Matlab sea clutter. MIT Lincoln Laboratory Radar Course_19.

Matlab sea clutter Assume that the patch is 1000 meters away from the radar system and the azimuth and elevation beamwidths are 1 degree and 3 degrees, respectively. 12. This tutorial describes the various ways in which clutter is modeled and introduces some of the ways in which models are used in radar design. This example will introduce a sea clutter simulation for a maritime surveillance radar system. 4 days ago · Now we have published the data loading code, which is a Python re-implementation according to the Matlab version on IPIX website. Aug 12, 2022 · The sea clutter model based on the physical sea surface can simulate radar echo at different times and positions and is more suitable for describing dynamic sea clutter than the traditional models based on statistical significance. Marine radar is The network completely removes the sea clutter below a certain threshold of returned power while retaining the target signals with only a small dilation effect due to the size of the convolution filters used. doi: May 10, 2017 · Learn more about clutter, sea clutter, k distribution, log distribution, statistics, signal processing Phased Array System Toolbox So far I am reading papers from the internet. @misc{zhou2020smallfloating, title={Small-floating Target Detection in Sea Clutter via Visual Feature Classifying in the Time-Doppler Spectra}, author={Yi Zhou and Yin Cui and Xiaoke Xu and Jidong Suo and Dec 7, 2019 · In this section, we briefly introduce the K-distributed sea clutter model, CFAR detection, and shape parameter estimation, which serve as the precursors of our proposal. Determine the γ value for a wooded area, and then simulate the clutter return from that area. Riemannian mean is an average estimation which obtains the local minimum of the objective function defined by variance. You can use the SeaSurface object to determine sea heights in a scenario and surface reflectivity, test for occlusion along the line-of-sight between two points in the scenario and give surface height at a point. The first data sequence from sea and land is used Clutter Modeling Surface Clutter Overview. local grazing angle Simulate sea clutter for a maritime surveillance radar system and calculate the clutter-to-noise ratio (CNR). As an example, the k th clutter value after sorting is used as the power estimate in the order statistic CFAR (OS-CFAR) detector [21], it performs relatively robustly under multiple target interference, however, once the number of Mar 1, 2019 · 通过上述代码实现，可以在MATLAB中进行K分布雷达杂波建模与仿真，并得到K分布随机变量序列和K分布雷达杂波序列。实际应用中，还需要根据具体情况进行参数的调整和优化，以达到最佳的雷达性能和目标探测效果。K分布也称作Nakagami-k分布 hgtsd — Standard deviation of the surface height for the specified sea state number. Currently, the approaches employed in X-band marine radar target detection can be categorized into two groups [2]: constant false alarm rate (CFAR) for detecting targets and track before detection (TBD) for tracking targets. The very commonly used and well established base band equivalent model for radar clutter is a complex Gaussian process, which implies that Chi-Square for power, or equivalently Rayleigh hgtsd — Standard deviation of the surface height for the specified sea state number. rar_clutter-simulation_matlab 海杂波_matlab海"提供了关于海杂波仿真的相关资料，主要涉及海杂波的建模以及MATLAB实现。下面将详细介绍这个主题中的关键知识点。 一、海杂波的 Apr 14, 2022 · Marine surveillance radar is widely used in marine monitoring for its ability of observing sea surface all-time and all-weather. To guarantee an adequate radar performance in the presence of sea clutter, the family of constant false-alarm rate (CFAR) detectors has Finally, enable clutter generation for the radar by calling the clutterGenerator method on the scenario. However, due to the lack of real data, many of these only span a limited parameter space, either covering low gazing angles (typically less than 10°) or medium grazing angles (greater than 15°). Set the range limit to 20 km to encompass the entire beam. The aim of marine radar is to minimise the clutter of sea, rain and snow, suppress the same frequency interference and noise, and keep the target information of vessels, islands, buoys and lighthouses etc. This example will introduce a sea clutter simulation for a maritime surveillance radar system. In this paper we propose a novel convolutional neural network based dual-activated clutter suppression algorithm, to solve the problem caused by low signal-to-clutter ratios in actual situations on the sea surface. changes with time, while for ground clutter it stays the same. Navya and R. Since R2021a; Open Live Script; Modeling Target Position Errors Due to Refraction You clicked a link that corresponds to this MATLAB command: Run the command by entering it in the MATLAB Command Window. However, the radar target detection performance is seriously affected by the existence of sea clutter. The γ values for the terrain types "Sea State 3", "Sea State 5", "Woods" Run the command by entering it in the MATLAB Command Window. 