall Islands (KPOL) is one of the only full-time (24/7) operational S-band dual-polarimetric (DP) radars in the tropics. Through the use of KPOL DP and disdrometer measurements from Kwajalein, quality control (QC) and reflectivity calibration techniques were developed and adapted for use. Data studies in light rain show that KPOL DP measurements are of sufficient quality for these applications. While the methodology for the development of such applications is well documented, the tuning of specific algorithms to the particular regime and observed raindrop size distributions requires a comprehensive testing and adjustment period. Presented are algorithm descriptions and results from five case studies in which QC and absolute reflectivity calibration were performed and assessed. Also described is a unique approach for calibrating the differential reflectivity field when vertically pointing observations are not available. Results show the following: 1) DP-based QC provides superior results compared to the legacy Tropical Rainfall Measuring Mission (TRMM) QC algorithm (based on height and reflectivity thresholds), and 2) absolute reflectivity calibration can be performed using observations of light rain via a published differential phase–based integration technique; results are within ±1 dB compared to independent measurements. Future extension of these algorithms to upgraded Weather Surveillance Radar-1988 Doppler (WSR-88D) polarization diverse radars will benefit National Aeronautics and Space Administration’s (NASA’s) Precipitation Measurement Missions (PMM) validation programs.

Gli stili APA, Harvard, Vancouver, ISO e altri

Wang, Lei, Ming Wei, Tao Yang e Ping Liu. "Effects of Atmospheric Refraction on an Airborne Weather Radar Detection and Correction Method". Advances in Meteorology 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/407867.

Testo completo

Abstract (sommario):

This study investigates the effect of atmospheric refraction, affected by temperature, atmospheric pressure, and humidity, on airborne weather radar beam paths. Using three types of typical atmospheric background sounding data, we established a simulation model for an actual transmission path and a fitted correction path of an airborne weather radar beam during airplane take-offs and landings based on initial flight parameters and X-band airborne phased-array weather radar parameters. Errors in an ideal electromagnetic beam propagation path are much greater than those of a fitted path when atmospheric refraction is not considered. The rates of change in the atmospheric refraction index differ with weather conditions and the radar detection angles differ during airplane take-off and landing. Therefore, the airborne radar detection path must be revised in real time according to the specific sounding data and flight parameters. However, an error analysis indicates that a direct linear-fitting method produces significant errors in a negatively refractive atmosphere; a piecewise-fitting method can be adopted to revise the paths according to the actual atmospheric structure. This study provides researchers and practitioners in the aeronautics and astronautics field with updated information regarding the effect of atmospheric refraction on airborne weather radar detection and correction methods.

Gli stili APA, Harvard, Vancouver, ISO e altri

Matthee, Retha, John R. Mecikalski, Lawrence D. Carey e Phillip M. Bitzer. "Quantitative Differences between Lightning and Nonlightning Convective Rainfall Events as Observed with Polarimetric Radar and MSG Satellite Data". Monthly Weather Review 142, n. 10 (19 settembre 2014): 3651–65. http://dx.doi.org/10.1175/mwr-d-14-00047.1.

Testo completo

Abstract (sommario):

Abstract To increase understanding of the relationships between lightning and nonlightning convective storms, lightning observations from the National Aeronautics and Space Administration (NASA) African Monsoon Multidisciplinary Analyses (NAMMA) campaign were analyzed with Meteosat Second Generation (MSG) geostationary satellite and S-band NASA Polarimetric Doppler Weather Radar (NPOL) data. The study’s goal was to analyze the time evolution of infrared satellite fields and ground-based polarimetric radar during NAMMA to quantify relationships between satellite and radar observations for lightning and nonlightning convective clouds over equatorial Africa. Using NPOL data, very low-frequency arrival time difference lightning data, and MSG Spinning Enhanced Visible and Infrared Imager observations, the physical attributes of growing cumulus clouds, including ice mass production, updraft strength, cloud depth, and cloud-top glaciation were examined. It was found that, on average, the lightning storms had stronger updrafts (seen in the satellite and radar fields), which lead to the formation of deeper clouds (seen in the satellite and radar fields) and subsequently much more ice in the mixed-phase region (as confirmed in radar observations), as well as much more nonprecipitating ice in the top 1 km of the cloud (as quantified in both satellite and radar fields) than the nonlightning storms. Computed radar-derived ice masses in cumulus clouds verifies the traditional MSG indicators of cloud-top glaciation, while NPOL verifies internal structures (i.e., large amounts of graupel) where satellite and radar show strong updrafts.

