Download or read book Passive Radar Clutter Modeling and Emitter Selection for Ground Moving Target Indication written by James R. Lievsay and published by . This book was released on 2017 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Airborne Radar Technique for Moving target Detection Location and Tracking written by John K. Schindler and published by . This book was released on 1973 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: A novel technique for detecting, locating, and tracking moving targets from an airborne radar platform is described and analyzed. The technique uses the generally dissimilar linear doppler frequency modulated signals from moving targets and stationary ground clutter. A matched filter processor is defined and its resolution and ambiguity properties studied as function processor parameters. Sub-clutter visibility of the processor is then determined. Two techniques for digitally implementing the processor are discussed and the computational efficiencies briefly analyzed. Finally, target angular position can be determined using phase monopulse. It is then shown that target velocity--both ground speed and target heading--can be determined from radar observables. (Author).
Download or read book Passive Radars on Moving Platforms written by Diego Cristallini and published by IET. This book was released on 2023-05-23 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an exhaustive overview of techniques, challenges and applications that are enabled when a passive radar is operated from a moving platform.
Download or read book Low Angle Radar Land Clutter written by J. Barrie Billingsley and published by William Andrew. This book was released on 2002-04-01 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt: A necessary reference for all radar engineers or analysts including many levels of managers, advisors and decision makers in the U.S. and worldwide radar industry. Directly useful in both military (DOD) and civilian (FAA) applications. The result of 20 years of research at MIT Lincoln Lab, this book is of the most significant tehcnological consequence for the industry. It actually solves the problem of low angle radar land clutter by showing the reader how to design and predict the performance of radars that operate in situations where land clutter prevalent. Radar land clutter constitutes the unwanted radar echoes returned from the earth's surface that compete against and interfere with the desired echoes returned by targets such as aircraft and other moving and stationary targets. The ability to accurately predict the effects of land clutter in surface radar has been an unsolved problem for many years. This book is comprehensive in addressing the topic, containing many interrelated results, each important in its own right. It unifies and integrates all the results so as to create a comprehensive, innovative, and unequaled work. The results of this book directly enable the reader to predict land clutter effects in surface radar. Modern military aircraft deliberately fly low to hide their presence from radars that are also dealing with land clutter. Depending on the terrain, the performance of the radar varies greatly from very good to very poor. This book helps radar engineers provide accurate assessments of ground clutter, thus bringing their ability to detect and operate against low flying aircraft to a much higher and much more consistent level.
Download or read book An Introduction to Passive Radar written by Hugh D. Griffiths and published by Artech House. This book was released on 2017-02-28 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developed by recognized experts in the field, this first-of-its-kind resource introduces the basic principles of passive radar technology and provides an overview of recent developments in this field and existing real passive radar systems. This book explains how passive radar works, how it differs from the active type, and demonstrates the benefits and drawbacks of this novel technology. Properties of illuminators, including ambiguity functions, digital vs. analog, digitally-coded waveforms, vertical-plane coverage, and satellite-borne and radar illuminators are explored. Readers find practical guidance on direct signal suppression, passive radar performance prediction, and detection and tracking. This book provides concrete examples of systems and results, including analog TV, FM radio, cell phone base stations, DVB–T and DAB, HF skywave transmissions, indoor WiFi, satellite-borne illuminators, and low-cost scientific remote sensing. Future developments and applications of passive radar are also presented.