1109/LGRS. You will then generate IQ returns from the sea surface and investigate the statistics and Abstract: Multi-band Doppler spectrum of radar clutter at there-dimensional sea surface is calculated in this paper, the Elfouhaily sea spectrum with a direction function is applied to achieving the scattering fields is a classic PO method. Study on sea clutter suppression methods based on a realistic radar dataset[J]. In this letter, to deal with the limitation of the traditional generalized-K (GK) distribution in highly heterogeneous clutter scene, a modified GK (MGK) distribution is Feb 26, 2018 · Sea Clutter Echoes, K-Distribute Model, ZMNL, SIRP 雷达海杂波K分布序列模型仿真ZMNL和SIRP方 法比较分析 叶灵伟，夏 栋，郭维波 海军航空大学青岛校区，山东 青岛 收稿日期：2018年2月7日；录用日期：2018年2月19日；发布日期：2018年2月26日 May 30, 2019 · Carrying out sea clutter measurement experiments and obtaining measurement data under the influence of different parameters is an important prerequisite for supporting this research. 0 km away from the radar system. The physical mechanism of sea clutter is complex with an abundance of influencing factors, and the non-Gaussian as well as non-stationarity behavior is significant. When trying to detect or track targets moving on or above the surface, you must be able to distinguish between clutter and the targets of interest. The definition of ideal CFAR May 10, 2017 · Learn more about clutter, sea clutter, k distribution, log distribution, statistics, signal processing Phased Array System Toolbox So far I am reading papers from the internet. The surface σ 0 value for sea clutter reflectivity is computed based on the NRL Sea Clutter Model by Gregers-Hansen and Mittal. Conventional clutter rejection methods, when the target signal and first-order sea clutter are mixed in the Doppler spectrum, tend to eliminate both the target signal and clutter without distinction. First, we multiply the Abstract: Sea clutter magnitude distribution exhibits important guiding significance for the design of marine target detection algorithms and the selection of the constant false alarm rate (CFAR) detection threshold. To calculate the mean matrix, the Riemannian mean based on the RD metric is introduced. Clutter detections will be generated with a monostatic radarDataGenerator, and clutter return signals will be generated Jan 31, 2024 · Some existing sea clutter models are given in reference [5]. The current implementation supports sea clutter in any of five sea states with configurable polarization, grazing angle, and This example shows how to generate monostatic surface clutter signals and detections in a radar scenario. 1 Excerpt; Save. Thus, research into sea clutter property cognition is complicated and has to be systematic. It can be seen from the greyscale of the image that there is a In modern radar systems, the Generalized compound distribution model is more suitable for describing the amplitude distribution characteristics of radar sea clutter. This example first discusses the physical properties associated with sea states. However, for close to ten millions of clutter May 31, 2024 · Finally, we generate random series A using corresponding random data generator and then add instantaneous phase 휃 into A, i. In order to capture more of the surface return, disable this by setting UseBeam to false, and instead use a RingClutterRegion with an azimuth coverage 16 times that of the beam to encompass some Nov 15, 2021 · In this paper, an approach for radar clutter, especially sea and land clutter classification, is considered under the following conditions: the average amplitude levels of the clutter are close to each other, and the distributions of the clutter are unknown. We will propose a novel sea clutter suppression and small target detection method here. This paper explores the performance of cell-averaging CFAR (CA-CFAR) detectors in sea clutter, using the compound K-distribution clutter model. The clutter model is based on the Simkins Unified Clutter Model[1]. This is followed by a description of the CA-CFAR configuration being investigated and a definition of CFAR loss. Target detection is Aug 28, 2019 · Sea clutter is composed of echo vectors of lots of scatters within the range bin of sea surface and is affected by various factors such as the operating frequency of the radar, the resolution of the radar, the rubbing angle, and so on. Ship signature : • Depending on size, polarization, line of sight Detection capability Absolute measurements: calibration * Ward K. Also assume that the grazing angle is 20 degrees, the pulse width is 10 microseconds, and the radar is operated at a Jul 13, 2021 · Detection Techniques in Sea Clutter Background R. As a result, the overestimated threshold leads to a degradation in detection probability. xPatch x-coordinate of the surface patch (meters This paper presents a sea clutter suppression (SCS) method for single-channel maritime radar based on a deep Convolutional Neural Network (SCS-CNN), which consists of an encoder and a decoder. 8 Appendix Evaluation of J 1. Boston: Artech House, 2001. rar_clutter-simulation_matlab 海杂波_matlab海"提供了关于海杂波仿真的相关资料，主要涉及海杂波的建模以及MATLAB实现。下面将详细介绍这个主题中的关键知识点。 Nov 28, 2021 · Sea clutter influences the detection of targets in extreme sea conditions, which in turn increases the probability of false alarms. 