Gli stili APA, Harvard, Vancouver, ISO e altri

Tokay, Ali, Leo Pio D’Adderio, David A. Marks, Jason L. Pippitt, David B. Wolff e Walter A. Petersen. "Comparison of Raindrop Size Distribution between NASA’s S-Band Polarimetric Radar and Two-Dimensional Video Disdrometers". Journal of Applied Meteorology and Climatology 59, n. 3 (marzo 2020): 517–33. http://dx.doi.org/10.1175/jamc-d-18-0339.1.

Testo completo

Abstract (sommario):

AbstractThe ground-based-radar-derived raindrop size distribution (DSD) parameters—mass-weighted drop diameter Dmass and normalized intercept parameter NW—are the sole resource for direct validation of the National Aeronautics and Space Administration (NASA) Global Precipitation Measurement (GPM) mission Core Observatory satellite-based retrieved DSD. Both Dmass and NW are obtained from radar-measured reflectivity ZH and differential reflectivity ZDR through empirical relationships. This study uses existing relationships that were determined for the GPM ground validation (GV) program and directly compares the NASA S-band polarimetric radar (NPOL) observables of ZH and ZDR and derived Dmass and NW with those calculated by two-dimensional video disdrometer (2DVD). The joint NPOL and 2DVD datasets were acquired during three GPM GV field campaigns conducted in eastern Iowa, southern Appalachia, and western Washington State. The comparative study quantifies the level of agreement for ZH, ZDR, Dmass, and log(NW) at an optimum distance (15–40 km) from the radar as well as at distances greater than 60 km from radar and over mountainous terrain. Interestingly, roughly 10%–15% of the NPOL ZH–ZDR pairs were well outside the envelope of 2DVD-estimated ZH–ZDR pairs. The exclusion of these pairs improved the comparisons noticeably.

Gli stili APA, Harvard, Vancouver, ISO e altri

D’Adderio, Leo Pio, Gianfranco Vulpiani, Federico Porcù, Ali Tokay e Robert Meneghini. "Comparison of GPM Core Observatory and Ground-Based Radar Retrieval of Mass-Weighted Mean Raindrop Diameter at Midlatitude". Journal of Hydrometeorology 19, n. 10 (1 ottobre 2018): 1583–98. http://dx.doi.org/10.1175/jhm-d-18-0002.1.

Testo completo

Abstract (sommario):

Abstract One of the main goals of the National Aeronautics and Space Administration (NASA) Global Precipitation Measurement (GPM) mission is to retrieve parameters of the raindrop size distribution (DSD) globally. As a standard product of the Dual-Frequency Precipitation Radar (DPR) on board the GPM Core Observatory satellite, the mass-weighted mean diameter Dm and the normalized intercept parameter Nw are estimated in three dimensions at the resolution of the radar. These are two parameters of the three-parameter gamma model DSD adopted by the GPM algorithms. This study investigates the accuracy of the Dm retrieval through a comparative study of C-band ground radars (GRs) and GPM products over Italy. The reliability of the ground reference is tested by using two different approaches to estimate Dm. The results show good agreement between the ground-based and spaceborne-derived Dm, with an absolute bias being generally lower than 0.5 mm over land in stratiform precipitation for the DPR algorithm and the combined DPR–GMI algorithm. For the DPR–GMI algorithm, the good agreement extends to convective precipitation as well. Estimates of Dm from the DPR high-sensitivity (HS) Ka-band data show slightly worse results. A sensitivity study indicates that the accuracy of the Dm estimation is independent of the height above surface (not shown) and the distance from the ground radar. On the other hand, a nonuniform precipitation pattern (interpreted both as high variability and as a patchy spatial distribution) within the DPR footprint is usually associated with a significant error in the DPR-derived estimate of Dm.

Gli stili APA, Harvard, Vancouver, ISO e altri

Yin, Mengtao, e Cheng Yuan. "Exploring the Environmental Conditions of Snow Particles Using Spaceborne Triple-Frequency Radar Measurements over Ocean". Remote Sensing 14, n. 21 (1 novembre 2022): 5512. http://dx.doi.org/10.3390/rs14215512.

