Download or read book Low angle X band Radar Ground Clutter Spatial Amplitude Statistics written by J. Barrie Billingsley and published by . This book was released on 2002 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low angle Radar Land Clutter written by J. Barrie Billingsley and published by IET. This book was released on 2002 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this unique book, Billingsley solves the problem of radar land clutter by showing the reader how to design and predict the performance of radars that operate in situations where echoes from the earth's surface interfere with radar target echoes.
Download or read book Radar Ground Clutter Measurements and Models Part 1 Spatial Amplitude Statistics written by J. B. Billingsley and published by . This book was released on 1991 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: At MIT Lincoln Laboratory, we have collected a large multifrequency data base of radar ground clutter measurements from many sites. We employ our clutter data to develop clutter models. Of particular interest to us is the site-specific prediction of PPI ground clutter maps for ground-sited radars, that is, in simulating the spatial variation of ground clutter. This paper describes our measurements, and presents a statistical clutter model for spatial amplitude statistics based on depression angle, terrain type, RF frequency, and radar resolution.
Download or read book Temporal Statistics of Low Angle Ground Clutter written by H. C. Chan and published by . This book was released on 1989 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detailed knowledge of the temporal statistics of ground clutter is essential to determine the detection threshold settings so as to maximize the probability of target detection while maintaining an acceptable probability of false alarm. The performance of existing false alarm control schemes is often limited due to a lack of detailed knowledge of the ground clutter temporal statistics. In this study we analyze experimental data to characterize the temporal statistics of low-angle ground clutter in terms of the clutter's linear amplitude distribution. Effects of radar frequency, polarization, waveform resolution, land covers and wind speed on the statistics are examined. Results show that the Ricean distribution and its limiting case, the Rayleigh distribution, are appropriate models for ground clutter in steady-state wind conditions. This implies that the diffuse clutter components, which give rise to the random properties of ground clutter may be modeled as a complex Gaussian process. We found, however, that at any given time there is a fraction of the resolution cells with clutter data having nonstationary temporal statistics not well modelled by the Ricean or Rayleigh distribution. The frequency of occurrence of nonstationary clutter statistics depends on radar frequency, land cover and wind speed. Forested land cover represents the worst case scenario. Application of the results of this study to determine optimal detection threshold settings is discussed. Radar clutter; Phased array radar; S band; Canada. (edc).
Download or read book Low angle Radar Land Clutter written by J. Barrie Billingsley and published by William Andrew Pub. This book was released on 2002 with total page 703 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides information on how to design and predict the performance of radars that operate in situations where land clutter is prevalent.
Download or read book Multifrequency Measurements of Radar Ground Clutter at 42 Sites Volume 1 Principal Results written by and published by . This book was released on 1991 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report determines how ground clutter strength varies with RF frequency from VHF to X-band in ground-sited radar. These results indicate that the frequency dependence of ground clutter strength depends upon terrain type and can vary, for example, from a strongly decreasing function of frequency in forest to a strongly increasing function of frequency in farmland. Five major terrain categories are defined that encompass this dependence, namely, urban, mountains, forest, farmland, and desert. Within each terrain category, results are also shown to be dependent upon relief or roughness of the terrain and upon the depression angle at which the terrain is illuminated. The depression angle dependence is important, even for the very low angles (typically within a degree of grazing incidence) and small (typical fractional) variations in angle that occur in ground-sited radar. This report presents specific clutter strength results at each of five frequencies (VHF, UHF, L-, S-, and X-band) from each of the 42 sites at which measurements were conducted. The report then combines results from similar sites to obtain the general dependence of clutter strength versus frequency for each terrain category. clutter strengths are described in terms of moments (including the mean) and percentile levels (including the median) in measured clutter amplitude distributions resulting from cell-by-cell spatial variation over a selected large kilometer-sized macroregion of terrain at each site called the repeat sector. Measurements over the repeat sector at each site were repeated a number of times to increase the reliability of the results.
Download or read book Radar Sea Clutter written by Luke Rosenberg and published by IET. This book was released on 2021-12-17 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents comprehensive coverage of new research into sea clutter characterisation and modelling, radar performance prediction and maritime target detection. The book also includes a summary of sea-clutter scattering characteristics and datasets provided that can be used for modelling.
Download or read book X Band Radar Ground Clutter Statistics for Resolution Cells of Arbitrary Size and Shape written by and published by . This book was released on 1999 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: A procedure is developed for predicting the clutter reflectivity and probability density function of X-band radar clutter returns for resolution cells of arbitrary size and shape. The prediction uses high-resolution measurements of phase and amplitude of the ground reflections made by synthetic aperture radar (SAR) to estimate the properties of the clutter that would be observed with lower resolution radars. Clutter scene images collected by the MSTAR Program form the basis of this work. MSTAR public clutter scene data consists of spotlight mode X-band SAR images with typical resolution 0.3 x 0.3 m. Under certain assumptions, the statistics of the image pixels will approximate those of the associated clutter cells. The probability distribution of the complex pixel amplitudes is found to be significantly non-Gaussian. Larger resolution cells are constructed by coherently combining the returns from adjacent pixels. The statistical properties of clutter in these larger resolution cells is examined for a variety of cell sizes, shapes, and underlying terrain types.