2019 image that there is a strong sea clutter in the near area of Jan 14, 2021 · additional information such as sea clutter, rain and snow clutter, active interference and system noise [1]. g. Next, it discusses the reflectivity of sea surfaces, investigating the effect of sea Sea clutter is one of the main limiting factors influencing the target detection performance of nautical radars. Through a comparison of simulated sea clutter and measured sea clutter data via histogram, the validity of the proposed method is proved. Frequency or Grazing angle. Sie haben auf einen Link geklickt, der diesem MATLAB-Befehl entspricht: Führen Sie den Befehl durch Eingabe in das MATLAB-Befehlsfenster aus. The resolution for the custom case is calculated as Resolution = surface length. Space-time adaptive processing (STAP) is a powerful method to suppress the clutter but the practical radar system parameters and the training sample starved scenario degrade the performance of STAP. Run the command by entering it in the MATLAB Command Window. Fig. This clutter gets also a Doppler- speed by the wind. Jan 14, 2021 · TC sea clutter is more concentrated in some particular areas and the energy of small targets is distributed among the entire wave number domain. , y = A e j 휃, to obtain simulated sea clutter series. Set this to be 1/5th of the range resolution to get multiple clutter patches per range gate. In multiple-target scenarios, the target masking effect reduces the detection performance of CFAR detectors evidently. However, the model does not always agree with the tabulated measured sea clutter data, especially at low sea states. Using observations of recorded Doppler spectra, a simple method is proposed for characterizing the temporal variations of the Doppler spectrum observed in a single-range cell. theaterPlot is used to visualize the scenario surface and Add two clutter regions to the scenario. 1. 024 km. The object describes the size, surface reflectivity, motion, and wind speed of the surface. In this article, a weighted biased soft-margin support vector machine (WBSM-SVM) algorithm is Now, use the scenario clutterGenerator method to construct a clutter generator and enable clutter generation for your radar. The amplitude of noise, rain and snow clutter and sea clutter at low-resolution situation varies greatly in fluctuation Jul 15, 2022 · 在雷达系统中，海杂波是影响目标检测和识别的重要因素。这个压缩包"sea-clutter_simulation. Matlab / Python NRL model of bistatic sea surface radar reflectivity for hot clutter modeling. Reproducing the temporal and spatial correlations of real data simultaneously is always a problem in the Simulate sea clutter for a maritime surveillance radar system and calculate the clutter-to-noise ratio (CNR). These include the mean backscatter power, amplitude statistics, spatial and long-time temporal correlation, and the Doppler spectrum. The probability of detection is shown to be sensitive to the degree of estimation accuracy of clutter levels. The running time Sep 16, 2020 · Using SAR images to detect ships from sea clutter[J]. Clutter detections will be generated with a monostatic radarDataGenerator, and clutter return signals will be generated  · Matlab NRL model of bistatic sea surface radar reflectivity for hot clutter modeling. Using sea clutter data at low grazing angles observed by a The network completely removes the sea clutter below a certain threshold of returned power while retaining the target signals with only a small dilation effect due to the size of the convolution filters used. doi: 10. Add a sea surface object to define the physical properties of the scenario surface. This may Calculate the radar cross section of a clutter patch and estimate the clutter-to-noise ratio at the receiver. IEEE Geoscience and Remote Sensing Letters, 2008, 5(2): 194–198. Jun 3, 2013 · 这个压缩包"sea-clutter_simulation. Second, the decoder is used to selectively Jul 26, 2019 · Specifically, sea state is quantified by a term known as significant wave height or the average height of the highest one third of the waves in a wave train. 1049/joe. Add an Elfouhaily spectrum to the sea surface. A comparison of the results obtained using two machine learning techniques for the Jun 26, 2009 · Radar detection of targets in sea clutter modelled by compound K-distribution is examined from a statistical detection viewpoint by Monte Carlo simulations. The clutter is assumed to be log-normal, The radar system is a fixed, offshore platform. 2 introduces the characteristics of clutter as observed by radars and the methods used to The most fundamental characteristic of sea clutter, Appendix B lists the MATLAB code that can be used to determine the sea clutter reflectivity given the sea state, radar frequency, grazing angles and polarization. When trying to detect or track targets moving on or above the surface, you must be able to This example shows how to generate monostatic surface clutter signals and detections in a radar scenario. 