Download or read book Ground Moving Target Indication Radar with Small Antenna Arrays written by C. P. Banahan and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ground Moving Target Indication Radar with Small Antenna Arrays written by Christopher Peter Banahan and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Approaches to Ground Moving Target Indicator Radar written by Michael Richard Riedl and published by . This book was released on 2016 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasing the resolution of radar imaging and ground moving target indicator (GMTI) systems puts a stress on both hardware and processing limitations. Hardware must be able to handle the transfer of the large amounts of data generated. Additionally, the processing must be robust to any heterogeneity of the data that is introduced by collecting returns from large swaths. This dissertation presents system architectures and knowledge-aided processing techniques to combat the large data rates and data heterogeneity. Ground moving target indicator radar techniques for airborne platforms require spatial and Doppler signal diversity for separating the returns of moving targets from the returns of ground clutter. The traditional use of multiple receive antennas for jointly imaging a scene and detecting moving objects is prohibited by the system bottleneck at the data down-link. We present a frequency division multiple access, multiple-transmit single-receive radar architecture, with associated waveform design and data processing procedure. The proposed approach is demonstrated to jointly provide imaging and GMTI modalities while maintaining the data rate to that of a single antenna imaging system. Heterogeneity of the radar backscatter data degrades detection performance by biasing statistical parameters estimated from the data. A GMTI processing technique, known as space-time adaptive processing (STAP), requires estimation of the space-time covariance of the clutter for use in a generalized likelihood ratio test. Consequently, the performance of STAP is related to the quality of the estimated clutter covariance matrix; however, in practice it is common for the data to be limited, contaminated, and heterogeneous. In this dissertation, we introduce and evaluate two estimators for the clutter covariance and a purely Bayesian detection scheme. A Bayesian model is postulated for the angle/Doppler scene to incorporate approximate prior knowledge of the terrain height and the platform kinematics. Posterior probabilities computed using the model are then used to either estimate a covariance matrix or directly report posterior probabilities of the presence of a target. The approach is a novel means for incorporating operational knowledge into GMTI processing and admits low-complexity algorithmic implementation via recent advances in Bayesian message passing algorithms. In the second covariance estimator, a regularized shrinkage approach is proposed, whereby prior knowledge is expressed through an elastic net regularization penalty on a minimum expected squared error estimation cost. The regularized shrinkage estimator is shown to coincide with a minimax robust covariance estimator and offers simplicity in modeling and computation that may facilitate use by practitioners. In the third approach, the Bayesian model is augmented to jointly estimate calibration parameters for unknown antenna phases and detect moving targets. The performances of the proposed estimators and detectors are evaluated using the KASSPER I dataset. We conclude that the proposed approaches extend the state-of-the-art to provide reliable detection performance when the training data is limited to a number of range bins less than the rank of the true covariance matrix. Further, when presented no training data, the Bayesian approach is shown to maintain performance using only the data under test. Finally, the purely Bayesian detection approach, when combined with antenna calibration, is observed to provide enhanced resolution, allowing reliable detection of multiple targets within a single range bin not achievable with traditional STAP.
Download or read book Bistatic Space time Adaptive Processing for Ground Moving Target Indication written by Chin-Heng Lim and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design Considerations for an Airborne Ground Moving Target Indicator GMTI Pulse Doppler Radar written by Jean Lavelle Calahan and published by . This book was released on 1981 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Signal Processing for Passive Bistatic Radar written by Mateusz Malanowski and published by Artech House Publishers. This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This cutting-edge resource introduces the basic concepts of passive bistatic radar, such as bistatic geometry, bistatic radar equation and analysis of different illuminating signals. These techniques, although known for almost a century, have not been developed intensively for decades, mainly due to technical limitations, but today, the passive radar concept can be realized in practice, and is of great interest for military and civilian users. This book provides insight into understanding the potential and limitations of passive radar systems, as well as the differences between signal processing in active and passive radar. Each of the signal processing stages typically applied in passive radar is described, including digital beamforming, clutter removal, target detection, localization and tracking. These concepts are illustrated with both simulated and measured data along with examples of passive radar systems.