Testo completo

Abstract (sommario):

The environmental conditions of snow particles with different particle sizes and bulk effective densities over the ocean are explored using a coincidence dataset of National Aeronautics and Space Administration (NASA) CloudSat Cloud Profiling Radar (CPR) and Global Precipitation Mission (GPM) Dual-frequency Precipitation Radar (DPR). Observed triple-frequency radar signatures for snow particles over the ocean are firstly derived. Based on modeled triple-frequency signatures for various snow particles, DFR Ku/Ka and the ratio of DFR Ku/Ka to DFR Ku/W from observations are selected to indicate the snow particle size and bulk effective density, respectively. The dependences of two indicators on temperature, relative humidity and cloud liquid water content are presented. The snow particle size range becomes wider at warmer temperatures, higher relative humidities or lower cloud liquid water contents. At cold temperatures, low relative humidities or high cloud liquid water contents, large snow particles are prevalent. At high cloud liquid water contents, the riming process mainly contributes to the increase in snow particle bulk effective density. When supersaturation occurs, a large portion of snow particles have large sizes and low bulk effective densities at cold temperatures. This study can improve the understanding of snow microphysics and demonstrate the potential of spaceborne radar measurements in global snowfall retrievals.

Gli stili APA, Harvard, Vancouver, ISO e altri

Wijesundara, Shanka N., e Joel T. Johnson. "Physics-Based Forward Modeling of Ocean Surface Swell Effects on SMAP L1-C NRCS Observations". Sensors 22, n. 2 (17 gennaio 2022): 699. http://dx.doi.org/10.3390/s22020699.

Testo completo

Abstract (sommario):

This paper examines the impact of ocean surface swell waves on near-coastal L-band high-resolution synthetic aperture radar (SAR) data collected using the National Aeronautics and Space Administration’s (NASA) Soil Moisture Active/Passive (SMAP) radar at 40° incidence angle. The two-scale model and a more efficient off-nadir approximation of the second-order small-slope-approximation are used for co- and cross-polarized backscatter normalized radar cross-section (NRCS) predictions of the ocean surface, respectively. Backscatter NRCS predictions are modeled using a combined wind and swell model where wind-driven surface roughness is characterized using the Durden–Vesecky directional spectrum, while swell effects are represented through their contribution to the long wave slope variance (mean-square slopes, or MSS). The swell-only MSS is numerically computed based on a model defined using the JONSWAP spectrum with parameters calculated using the National Data Buoy Center and Wave Watch III data. The backscatter NRCS model is further refined to include fetch-limited and low-wind corrections. The results show an improved agreement between modeled and observed HH-polarized backscatter NRCS when swell effects are included and indicate a relatively larger swell impact on L-band compared to higher radar frequencies. Preliminary investigations into the potential swell retrieval capabilities in the form of excess MSS are encouraging, however further refinements are required to make broadly applicable conclusions.

Gli stili APA, Harvard, Vancouver, ISO e altri

Liao, Liang, Robert Meneghini, Toshio Iguchi e Ali Tokay. "Characteristics of DSD Bulk Parameters: Implication for Radar Rain Retrieval". Atmosphere 11, n. 6 (25 giugno 2020): 670. http://dx.doi.org/10.3390/atmos11060670.

Testo completo

Abstract (sommario):

With the use of 213,456 one-minute measured data of droplet-size distribution (DSD) of rain collected during several National Aeronautics and Space Administration (NASA)-sponsored field campaigns, the relationships between rainfall rate R, mass-weighted diameter Dm and normalized intercept parameter Nw of the gamma DSD are studied. It is found, based on the simulations of the gamma DSD model, that R, Dm and Nw are closely interrelated, and that the ratio of R to Nw is solely a function of Dm, independent of the shape factor μ of the gamma distribution. Furthermore, the model-produced ratio agrees well with those from the DSD data. When a power-law equation is applied to fit the model data, we have: R = aN w D m b , where a = 1.588 × 10 − 4 , b = 4.706 . Analysis of two-parameter relationships such as R–Dm, Nw–R and Nw–Dm reveals that R and Dm are moderately correlated while Nw and Dm are negatively correlated. Nw and R, however, are uncorrelated. The gamma DSD model also reveals that variation of R–Dm relation is caused primarily by Nw. For the application of the Ku- and Ka-band dual-frequency radar for the retrieval of the DSD bulk parameters as well as the specific radar attenuations, the study is carried out to relate the dual-frequency radar reflectivity factors to the DSD and attenuation parameters.

Gli stili APA, Harvard, Vancouver, ISO e altri

Owerko, Tomasz, Przemysław Kuras e Łukasz Ortyl. "Atmospheric Correction Thresholds for Ground-Based Radar Interferometry Deformation Monitoring Estimated Using Time Series Analyses". Remote Sensing 12, n. 14 (12 luglio 2020): 2236. http://dx.doi.org/10.3390/rs12142236.