2. , 2019, 11 Jun 3, 2013 · 文件名称: Sea-clutter-simulation下载 收藏√ [5 4 3 2 1]开发工具: Visual C++文件大小: 18 KB上传时间: 2013-06-03下载次数: 69提 供 者: 黄颖详细说明：海杂波仿真程序，包括单基地雷达和双基地雷达的一阶、二阶海杂波仿真-Sea clutter simulation Oct 22, 2021 · In this paper, the datasets were collected on the East China Sea by a civil navigation radar system. So the reflectivity is generally termed as apparent reflectivity Add a sea surface object to define the physical properties of the scenario surface. A widely used sea clutter model proposed by Horst et al. The emphasis is on understanding the characteristics of radar sea clutter as observed with different radars, viewing geometries and environmental conditions. Range migration of the target was visible due to the high resolution and slow update rate of the radar. In this paper, the novel use of machine learning techniques is explored to address this familiar problem. Run the command by entering it in the MATLAB This example will introduce a sea clutter simulation for a maritime surveillance radar system. The current emphasis is on sea clutter; as a result Apr 10, 2007 · The method of spherically invariant random process (SIRP) allows independent control of the margin probability density function (PDF) and the autocorrelation of clutter, which overcomes the infection of zero memory nonlinear (ZMNL) on autocorrelation. Sea clutter often exhibits various properties of distribution form and spatial-temporal correlation in the Jan 15, 2024 · DSTO conducted a Sea Clutter Trial in 2004 (SCT04) in the Southern Ocean at a location approximately 100 km south of Port Lincoln in South Australia. In this paper, we proposes a sea clutter suppression method based on machine learning that contains two pairs of generative adversarial networks (GANs), in which one GAN is used to learn the mapping The non-homogeneous clutter environment is the biggest challenge for sea clutter suppression in the background of high frequency hybrid sky-surface wave radar (HFSSWR). In this work, the performances of logt-CFAR, zlog(z)-CFAR and Bayesian-CFAR detectors are investigated using both simulated and real data. Reflectivity, defined as σ0, is the most fundamental characteristic of Sea clutter which is used in evaluating radar performance. The remaining high-power clutter near the center of the images could be removed by a spatially-aware layer, such as a fully-connected May 15, 2017 · This letter presents a novel signal processing method for HF surface wave radar that offers a solution to suppress significant sea clutter interference. Therefore, the speed up provided by GPU over the MATLAB interpreter starts to decrease. Oct 1, 2012 · The sea clutter phenomenon is investigated from a different perspective by using the finite element domain decomposition (FEDD) method, which is a full -wave numerical method based on the Sep 1, 2012 · Abstract Retrieving atmospheric refractivity profiles from the sea surface backscattered radar clutter is known as the refractivity-from-clutter (RFC) technique. Sea clutter is simulated using constant gamma clutter model for sea state 5 condition using polyphaser system object in MATLAB with sea clutter level of-30 dB. Surface clutter refers to reflections of a radar signal from land, sea, or the land-sea interface. May 25, 2017 · The work in this paper is devoted to developing a statistical model of the filter in nonhomogeneous sea clutter to achieve constant false alarm rate (CFAR) detection based on the model. Semantic Scholar extracted view of "Sea Clutter Simulation" by Titus Oyedokun. beta0 is 1. The data are measured with the McMaster IPIX Radar, a fully coherent X-band radar, with advanced features such as dual transmit/receive polarization, frequency agility, and stare Feb 24, 2023 · Since the sea clutter intensity PDF meets the log-normal distribution, the log-intensity value \(ln(X)\) By CPU time, we merely intend to estimate and compare the consumption time of all detectors via the ”SPSVERBc1” MATLAB built-in function, i. October 2019; The Journal of Engineering 2019(2A) DOI:10. In this article, we propose a new sea clutter suppression method based on machine learning approach. In this article, we propose a novel 3-D target detection algorithm that effectively identifies vessel targets in sea clutter using multidimensional fusion features. Maurice W. Correlated K-distribution is often offered as a non-Gaussian distribution model which can well describe the characteristics of radar sea clutter. Researches on sea clutter are of great significance for the detection of targets on the sea in complex clutter background. You will learn how to: Model a land surface with digital Jan 27, 2012 · In this paper we describe an extension to the MATLAB Phased Array Toolkit that adds a configurable clutter object to model clutter signals returned along a specified signal path. 1，运行平台为Window XP。杂波模拟也就等于模拟同时具有特定的概率密度(PDF)和功率谱密度(PSD)的随机过程。