Download or read book Advances in Bistatic Radar written by Nicholas J. Willis and published by SciTech Publishing. This book was released on 2007-06-30 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive reference updates bistatic and multistatic radar developments since the publication of Nicholas Willis' seminal book Bistatic Radar published in 1991 and revised in 1995. The book is organized into two major sections: Bistatic/ Multistatic Radar Systems and Bistatic Clutter and Signal Processing. New and recently declassified military applications are documented. Civil applications are detailed for the first time, including commercial and scientific systems. Several of the most honored radar engineers of this era provide expertise in each of these applications. Professionals in radar and sonar will find this book a valuable resource
Download or read book Adaptive Radar Detection in the Presence of Textured and Discrete Interference written by Jeong Hwan Bang and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Under a number of practical operating scenarios, traditional moving target indicator (MTI) systems inadequately suppress ground clutter in airborne radar systems. Due to the moving platform, the clutter gains a nonzero relative velocity and spreads the power across Doppler frequencies. This obfuscates slow-moving targets of interest near the "direct current" component of the spectrum. In response, space-time adaptive processing (STAP) techniques have been developed that simultaneously operate in the space and time dimensions for effective clutter cancellation. STAP algorithms commonly operate under the assumption of homogeneous clutter, where the returns are described by complex, white Gaussian distributions. Empirical evidence shows that this assumption is invalid for many radar systems of interest, including high-resolution radar and radars operating at low grazing angles. We are interested in these heterogeneous cases, i.e., cases when the Gaussian model no longer suffices. Hence, the development of reliable STAP algorithms for real systems depends on the accuracy of the heterogeneous clutter models. The clutter of interest in this work includes heterogeneous texture clutter and point clutter. We have developed a cell-based clutter model (CCM) that provides simple, yet faithful means to simulate clutter scenarios for algorithm testing. The scene generated by the CMM can be tuned with two parameters, essentially describing the spikiness of the clutter scene. In one extreme, the texture resembles point clutter, generating strong returns from localized range-azimuth bins. On the other hand, our model can also simulate a flat, homogeneous environment. We prove the importance of model-based STAP techniques, namely knowledge-aided parametric covariance estimation (KAPE), in filtering a gamut of heterogeneous texture scenes. We demonstrate that the efficacy of KAPE does not diminish in the presence of typical spiky clutter. Computational complexities and susceptibility to modeling errors prohibit the use of KAPE in real systems. The computational complexity is a major concern, as the standard KAPE algorithm requires the inversion of an MNxMN matrix for each range bin, where M and N are the number of array elements and the number of pulses of the radar system, respectively. We developed a Gram Schmidt (GS) KAPE method that circumvents the need of a direct inversion and reduces the number of required power estimates. Another unavoidable concern is the performance degradations arising from uncalibrated array errors. This problem is exacerbated in KAPE, as it is a model-based technique; mismatched element amplitudes and phase errors amount to a modeling mismatch. We have developed the power-ridge aligning (PRA) calibration technique, a novel iterative gradient descent algorithm that outperforms current methods. We demonstrate the vast improvements attained using a combination of GS KAPE and PRA over the standard KAPE algorithm under various clutter scenarios in the presence of array errors.
Download or read book The Detection of Moving Targets Among Ground Clutter by Coherent Pulse Methods written by Robert A. McConnell and published by . This book was released on 1943 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Clutter Attenuation Analysis written by Stanley Wilfred Graveline and published by . This book was released on 1966 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of moving target indication (MTI) systems for combat surveillance radars depends to a large extent on the clutter spectrum, which is especially important when the radar attempts to detect slowly moving ground targets. This spectrum has long been assumed to be Gaussian shaped. However, MTI system performance predicted by this assumption was not achieved in practice. This report describes the results of an investigation conducted to determine the performance to be expected from an MTI system. The approach used was to measure the clutter rejection ratios afforded by various high-pass filters. The signal was taken from the boxcar demodulator of an X-band radar observing different clutter targets under varying wind conditions. Clutter rejection ratios of 10 to 40 db were measured. These results were then used to obtain a theoretical expression for the clutter power spectrum. This expression differs from the usual Gaussian assumption. Some credence is given to the results by a direct spectral analysis performed on a clutter signal. Two methods of filtering clutter signals which will result in acceptable MTI performance are suggested in this report. The results of this investigation are significant in that they have led to establishing criteria for a better MTI system design. (Author).
Download or read book Detection of Ground Moving Objects with Synthetic Aperture Radar written by Ishuwa C. Sikaneta and published by . This book was released on 2004 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamentals of Radar Signal Processing written by Mark A. Richards and published by McGraw Hill Professional. This book was released on 2005-07-15 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in DSP (digital signal processing) have radically altered the design and usage of radar systems -- making it essential for both working engineers as well as students to master DSP techniques. This text, which evolved from the author's own teaching, offers a rigorous, in-depth introduction to today's complex radar DSP technologies. Contents: Introduction to Radar Systems * Signal Models * Sampling and Quantization of Pulsed Radar Signals * Radar Waveforms * Pulse Compression Waveforms * Doppler Processing * Detection Fundamentals * Constant False Alarm Rate (CFAR) Detection * Introduction to Synthetic Aperture Imaging