Testo completo

Abstract (sommario):

Ground-based radar interferometry (GBSAR) is a useful method to control the stability of engineering objects and elements of geographical spaces at risk of deformation or displacement. To secure accurate and credible measurement results, it is crucial to consider atmospheric conditions as they influence the corrections to distance measurements. These conditions are especially important considering the radar bandwidth used. Measurements for the stability of engineering objects are not always performed in locations where meteorological monitoring is prevalent; however, information about the range of variability in atmospheric corrections is always welcome. The authors present a hybrid method to estimate the probable need of atmospheric corrections, which allows partly eliminating false positive alarms of deformations as caused by atmospheric fluctuations. Unlike the numerous publications on atmospheric reductions focused on the current state of the atmosphere, the proposed solution is based on applying a classic machine learning algorithm designed for the SARIMAX (Seasonal Autoregressive Integrated Moving Average with covariate at time) time series data model for satellite data shared by NASA (National Aeronautics and Space Administration) during the Landsat MODIS (Moderate Resolution Imaging Spectroradiometer) mission before performing residual estimation during the monitoring phase. Example calculations (proof of concept) were made for ten-year satellite data covering a region for experimental flood bank stability observations as performed using the IBIS-L (Image by Interferometric Survey—Landslide) radar and for target monitoring data (ground measurements).

Gli stili APA, Harvard, Vancouver, ISO e altri

Adirosi, Elisa, Luca Baldini e Ali Tokay. "Rainfall and DSD Parameters Comparison between Micro Rain Radar, Two-Dimensional Video and Parsivel2 Disdrometers, and S-Band Dual-Polarization Radar". Journal of Atmospheric and Oceanic Technology 37, n. 4 (aprile 2020): 621–40. http://dx.doi.org/10.1175/jtech-d-19-0085.1.

Testo completo

Abstract (sommario):

AbstractA well-designed deployment of well-maintained surface instruments as well as abundant rainfall provided an excellent dataset with which to evaluate the Micro Rain Radar (MRR) performance for estimating raindrop size distribution (DSD) and its integral rainfall parameters with respect to the consolidated devices during the Iowa Flood Studies (IFloodS) field campaign. The MRR was collocated with two-dimensional video disdrometer (2DVD) and Autonomous Parsivel2 Unit (APU) at three different sites located at 5–70-km distances from the National Aeronautics and Space Administration’s S-band dual-polarization Doppler radar (NPOL). A comparative study between MRR, 2DVD, APU, and NPOL was conducted including all rainy minutes as well as minutes of stratiform rain and convective rain. Considering 2DVD as a primary reference, a good agreement was evident for reflectivity between MRR’s lowest reliable height and 2DVD with an absolute bias of less than 2 dB even in convective rain except for one site. For rainfall rate, the percent absolute bias between MRR and 2DVD ranged between 25% and 35% in stratiform rain and about 10% higher in convective rain. Agreement for mean mass-weighted raindrop diameter was good (bias less than 0.1 mm), whereas MRR overestimated the normalized intercept parameter of the gamma DSD [mean bias among the three sites was −0.13 log(mm−1 m−3)]. The agreement between MRR and APU was slightly worse than the one between MRR and 2DVD. When the horizontal and differential reflectivities of NPOL were compared with the ones derived from the MRR DSD resampled within the radar volume, we found an absolute bias of approximately 3 and 0.4 dB, respectively.

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Tesi sul tema "Radar in aeronautics"

Miller, Samuel(Samuel John). "Object tracking in mmWave radar networks". Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127079.

Testo completo

Abstract (sommario):

Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 71-87).
Location-aware devices enable new services such as localization and tracking of objects within existing wireless communication networks like cellular mobile, Wi-Fi, and radio. To ensure these services are also available in the evolving millimeter wave (mmWave) communication infrastructure, it is important to develop algorithms that enable mmWave devices, like radars and 5G nodes, to localize and track objects. The main challenges that these algorithms must address is localizing objects that are not carrying sensing equipment, synchronizing devices exclusively via the mmWave band, and solving a data association uncertainty problem to reliably track objects of interest. Our development of the Multistatic Networking with mmWave Radar Arrays for Positioning (MiNiMAP) system solved these challenges by implementing mmWave processing in a multistatic network, scheduling, and radar synchronization algorithms. Through the use of these three algorithms in addition to Bayesian filtering, MiNiMAP is capable of tracking a single object with a network of mmWave radars. Indoor localization experiments validate MiNiMAP's overall system performance and the impact of each algorithm.
by Samuel Miller.
S.M.
S.M. Massachusetts Institute of Technology, Department of Aeronautics and Astronautics