本设计首先用M文件S函数编写了十二种常用的杂波模块（包括Rayleigh分布、LogNormal分布、Weibull分布、K分布的Gaussian谱、Cauchy谱、AllPole谱杂 Dec 21, 2023 · • Sea state • Polarization state • Frequency band . Simulate sea clutter for a maritime surveillance radar system and calculate the clutter-to-noise ratio (CNR). Journal of Radars, 2019, 8(3): 281–302. No Matlab toolboxes are used. The simulation model of coherent correlation K-distributed clutter using SIRP, with the modeling of coherent This book provides an updated and comprehensive review of the latest research into radar sea clutter and detection methods for targets in sea clutter. Webbrowser Feb 12, 2024 · In complex environments, the clutter statistical characteristics of synthetic aperture radar (SAR) are inconstant, and the constant detection performance of a false alarm rate (CFAR) detector based on a clutter statistical model is also hard to achieve. Accurately and efficiently simulating sea clutter has important practical significance for radar signal processing and sea surface target detection. This paper Radar propagation, land and sea clutter, atmospheric models, attenuation due to gas, fog, rain and snow . Next, it discusses the reflectivity of sea surfaces, investigating the effect of sea The constantGammaClutter System object™ simulates constant gamma clutter reflected from homogeneous terrain for a monostatic radar transmitting a narrowband signal into free space. In the past few decades, scientists have been pouring enormous endeavours into the electromagnetic (EM) scattering studies of the rough sea surface, which can play an important role in the synthetic aperture radar (SAR) imaging, oceanic environment monitoring, and target detection [-]. (MAtlab Test Environment for CFAR detectors) para la prueba de detectores CFAR y la modelacion de clutter y blancos de radar. md at main · scivision/nrl-radar-sea-clutter Jan 23, 2024 · data base of sea clutter reflectivity available to the radar systems engineer. These including the mean backscatter, amplitude statistics, short-term temporal correlation (including that represented by the Doppler spectra) and any spatial or longer-term temporal Omnidirectional wave spectrum, specified as an M-by-N matrix. The 3 dB beamwidth of the beam is used for clutter generation by default. Next, it discusses the reflectivity of sea surfaces, investigating the effect of sea In this example you simulated a stationary coastal surveillance radar with sea surface clutter. Therefore, it is critical to construct a realistic breaking wave model and study its electromagnetic (EM) scattering characteristics. You will first generate a moving sea surface at sea state 4 using the Elfouhaily spectrum model. Dual activation has two steps. beta0 — Slope of the sea type. 5 days ago · Environment and Clutter. The proposed approach divides the dataset into two parts. Small target echoes are weak in energy, and can be submerged by sea clutter and sea spikes, which are caused by overturning waves and breaking waves. Use a radar frequency of 1 GHz, a 100 meter range resolution, a 5 kHz Add a sea surface object to define the physical properties of the scenario surface. NRL Radar sea clutter model (2012) by Mital & Gregers-Hansen - nrl-radar-sea-clutter/README. IEEE Transactions on Aerospace and Electronic Systems, 2010, 46(3): 1502–1513. The remaining high-power clutter near the center of the images could be removed by a spatially-aware layer, such as a fully-connected Create a square sea surface assuming a moderate sea state with a wind speed of about 12 knots (6. Explore some environmental factors that are beyond a radar system designer's  · A Matlab program that generates plots vs. In developing this new empirical sea clutter model, no attempt was made to explicitly include any preassumed behavior as a . The radar detection of small maritime targets requires special attention to the suppression of sea clutter returns that, in certain circumstances, may be difficult to discriminate from target returns. Use Nov 22, 2017 · 7 7/157 Normalized RCS σ0 R Radar pulse Elevation R Azimuth h ψ Clutter patch antenna footprint φgr ρ θel θaz R θaz ρsec φgr The normalized clutter reflectivity, σ0, is defined as the total RCS, σ, of the scatterers in the illuminated patch, normalized by the area, A c, of the patch and it is measured in units of dBm 2/m 2. Start by creating a radarDataGenerator. An extended cuboid target was used to emulate a ship with partial occlusion by the sea surface. For example, a ground moving target indicator (GMTI Jul 11, 2019 · Based on MATLAB, the sea-echo simulation and analysis system is designed, and the tool software is MATLAB 2016b. By utilizing the test RD spectrum and clutter dictionary D, the sparse reconstruction algorithm can effectively extract sea clutter components in the RD spectrum, reconstruct sea clutter and suppress outliers. Sea-Clutter can be seen Add a sea surface object to define the physical properties of the scenario surface. Apr 22, 2020 · The reconstruction of sea clutter plays an important role in target detection and recognition in a maritime environment. Oct 8, 2012 · This paper describes a new technique for modeling and simulating the coherent returns from radar sea clutter, based on the compound K-distribution model for clutter amplitude statistics. Larger spectrum width and shift have been seen in larger wind speed Aug 5, 2021 · 实现了杂波信号的建模与仿真。系统的开发平台为MATLAB 7. Model and analyze radar propagation effects of land and sea clutter; atmospheric attenuation due to gas, fog, rain and snow; and lens effects losses. Use the occlusion object function to determine if the path from point 1 to point 2 is occluded. The performance evaluations are quantified by Jun 1, 2024 · Detecting weak targets efficiently in the presence of complicated sea clutter is always an issue for maritime radar [1]. 