Download or read book X band Radar Ground Clutter Statistics for Resolution Cells of Arbitrary Size and Shape written by James Ernstmeyer and published by . This book was released on 2001 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spectral Characteristics of Low angle Radar Ground Clutter written by and published by . This book was released on 1989 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of ground-based radars is affected by the spectral characteristics of ground clutter. Most signal processing algorithms designed to enhance detection performance are Doppler-frequency-sensitive, such as the moving target indicator filter, Doppler processor and coherent clutter map. This report gives the results of a comprehensive spectral analysis of low-angle ground clutter, using the MIT Lincoln Laboratory Phase I data and the DREO S-band clutter data. The report presents the spectral analysis of ground clutter for different bands of radar frequency; describes the data used in the spectral analysis, including both the conventional Fourier analysis and a super-resolution spectral analysis technique; gives a brief background on the maximum entropy spectral estimate; and describes the particular procedure designed to bring out the spectral characteristics of ground clutter from short time series.
Download or read book Multifrequency Measurements of Radar Ground Clutter at 42 Sites Volume 3 Appendix E written by and published by . This book was released on 1991 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report determines how ground clutter strength varies with RF frequency from VHF to X-band in ground-sited radar. This determination is accomplished by providing extensive empirical results from multifrequency clutter measurements conducted at 42 different sites widely dispersed over the North American continent. These results indicate that the frequency dependence of ground clutter strength depends upon terrain type and can vary, for example, from a strongly decreasing function of frequency in forest to a strongly increasing function of frequency in farmland. Five major terrain categories are defined that encompass this dependence, namely, urban, mountains, forest, farmland, and desert. Within each terrain category, results are also shown to be dependent upon the relief or roughness of the terrain and upon the depression angle at which the terrain is illuminated. The depression angle dependence is important, even for the very low angles (typically within a degree of grazing incidence) and small (typically fractional) variations in angle that occur in ground-sited radar. This report presents specific clutter strength results at each of five frequencies (VHF, UHF, L-, S-, and X-band) from each of the 42 sites at which measurements were conducted. The report then combines results from similar sites to obtain the general dependence of clutter strength versus frequency for each terrain category. Clutter strengths are described in terms of moments (including the mean) and percentile levels (including the median) in measured clutter amplitude distributions resulting from cell-by-cell spatial variation over a selected large kilometer-sized macroregion of terrain at each site called the repeat sector.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1992 with total page 1244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radar Ground Clutter Measurement and Models Part 2 Spectral Characteristics and Temporal Statistics written by Hing C. Chan and published by . This book was released on 1991 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of ground-based surveillance radars is affected by the spectral characteristics and the temporal statistics of ground clutter. Traditionally, ground clutter problems are treated by employing filtering techniques such as delay-line cancellers. These techniques result in a degraded detection performance of low-velocity targets. With the worsening congestion in air traffic, there is an increased demand for improved performance of low-velocity target detection. To improve the detection performance of ground-based surveillance radars for low-velocity targets, signal processing algorithms which exploit ground-clutter characteristics must be developed. This requires a thorough understanding of ground-clutter behaviour. In this paper, we report the results of the spectral and statistical analyses of low-angle ground clutter, using data of the MIT Lincoln Laboratory Phase I program and S-band coherent ground-clutter data collected by the Radar Division of the Defence research Establishment Ottawa. The results of the spectral analysis show that ground clutter, as observed by a coherent radar with a stationary antenna, comprises three components: (a) a coherent component, (b) a slow-diffuse component and (c) a fast-diffuse component. These components can be described by relatively simple models. The model parameters are functions of radar frequency, waveform resolution, land cover and wind speed.
Download or read book Millimeter wave Radar Targets and Clutter written by Gennadiĭ Petrovich Kulemin and published by Artech House. This book was released on 2003 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: This ground-breaking resource offers you a detailed treatment of EDGE and its critical role in the development of the mobile Internet. The book explains how this global radio based high-speed mobile data standard can be introduced into GSM/GPRS networks, improving data transmission speeds to support multimedia services. It enables you to become thoroughly knowledgeable of EDGE specifications and covers concepts pertaining to several domains, including RF, signal processing, digital communications and communication networks.
Download or read book Analyses of Millimeter Wave Radar Low Angle Ground Clutter Measurements for European Like and Desert Environments written by Ronald Wellman and published by . This book was released on 1996-07-01 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes millimeter wave ground based radar cross section measurements taken to support the SWOE JT&E program over two years. RCS measurements were made on selected ground clutter patches for one month and over another 43-day period at Camp Grayling, MI; and for 47 days at Yuma Proving Ground, AZ. Instruments collected data on meteorological conditions, solar flux, and soil moisture content. A wide range of atmospheric conditions was observed in Grayling over the measurement periods. The conditions in Yuma over the measurement period were relatively stable. In this report, we describe the variations in the ground based measured RCS of different clutter types over time and space for environmental conditions encountered during the three field tests. We have developed and will present an empirical model to describe these variations for the Yuma and Grayling II environments.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