Gli stili APA, Harvard, Vancouver, ISO e altri

Reynolds, Obie D. "Life cycle analysis of a radar system". Master's thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12232009-020224/.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Marais, Karen 1973. "The development and analysis of Scanned Pattern Interferometric Radar". Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/82229.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Aqui, Paula S. (Paula Simone). "Meteorological effects on the accuracy of the measurement of radar cross sections". Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/43127.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Berisset, Philippe. "Simulation of millimeter wave radar return from a three dimensional environmental scene". Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/49905.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Hacker, Troy L. (Troy LeRoy) 1976. "Performance analysis of a space-based GMTI radar system using separated spacecraft interferometry". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9088.

Testo completo

Abstract (sommario):

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2000.
Includes bibliographical references (p. 153-156).
The development of a model to assess the radar performance capabilities of a sparse aperture space-based GMTI radar system is presented. Airborne radars have provided reliable detection of moving targets for many years. Recent technological advancements have allowed the deployment of radar systems in space to improve global coverage. Additional radar performance benefits from space-based platforms are made possible with clusters of collaborative microsatellites. Using quantitative capability metrics, specifically the probability of detection and the minimum detectable velocity, the performance of the radar system can be modeled to enable effective and unbiased comparison of candidate system architectures. A design study based on the space-based GMTI radar reference mission for the Air Force's TechSat 21 program was conducted to identify viable system design configurations that satisfy specific radar performance requirements. A comprehensive analysis of the cost, reliability, and performance considerations for the complete TechSat 21 system is proposed.
by Troy L. Hacker.
S.M.

Gli stili APA, Harvard, Vancouver, ISO e altri

Wickert, Douglas P. (Douglas Paul). "Space based radar--system architecture design and optimization for a space-based replacement to AWACS". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10513.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Reid, David Charles. "Improved aircraft flight parameter estimation based on passive acoustic techniques using time-frequency methods". Thesis, Queensland University of Technology, 1997.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Davis, Bradley A. "A clutter power computation procedure for airborne Doppler radar". Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53722.

Testo completo

Abstract (sommario):

This report presents a general procedure for estimating the average clutter power received by an airborne Doppler radar as a function of time and frequency. Its purpose is to construct the received power waveform at the output of a matched filter for use in the development of clutter maps related to Doppler signal processing. In developing the algorithm, several of its features are given close examination; this includes a numerical and analytical justification for the azimuth to Doppler coordinate transformation, and the power spectrum returned to the airborne Doppler radar from the surface it illuminates. This algorithm produces a continuous power returned waveform versus time. Hence, this algorithm has the flexibility to accept any surface radar cross section, antenna gain, and pulse type (a matched filter receiver is assumed) as a function of range and azimuth. It was discovered that the algorithm could be executed with significantly less computer time if the integration surface area was reduced by exploiting some physical insight. In addition, it was discovered through example that the refracting effects of the Earth's atmosphere become important as the radar's beam approaches the horizon. Finally, return power waveforms are studied for two different situations: near nadir pointing, and near horizon pointing. The manner in which the matched filter ambiguity function and the spectrum of backscattered power combine to produce these waveforms is examined.
Master of Science

Gli stili APA, Harvard, Vancouver, ISO e altri

Volpe, Kyle Clarke. "Application of the backward-smoothing extended Kalman filter to attitude estimation and prediction using radar observations". Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/51646.

Testo completo

Abstract (sommario):