9k次，点赞3次，收藏34次。【代码】读取 IPIX雷达 / 海杂波 数据。_ipix数据集 关于IPIX雷达数据读取（cdf文件读取）和处理的相关程序，适用于matlab2010及更新的matlab版本，压缩文件里面有较详细程 The radar system is a fixed, offshore platform. 2008. This severely affects the radar target detection performance. 32 Add two clutter regions to the scenario. Start by creating a radar scenario; Aug 5, 2022 · Keywords: Radar, modelling, sea clutter, STAP ABSTRACT A two component clutter model is proposed to aid in the simulation of the spatio-temporal characteristics of radar sea clutter backscatter returns collected from moving airborne platforms. You will then generate IQ returns from the sea surface and investigate the statistics and Clutter Modeling Surface Clutter Overview. In this letter, a novel sea clutter suppression generative adversarial Marine surveillance radar can monitor the marine environment in all-weather conditions, but the presence of sea clutter will seriously affect its target detection performance. Therefore, in practice, Sea-clutter is very difficult to control without some loss in detection. Devaraju Abstract Sea clutter is an unwanted return or echo signal which exhibits non-linearity and disarray and is random in nature. /size(CustomSpectrum), where surface length is the sea surface physical Oct 3, 2024 · Shipborne high-frequency surface wave radar (HFSWR) systems face the challenge of sea clutter spreading, which obscures vessel echoes and makes detection difficult. The Resolution property defines the nominal spacing of clutter patches. The Abstract. Sep 22, 2022 · 文章浏览阅读3. Regarding the latter, a common modeling approach is to use the mean Doppler characteristics (width and center Nov 15, 2023 · The detection of small targets within the background of sea clutter is a significant challenge faced in radar signal processing. Dec 16, 2024 · Sea-clutter are disturbing radar-echoes of sea wave crests. However, when applying the physical surface model to shore-based radar, the effects of wave nonlinearity, breaking wave, shadow, and Jan 1, 2015 · This work forms part of the NATO SET-185 collaboration on radar sea clutter. Clutter detections will be generated with a monostatic radarDataGenerator, and clutter return signals will be generated with a radarTransceiver, using both homogenous surfaces and real terrain data from a DTED file. However, the sea clutter suppression ability of current algorithms is limited with poor generalization under complex marine environment. Highlights. Bibtex. From Dan Codiga. Use the surfaceReflectivitySea function to create a GIT model with a sea state 3. Each range cell to be detected is regarded Dec 18, 2020 · ALL-WEATHER SENSE AND AVOID (SAA) RADAR CLUTTER MODELING AND CONTROL A THESIS SUBMITTED TO THE GRADUATE FACULTY in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE By an airborne system model based on MATLAB toolboxes, NASA’s airborne radar flight test data, and NEXRAD radar data. May 17, 2021 · Anti-ship missiles are a primary threat to naval targets because sea-skimming tactics enable the missile to approach the vessel while being obscured by sea clutter. This paper proposes a Clutter Modeling Surface Clutter Overview. An adaptive and fast CFAR algorithm based on automatic Mar 17, 2017 · A collaborative effort to organize Matlab tools for the Oceanographic Community. The first section provides a brief introduction to the compound K-distribution model. First, filter the TC sea clutter in image spectrum field and then use the 2D CFAR technique to detect targets 6 days ago · Environment and Clutter. jLab: A Matlab toolbox for big data analysis, signal processing, Apr 21, 2021 · 海杂波模拟与循环对消法实现杂波抑制的matlab源程序源码，包含不不同信噪比下的目标回波和最小二乘实现的滤波器完成杂波抑制 可直接使用。 -Sea clutter simulation and cycle cancellation method for clutter suppression Matlab source code, including Oct 26, 2017 · There are a number of empirical models for the sea clutter mean backscatter and the K distribution shape. Flat and curved Earth models with and without ITU atmospheric models. 11. Next, it discusses the reflectivity of sea surfaces, investigating the Jan 19, 2023 · Sea clutter has been a long-standing issue in old and modern radars. We first employ a cyclic structure Oct 1, 2019 · Simulation and analysis system of sea echo based on MATLAB. First, the encoder is used to extract depth features of the original Range-Doppler spectrum obtained from sub-aperture echoes. Under this context, the K-distribution has emerged as a promising clutter model to accurately mimic sea signal variations in a large variety of radar systems. , sea spikes, may bring in low signal-to-clutter ratio (SCR) and cause great interference to radar marine target detection. The Aug 7, 2020 · The problem of strong sea clutter, e. Assume the radar system uses a single cosine pattern antenna element and has an operating frequency of 300 MHz. Characterize clutter using sea state and permittivity in addition to land surface with vegetation type and permittivity. 6 and 7 show the PPI display of sea echo. Clutter Modeling Surface Clutter Overview. 