The Detection of Small, Low-lying Surface Targets by Radar

The Detection of Small, Low-lying Surface Targets by Radar PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 506

Get Book Here

Book Description

The Detection of Small, Low-lying Surface Targets by Radar

The Detection of Small, Low-lying Surface Targets by Radar PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 506

Get Book Here

Book Description


Enhanced Detection of Small Targets in Ocean Clutter for High Frequency Surface Wave Radar

Enhanced Detection of Small Targets in Ocean Clutter for High Frequency Surface Wave Radar PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
The small target detection in High Frequency Surface Wave Radar is limited by the presence of various clutter and interference. Several novel signal processing techniques are developed to improve the system detection performance. As an external interference due to local lightning, impulsive noise increases the broadband noise level and then precludes the targets from detection. A new excision approach is proposed with modified linear predictions as the reconstruction solution. The system performance is further improved by de-noising the estimated covariance matrix through signal property mapping method. The existence of non-stationary sea clutter and ionospheric clutter can result in excessive false alarm rate through the high sidelobe level in adaptive beamforming. The optimum threshold discrete quadratic inequality constraints method is proposed to guarantee the sidelobe-controlling problem consistently feasible and optimal. This constrained optimization problem can be formulated into a second order cone problem with efficient mathematical solution. Both simulation and experimental results validate the improved performance and feasibility of our method. Based on the special noise characteristics of High Frequency radar, an adaptive switching Constant False Alarm Rate detector is proposed for targets detection in the beamformed range-Doppler map. The switching rule and adaptive footprint are applied to provide the optimum background noise estimation. For this new method about 14% probability of detection improvement has been verified by experimental data, and meanwhile the false alarm rate is reduced significantly compared to the original CFAR. The conventional Doppler processing has difficulty to recognize a target if its frequency is close to a Bragg line. One detector is proposed to solve this co-located co-channel resolvability problem under the assumption that target/clutter have different phase modulation. Moreover with the pre-whitening processing, the Rever.

Radar Target Detection

Radar Target Detection PDF Author: Daniel Meyers
Publisher: Elsevier
ISBN: 0323147534
Category : Technology & Engineering
Languages : en
Pages : 513

Get Book Here

Book Description
Radar Target Detection: Handbook of Theory and Practice covers a set of graphical solutions to the detection problem, designated as Meyer Plots, for radar systems design. A radar system's major purpose is the detection and location of an object by means of a return signal, which could be either a reflection or a beacon. This book is composed of four chapters. Chapter 1 presents the basic radar range equation, which is the basic relationship which permits the calculation of echo signal strength from measurable or known parameters of the radar transmitter, antenna, propagation path, and target. Chapter 2 provides examples for determining statistical signal detection using Meyer Plots, particularly for determining detection probability and integration loss and efficiency. Chapter 3 describes the application of target models to determination of detection probability. Chapter 4 examines how Meyer Plots can be used to solve problems involving most any target model.

Test and Evaluation of the AN/APS-145 Radar Surface Detection and Discrimination Capability Between Small Radar Cross Section Surface Targets and Free Floating Objects

Test and Evaluation of the AN/APS-145 Radar Surface Detection and Discrimination Capability Between Small Radar Cross Section Surface Targets and Free Floating Objects PDF Author: Nigel James Sutton
Publisher:
ISBN:
Category : Radar
Languages : en
Pages : 268

Get Book Here

Book Description


Advances in Radar Techniques

Advances in Radar Techniques PDF Author: John Clarke
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 538

Get Book Here

Book Description


High resolution methods for small target detection and estimation in high frequency radar

High resolution methods for small target detection and estimation in high frequency radar PDF Author: Jian Wang (Ph. D.)
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
The detection and tracking of small slow moving targets by High Frequency Surface Wave radar are limited by the presence of a dominate sea clutter spectrum. The ocean surface behaves as a distributed source in contrast to targets that are point sources. It is shown that by mapping data to eigenspaces, the sea clutter level decreases due to its nondeterministic behaviour while point targets' levels remain unchanged. The high resolution (subspace-based or eigenspace) methods and frequency tracking method for slowly time varying frequencies are evaluated to suppress this sea clutter to enhance detection of weak signals. Experimental results verify the advantage of subspace-based methods over the traditional processing techniques. Conventional subspace methods can be utilized to enhance the detection, but they deteriorate dramatically in the presence of correlated sea clutter. In our thesis some adaptive sea clutter pre-filtering schemes are introduced which improve the threshold and accuracy of subsequent subspace methods. Both simulated and real ship targets are used to verify the effectiveness of our proposed method. Furthermore, we propose another novel subspace algorithm to estimate the directions of arrival of superimposed cisoidal radar echoes from far-field targets in the radar pulse domain. The improvement provided by this algorithm is based on the use of a state space model that more accurately represents the received Doppler radar array signal prior to spatial processing such as MUSIC. A 2-d (spatial and temporal) pre-filtering matrix is structured and applied to the received array signal, which is finally combined with the high-resolution (MUSIC) method for DOA estimation. Lower resolution threshold and estimation variance are achieved by this algorithm compared to conventional beam-space MUSIC and sensor-space MUSIC. A simplified theoretical resolution threshold is derived, and both the theory and simulations verify the effectiveness of our proposed algorithm. Results from an experiment using a simulated target superimposed on real HF radar sea clutter also confirm the algorithm.

New American Practical Navigator

New American Practical Navigator PDF Author:
Publisher:
ISBN:
Category : Nautical astronomy
Languages : en
Pages : 1412

Get Book Here

Book Description


Flash Flood Forecasting Over Complex Terrain

Flash Flood Forecasting Over Complex Terrain PDF Author: National Research Council
Publisher: National Academies Press
ISBN: 0309093163
Category : Science
Languages : en
Pages : 206

Get Book Here

Book Description
The nation's network of more than 130 Next Generation Radars (NEXRADs) is used to detect wind and precipitation to help National Weather Service forecasters monitor and predict flash floods and other storms. This book assesses the performance of the Sulphur Mountain NEXRAD in Southern California, which has been scrutinized for its ability to detect precipitation in the atmosphere below 6000 feet. The book finds that the Sulphur Mountain NEXRAD provides crucial coverage of the lower atmosphere and is appropriately situated to assist the Los Angeles-Oxnard National Weather Service Forecast Office in successfully forecasting and warning of flash floods. The book concludes that, in general, NEXRAD technology is effective in mountainous terrain but can be improved.

Detection And Identification Of Visually Obscured Targets

Detection And Identification Of Visually Obscured Targets PDF Author: Carl E. Baum
Publisher: Routledge
ISBN: 1351455664
Category : Technology & Engineering
Languages : en
Pages : 460

Get Book Here

Book Description
Beginning with a review of the current need for identification of buried and surface unexplored ordnance such as mines, shells, bombs, this book then explains existing techniques for electromagnetic detection of such targets. A detailed treatment of target signatures (natural frequencies and related parameters) for identification and discrimination of false alarms is also given.

Use of a navigation radar for detection of small surface targets and rapid environmental assessment

Use of a navigation radar for detection of small surface targets and rapid environmental assessment PDF Author: J.C.M. Kleijweg
Publisher:
ISBN:
Category :
Languages : nl
Pages : 52

Get Book Here

Book Description