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2009.
Includes bibliographical references (p. 317-322).
The Lincoln Attitude Estimation System (LAES), a new tool being developed for the Space Situational Awareness Group (SSAG) at MIT Lincoln Laboratory, integrates several existing hardware and software systems, with a backward-smoothing extended Kalman filter (BSEKF). LAES is intended to determine the rotational motion of a freely tumbling spacecraft from a sequence of discrete-time radar images. The raw range-Doppler returns are collected using a ground-based sensor, which is owned and operated by the SSAG, and processed into a set of range/cross-range images. A three-dimensional geometric model is, through computer graphics procedures, displayed on top of the two-dimensional radar images, enabling an analyst to rotate (and scale in cross-range) the model in order to align it to the object's image. Therefore, the orthographic projection matrix that the computer graphics procedures computed to display the computer model, simultaneously describes the projection of the object onto the radar image plane. These measurements are essentially corrections to a nominal or baseline motion which had to be assumed in order to generate the images in the first place. Combining the reference motion, which describes the orientation of the image plane in inertial space, with the sequence of rotations describing the attitude of the spacecraft within the image plane, yields the final set of attitude measurements which are then passed to the BSEKF for processing.
(cont.) The existing free motion software currently in use within the Space Situational Awareness Group makes two critical assumptions: 1) that that the spacecraft is a symmetric rigid body and 2) that there are no disturbance torques acting on the spacecraft during the imaging period. The Lincoln Attitude Estimation System removes these simplifying assumptions in favor of a more flexible approach which is better suited for long-term studies of rigid body motion. Accordingly, several additions have been made to the backward-smoothing extended Kalman filter, including the addition of environmental torque models and an algorithm which generates an initial estimate for the inertia tensor using the same geometric model used in the image-model matching process. The BSEKF solves a nonlinear smoothing problem for the current and past sample intervals using iterative numerical techniques. This approach retains the nonlinearities of a fixed number of stages that precede the time of interest, and processes information from earlier stages in an approximate manner. The algorithm has been tested using simulated and actual data from a challenging spacecraft attitude estimation problem in which there is significant measurement noise, poor initial state estimates, and highly nonlinear system dynamics. The filter compensates for this uncertainty through concurrent estimation of the attitude and moment of inertia parameters. The filter has been demonstrated to accurately and reliably converge on a motion solution in both types of test cases.
by Kyle Clarke Volpe.
S.M.

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Libri sul tema "Radar in aeronautics"

Morris, G. V. Airborne pulsed Doppler radar. Norwood, MA: Artech House, 1988.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

1935-, Morris G. V., e Harkness L. 1956-, a cura di. Airborne pulsed doppler radar. 2^a ed. Boston: Artech House, 1996.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Barr, James C. Airborne weather radar: A user's guide. Ames: Iowa State University Press, 1993.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Mack, A. R. Four band airborne radar imagery for agricultural applications. Ottawa: Agriculture Canada, Research Branch, 1986.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

W, Kamerman Gary, e Society of Photo-optical Instrumentation Engineers., a cura di. Laser radar technology and applications II: 23-25 April 1997, Orlando, Florida. Bellingham, Wash., USA: SPIE, 1997.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

SC-173, RTCA (Firm). Minimum operational performance standards for airborne weather radar with forward-looking windshear capability. Washington, D.C. (1140 Connecticut Ave., Northwest, Suite 1020 Washington 20036: RTCA, 1993.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

A, Anisimov V., Finkelʹshteĭn M. I e Rīgas civīlās aviācijas inženieru institūts., a cura di. Teorii͡a︡ i tekhnika radiolokat͡s︡ii, radionavigat͡s︡ii i radiosvi͡a︡zi v grazhdanskoĭ aviat͡s︡ii: Mezhvuzovskiĭ sbornik nauchnykh trudov. Riga: RIO RKIIGA, 1988.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Scott, R. E. Air-to-air radar flight testing. Neuilly-sur-Seine: AGARD, 1988.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

European Conference on Synthetic Aperture Radar (5th 2004 Ulm, Germany). EUSAR 2004: Proceedings : 5th European Conference on Synthetic Aperture Radar : May 25-27, 2004, Ulm, Germany. Berlin: VDE-Verlag, 2004.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

European, Conference on Synthetic Aperture Radar (1996 Königswinter Germany). EUSAR '96, European Conference on Synthetic Aperture Radar, 26-28 March 1996, Königswinter, Germany. Berlin: VDE-Verlag, 1996.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Più fonti

Capitoli di libri sul tema "Radar in aeronautics"

Emmanuel, Uche. "Review of Agricultural Unmanned Aerial Vehicles (UAV) Obstacle Avoidance System". In Aeronautics - New Advances. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.103037.

Testo completo

Abstract (sommario):

Unmanned aerial vehicles (UAVs) are being used for commercial, scientific, agricultural and infrastructural enhancement to alleviate maladies. The objective of this chapter is to review existing capabilities and ongoing studies to overcome difficulties associated with the deployment of the agricultural unmanned aerial vehicle in obstacle-rich farms for pesticides and fertilizer application. By review of various literature, it is apparent that the potential for real-time and near real-time exists but the development of technology for quality imagery and rapid processing leading to real-time response is needed. The Infrared, time of flight and millimeter wavelength radar sensors for detecting farm and flight environment obstacles appear promising. The autonomous mental development algorithm, and the simultaneous localization and mapping technology are, however, ahead of others in achieving autonomous identification of obstacles and real-time obstacle avoidance. They are, therefore, found fit for further studies and development for deployment on agricultural unmanned aerial vehicles for obstacle-rich farms.