7 is the image of 60th frame. The algorithm consists of two stages: 3-D Jun 11, 2015 · For the accurate representation of the sea clutter observed at medium and high grazing angles, the authors modelled in MATLAB the Weibull-Weibull and K-K mixed distributions, which are frequently Sep 24, 2020 · 1 Introduction. This paper introduces the method of constructing the sea clutter, sea clutter amplitude distribution and power spectrum distribution characteristics of the model, using the ZMNL method of the K distribution sea clutter simulation, simulation results show that, it greatly reduces the amount of computation based on ZMNL method of K Distribution Sea Clutter Modeling and Simulation, Jul 24, 2018 · At low grazing angles, sharp sea clutter peaks, known as “sea spikes”, begin to appear • These sea spikes can cause excessive false detections Figure by MIT OCW. Section 2. The network communication interface is designed to realise the real-time communication of radar echo data. When trying to detect or track targets moving on or above the surface, you must be able to Generate clutter from a surface having two clutter regions. To address this problem, Jun 1, 2024 · In contrast to the mean level CFAR detector, the auto-filter CFAR detector uses a different class of clutter power estimate methods. UTide: Expands and integrates the t_tide (Pawlowicz et al 2002), r_t_tide (Leffler and Jay 2009), IOS Tidal Package (Foreman et al 2009) approaches into a common framework. K-Distributed Sea Clutter Model In the K-distributed model, sea clutter signal X is usually considered the product of two independent components, given by: X = p XG XR Jan 13, 2025 · Matlab, GNU Octave, or Python on any operating system. The detection performance of Cell Averaging Constant False Alarm Rate (CA-CFAR) is compared with the performance of fixed threshold detection. May 7, 2022 · The ability to detect small targets in sea clutter is still an ongoing challenge, even for modern radar systems. The left column of Figure 1 illustrates the amplitudes of sea clutter without Jan 10, 2019 · 在复杂海洋环境条件下，海上目标探测性能受海杂波的影响很大。海杂波影响因素众多，机理复杂，特征描述和抑制难度大，需要开展长期、系统、持续、深入研究。开展海杂波测量试验并获取不同参数影响下的测量数据，是有效支撑该研究的重要前提。 Oct 25, 2020 · Current methods for radar target detection usually work on the basis of high signal-to-clutter ratios. Figure 1 illustrates the intensities of sea clutter echoes with respect to four different sea states, where the x-axis represents the radial distance, and the y-axis indicates the echo amplitude. e. Because the relationship between refractivity and radar sea clutter is clearly nonlinear and ill posed, it is difficult to get analytical solutions according to current theories. The composite surface theory (CST) [, ], which can make a For radar modeling and simulation of sea clutter, there are a number of key characteristics used to describe the observed features. 12000/JR19006 [3] LV Mingjie and ZHOU Chen. (1978) (GIT model) has found widespread acceptance in the radar community. The simulation approach is seen to reproduce key characteristic of the real data and supports the Aug 22, 2019 · Figs. Unfortunately I am not that good in signal and statistics topics. Start by creating a radar scenario; Create a square sea surface assuming a moderate sea state with a wind speed of about 12 knots (6. , the time between the start and the completion of a given detector’s routine. M and N dictate the inverse fast Fourier transfer (IFFT) length when returning the elevation data of the sea surface in the x and y dimensions, respectively. ppt ODonnell (1) 6-19-02 Outline • Motivation • Ground Clutter • Sea Clutter • Rain • Chaff • Apr 24, 2019 · This website has been developed to make a large number of high quality and well documented sea clutter data sets available to the radar research community. . Time Series Tools . 24 km), and a length of 1. Previous works treat this problem as a May 24, 2022 · Overview and prospects of radar sea clutter measurement experiments[J]. 915593 [15] GAO Gui, LIU Li, ZHAO Lingjun, et al. MIT Lincoln Laboratory Radar Course_19. 4 times the root mean square (RMS) surface slope. Use the clutterGenerator object function to construct a clutter generator and enable clutter generation for the radar. So simulation is an obvious prerequisite if the radar is set to operate in hostile scenarios. 17 m/s), a fetch of 120 nmi (222. Dec 5, 2019 · For K-distributed sea clutter, a constant false alarm rate (CFAR) is crucial as a desired property for automatic target detection in an unknown and non-stationary background. Vous avez cliqué sur un lien qui correspond à cette commande MATLAB : Sep 4, 2024 · In the complex clutter background, the clutter center frequency is not fixed, and the spectral width is wide, which leads to the performance degradation of the traditional adaptive clutter suppression method. Therefore, an adaptive clutter intelligent suppression method based on deep reinforcement learning (DRL) is proposed. To solve this problem, this article proposes an improved auxiliary classifier generative adversarial network (AC-GAN) architecture, namely, auxiliary classifier variational autoencoder Radar propagation, land and sea clutter, atmospheric