Gli stili APA, Harvard, Vancouver, ISO e altri

Atti di convegni sul tema "Radar in aeronautics"

Bowdle, David A., e Daniel E. Fitzjarrald. "THE GLObal Backscatter Experiment (GLOBE) Program". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/clr.1987.wa1.

Testo completo

Abstract (sommario):

NASA has recently initiated a major program, the GLObal Backscatter Experiment (GLOBE), to measure atmospheric aerosol backscatter and related aerosol physical, chemical, and optical properties. The comprehensive aerosol data base from this effort will be used to develop a global-scale model of the typical magnitudes and the spatial / temporal variability of aerosol backscatter. The model will be used in design and simulation studies for NASA’s (National Aeronautics and Space Administration) Doppler Lidar Atmospheric Wind Sounder (LAWS) (Baker and Curran, 1985), which is planned for deployment to low earth orbit in the mid 1990’s.

Gli stili APA, Harvard, Vancouver, ISO e altri

Bowdle, David A., Jeffry Rothermel, Steven F. Williams e James E. Arnold. "The GLObal Backscatter Experiment (GLOBE) Pacific Survey Mission". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/clr.1991.fa2.

Testo completo

Abstract (sommario):

The National Aeronautics and Space Administration (NASA) conducted the GLObal Backscatter Experiment (GLOBE) survey missions on a NASA DC-8 aircraft over the central and near-coastal Pacific Ocean during November 6 - 30, 1989 (GLOBE I) and May 13 - June 5, 1990 (GLOBE II). These missions were designed to study the optical, physical, and chemical properties of atmospheric aerosols. Particular emphasis was given to the magnitude and spatial variability of aerosol backscatter coefficients (β, m−1sr−1) at mid-infrared (9-11 µm) and mid-visible to near-infrared (0.5-1.5 µm) wavelengths. Both missions concentrated on the remote middle and upper troposphere, where these aerosol properties are poorly understood.

Gli stili APA, Harvard, Vancouver, ISO e altri

Srivastava, Vandana, Maurice Jarzembski, Antony D. Clarke, John Porter e Jeffry Rothermel. "Comparison of Backscatter Measurements with Aerosol Microphysics: Wavelength Dependence". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/clr.1991.wd6.

Testo completo

Abstract (sommario):

The GLObal Backscatter Experiment (GLOBE) flight survey missions were sponsored by the National Aeronautics Space Administration (NASA) during 1989 and 1990, involving a series of flights over the Pacific Ocean. Lidar backscatter and aerosol microphysics measurements were made simultaneously. Among the complement of instruments on board the NASA DC-8 aircraft were two continuous wave (CW), focused, CO2 Doppler lidars operating at 9.1μm and 10.6μm, and a thermally pre-conditioned Laser Optical Particle Counter (LOPC). Aerosol backscatter can be theoretically modeled from the measured aerosol microphysics data by using Mie theory (Mie, 1908). Comparison of this theoretical backscatter with direct lidar backscatter measurements will yield better aerosol models for various atmospheric conditions. Aerosol microphysics model can then be used to predict backscatter at other wavelengths for which lidar measurements are not currently available.

Gli stili APA, Harvard, Vancouver, ISO e altri

Brook, A., E. Cristofani, M. Vandewal, C. Matheis e J. Jonuscheit. "3-D radar image processing methodology for Non-Destructive Testing of aeronautics composite materials and structures". In 2012 IEEE Radar Conference (RadarCon). IEEE, 2012. http://dx.doi.org/10.1109/radar.2012.6212248.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Rothermel, Jeffry, William D. Jones, Vandana Srivastava, Maurice Jarzembski e Diana Hampton. "Remote Tropospheric Backscatter Measurements at 9.1 and 10.6 Micrometers with Airborne Focused Doppler Lidars". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/clr.1991.fa5.

Testo completo

Abstract (sommario):

Over the past ten years, interest has grown in characterizing atmospheric aerosol backscatter levels in response to escalating interest in several proposed satellite-borne, lidar-based sensors. Measurements of some primary atmospheric parameter will be obtained from signals backscattered from micrometer-size aerosols. An example is the Laser Atmospheric Wind Sounder (LAWS) under development by the National Aeronautics and Space Administration (NASA), Marshall Space Flight Center (MSFC) as part of the NASA Earth Observing System (EOS) earth system science initiative (Curran, 1987). LAWS is intended to provide global tropospheric wind measurements using Doppler-shifted signals from aerosols, which act as passive wind tracers. The accuracy of the wind estimates is a function of the signal strength, which in turn is a function of the aerosol backscatter coefficient. Therefore, LAWS performance will depend in part on the spatial distribution of aerosols, and associated physical, chemical, and optical properties.