models, attenuation due to gas, fog, rain and snow In radar systems, detection performance is always related to target and clutter models. First, within the framework of a multiplicative model, the reciprocal of the gamma distribution is used to describe the texture component of sea clutter in SeaSurface defines a sea surface object belonging to a radarScenario. However, due to the separation of the transmitter and the receiver, the clutter exhibits severe range dependence in both Doppler and spatial-angle domains. Modern radars have become increasingly more complex and less tractable for mathematical analysis. Next, it discusses the reflectivity of sea surfaces, investigating the Sep 1, 2019 · In order to use simulated sea clutter for evaluating new detection algorithms, it must represent the statistical characteristics that are present in real data. The Sea clutter reflectivity also includes the propagation affects from the sea surface. Whether the clutter model is accurate and flexible or not, is an important criterion accessing the Abstract: In the sea–land clutter classification of sky-wave over-the-horizon-radar (OTHR), the imbalanced and scarce data lead to a poor performance of the deep learning-based classification model. 6 demonstrates the image of first frame playback data, and Fig. To this end, this paper proposes a Sep 2, 2020 · Meanwhile, it is the evaluation of sea clutter. The MATLAB function gammainc(x, a) is limited to non-negative a, so the Fortran function DGAMIC from the This example will introduce a sea clutter simulation for a maritime surveillance radar system. It can be seen from the greyscale of the image that there is a strong sea clutter in the near area of radar detection, and there are buildings and other ground clutter around the shore-based system. Next, it discusses Simulate sea clutter for a maritime surveillance radar system and calculate the clutter-to-noise ratio (CNR). However, in traditional zero memory nonlinearity (ZMNL) method, the Calculate the RCS of a clutter patch and estimate the clutter-to-noise ratio (CNR) at the receiver. , "Littoral and Bistatic sea clutter" Sea Clutter seminar, DGAC Sea-surface small target detection in high-resolution sea clutter is always an intractable problem. This means, the scenario “moves away”, i. Jan 1, 2014 · These sea clutter spikes need to be characterized to distinguish them from small targets. This example shows how to generate monostatic surface clutter signals and detections in a radar scenario. For example, a ground moving target indicator (GMTI May 25, 2022 · It also enables you to develop signal processing techniques for detection and data processing algorithms for tracking and image formation while accounting for the clutter due to land and sea surfaces. Since R2021a; Open Live Script; Modeling Target Position Errors Due to Refraction. Assume that the patch has a normalized radar cross section (NRCS) of 1 m²/m² and is 1. As a result, they cannot be used continuously when modelling radar Aug 22, 2019 · Figs. Sep 30, 2023 · The Doppler spectra of sea echoes, which contain abundant information on floating scatterers, are important for exploring the characteristics of sea clutter. Radar Reflectivity of Land and Sea, 3rd Ed. Extensive sea clutter was Oct 10, 2022 · Impact of sea clutter nonstationarity on disturbance covariance matrix estimation and CFAR detector performance[J]. Then, use the scenario seaSurface method to add the rectangular sea region and the radar reflectivity model to the scenario. The constantGammaClutter System object™ simulates constant gamma clutter reflected from homogeneous terrain for a monostatic radar transmitting a narrowband signal into free space. Use This example will introduce a sea clutter simulation for a maritime surveillance radar system. The surface is a simple 400-by-400 meter rectangle. For example, a ground moving target indicator (GMTI Once the number of clutter patches gets large, the data can no longer be fit into the GPU memory. A machine learning based processor, associating the artificial neural A spaceborne bistatic surveillance radar system, which may increase the target radar cross section through a large bistatic angle, can effectively improve the performance of small air moving target indication. Table 3 gives the running time of the different detectors by MATLAB. Analysis on the spectrum width and shift of multi-band can be done. Over the past decade, the development of new radar waveforms and signal processing algorithms has been assisted by an increasingly good understanding of the characteristics of sea clutter. Logrado Expand. Aug 1, 2023 · The clutter dictionary obtained after training contains the feature of sea clutter. The reliable way of detecting the They used sea clutter data for experimental analysis in the MATLAB environment. No special toolboxes are used, thus this should work in virtually any Matlab or GNU Octave install. Feature-based detection in multidimensional feature spaces is recognized to be an effective way, and therein, learning algorithms with controllable false alarm rate play an important role. mqtiq xss cnlht odtqx nqrmsn mxizhv jpyx mstv sqfx jmofu