Gli stili APA, Harvard, Vancouver, ISO e altri

Allario, Frank, Charles E. Byvik e Norman P. Barnes. "Solid State Laser Technology for Coherent Lidar". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/clr.1987.ma2.

Testo completo

Abstract (sommario):

As part of the National Aeronautics and Space Administration's (NASA) Space Station program, a lidar facility is being planned to conduct a series of scientific experiments from a polar orbiting platform. The thrust of these experiments is to improve our understanding of atmospheric chemistry and dynamics, altimetry, and meteorology. A number of scientific experiments were recently developed by a panel of scientists and lidar technologists and included both atmospheric backscatter (Lidar) and Differential Absorption and Lidar (DIAL) experiments. The major investigations to be conducted include measurements of the vertical profiles of atmospheric aerosols, the height of the Planetary Boundary Layer (PBL), the distribution of cirrus clouds, vertical profiles of water vapor in the lower and upper atmosphere, vertical profiles of ozone, and measurements of the vertical profiles of pressure and temperature. These experiments were developed by the Lidar Atmospheric Sounder and Altimetry (LASA) panel, and have been summarized in a NASA document.

Gli stili APA, Harvard, Vancouver, ISO e altri

Rothermel, Jeffry, J. Michael Vaughan e David A. Bowdle. "Algorithm to Calculate Aerosol Backscatter from Airborne CW Focused CO2 Doppler Lidar Measurements". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/clr.1987.tua4.

Testo completo

Abstract (sommario):

Since 1981 the Royal Signals and Radar Establishment (RSRE) and the Royal Aircraft Establishment (RAE), United Kingdom, have made vertical and horizontal sounding measurements of aerosol backscatter cross-section using an airborne continuous-wave (CW) focused CO2 Doppler lidar, the Laser True Airspeed System (LATAS). The LATAS measures both the backscatter cross-section and line-of-sight velocity (with respect to the LATAS) of naturally-occurring micrometer-sized aerosol particles. These measurements are an important part of a data base for the development of a global-scale model of aerosol backscatter at CO2 wavelengths (Bowdle, 1986). In turn, the model is used in the design and simulated operation of NASA’s (National Aeronautics and Space Administration) prospective Lidar Atmospheric Wind Sounder (LAWS) (Baker and Curran, 1985). The performance of LAWS in providing global wind measurements will be critically dependent upon the signal-to-noise ratio (SNR) of the received signal, which is primarily a function of the concentration and backscatter efficiency of aerosols in the sample volume. This report describes the computer algorithm used to convert the LATAS measurements of backscatter signal into estimates of SNR and backscatter coefficient.

Gli stili APA, Harvard, Vancouver, ISO e altri

Zhang, Xiao-lin, Wen-ting You, Qiang Guo e He-yang Cao. "Recognition method studies for radar and communication signals based on spectral correlation". In 2010 3rd International Symposium on Systems and Control in Aeronautics and Astronautics (ISSCAA 2010). IEEE, 2010. http://dx.doi.org/10.1109/isscaa.2010.5633036.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Linnehan, Robert. "Profiles in industry: General Atomics Aeronautical Systems Inc." In Radar Sensor Technology XXII, a cura di Kenneth I. Ranney e Armin Doerry. SPIE, 2018. http://dx.doi.org/10.1117/12.2305176.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Zak, Jan, e Vaclav Papez. "Target position determining in aeronautical issues". In 2017 18th International Radar Symposium (IRS). IEEE, 2017. http://dx.doi.org/10.23919/irs.2017.8008243.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Rapporti di organizzazioni sul tema "Radar in aeronautics"

Lammers, Gary, e Mel Lammers. Technical Raster Transfer Installation Drawing: Waveguide LPCR-130-2 Radar. Submitted By: Lockheed Aeronautical Systems. Supporting: WR-ALC/TILCA's EDCARS Program Contract Number F33657-90-C-0071-P000l3BL2. MIL-STD-1840A, MIL-R-28002A (Raster). Quick Short Test Report. Fort Belvoir, VA: Defense Technical Information Center, agosto 1994. http://dx.doi.org/10.21236/ada312997.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Offriamo sconti su tutti i piani premium per gli autori le cui opere sono incluse in raccolte letterarie tematiche. Contattaci per ottenere un codice promozionale unico!