F db frequency band terrain type vhf uhf lband sband xband. The simulation of ground clutter is the key and knot problem in radar simulation system. Barrios abstractradar clutter in a nonstandard atmosphere usually. This solution avoids selfinterferences while maintaining the hardware simplicity and performance of an isolated lfmcw sensor. Ground clutter mitigation with moving target indication.
Polarimetric backscattering behavior of ground clutter at x, ka, and wband. Lowangle radar land clutter measurements and empirical models j. These radars can distinguish between signal interference, clutter, and the signal with the use of a receiver to transmitter feedback system. Lee department of electrical and computer engineering duke university date. How radar detect, track, and attack through the clutter. Lowangle radar land clutter pdf free download epdf.
Low grazing angle rre, git, sittrop, tsc, hybrid, nathanson. Finally, a radar network has been developed to demonstrate that the use of lowcost olfmcw radar transceivers in a. Good background in probability, random variables, and stochastic processes. Icm arises when wind blows on vegetation or other clutter sources. Clutter can also be weatherrain, animals, chaff and atmospheric turbulences. The sidelobe clear and clutter regions can also be expressed in terms of the aspect angle with respect to the target,14 as shown in fig. Pdf bistatic radars are parts of coherent multistatic radar systems for air targets positioning and tracking. When a low tilt angle is used for vad work, most of the gates used for determining the wind profile will be beyond this distance, and the problem of ground. Along the himalayan range, the clutter interference levels are increased by 7501,000 m. Radar clutter modeling and analysis pdf free download. Pdf model comparison of bistatic radar clutter researchgate.
Clutter can be anything from trees, ground, ocean waves, anything that can produce an unwanted echo return to the radar. Army national ground intelligence center, 220 seventh street. Luke rosenberg presented a tutorial on high resolution land and sea clutter at radar 2015, washington dc, jointly with maria greco. The performance of detection can be improved via utilizing the multipath echoes.
For instance, a sine wave witha frequency exactly equal to the prf. Radar systems course 44 clutter 1112009 ieee new hampshire section ieee aes society references 1. You can be the book low angle radar land clutter measurements and empirical models system to do them send you was based. Banks dissertation submitted in partial ful llment of the requirements for the. In our models the grazing angles are computed accounting for. Modeling the amplitude distribution of radar sea clutter mdpi. Nixonb asubmillimeterwave technology laboratory, university of massachusetts lowell lowell, ma 01854 bu. The clutter depth from the surface clutter free bottom.
Minefield overwatch using moving target indicator radar. Ground clutter measurements for surfacesited radar dtic. The depression angle used in billingsleys low angle radar land clutter model is the angle below the radar at which a clutter patch is observed by the radar. Book low angle radar land clutter measurements and. P billingsleyicmfd,fc,wspeed calculates the clutter doppler spectrum shape, p, due to intrinsic clutter motion icm at doppler frequencies specified in fd. This clutter sending back signals makes it difficult to find the target you really want to detect. 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 models frequency and grazing angle ranges.
Radar land clutter constitutes the unwanted radar echoes returned from the earths surface that compete against and interfere with the desired echoes. Radar, radar simulation, clutter generation, coherent weibull, weibull pdf, weibull statistics. Radar sea clutter modelling and applications instructors. Physical scale modeling the millimeterwave backscattering. But for the life of me, i cant recall where they got these data files from. Simulation of the radar ground clutter based on dem. Clutter echoes can be many orders of magnitude larger than target echoes. Pdf radar clutter in a nonstandard atmosphere usually is modeled based on a single grazing angle at each range. Just make sure to ask for it in the notes section at checkout.
The results show radar clutter can be mitigated either by reducing the ground area illuminated by the antenna, in the case of surface clutter, or by reducing the pulse duration, in the case of volume clutter. This example shows the design of a moving target indication mti radar to mitigate the clutter and identify moving targets. The magnitude of the backscattered signal is characterized by the normalized radar crosssection. Optimised scantoscan integration techniques for low. Conventional scantoscan integration techniques for detecting small target have been discussed in the literature 2. However, care must be taken to not decrease coverage of distant, lowangle targets. This function uses billingsleys model in the calculation. Impact of radar tilt and ground clutter on wind measurements in clear air. The angles used in billingsleys low angle land clutter model are depression angles, which do not include the local terrain slope. Parasitic returns that enter the radar through the antennas main lobe are called main lobe clut.
The simulation of ground clutter based on dem is studied. One of the biggest challenges in cognitive radars is modeling cluttering and adapting to its surroundings. This thesis looks into land clutter modeling distributions and discrete clutter modeling techniques. Clutter data geographic information systems stack exchange. Physical scale modeling the millimeterwave backscattering behavior of ground clutter a. Below is an example radar images using the lowest tilt angle 0. Cfb level is approximately 1,000 and 2,000 m at the nearnadir and swath edge, respectively. Billingsley solves the problem of radar land clutter, where echoes from the earths surface interfere with radar target echoes. The power levels of the radar returns from these small targets are equal or less than those of clutter peaks.
Effect of clutter interference in surface rainfall. At some instance during the propagation of the pulse, a pulsed radar will illuminate a patch on the surface, defined for low grazing angles to a first order by the pulse length, the antenna azimuth beamwidth and the local grazing angle. Low angle radar land clutter measurements and empirical. Multiple radar target tracking in environments with high. Airborne radars for surveillance and weapon delivery.
Ground clutter spectra for low, medium and high prf radars. Prerequisites good background in mathematics, physics. Chapter 11 radar clutter modeling and analysis these gaussian variables will have a mean of 0 and variance of 0. Clutter is a term used for unwanted echoes in electronic systems, particularly in reference to radars. Santapietro the mitre corporation 145 wyckoff road eatontown, nj 07724 abstract traditional antipersonnel ap land mines are an effective military tool, but they are unable to distinguish friend from foe, or civilian from military. This report examines the nature of lowangle radar ground clutter as it has come to be understood. For smooth terrain and sea surface and low grazing angles. Cfb level for dpr is generally high over land as compared with that of pr. Please note that currently the pdf files are windows only, but if you use a different operating system, we can still provide you with the file. Comparison of a transhorizon littoral clutter model with. Barrie billingsley lincoln laboratory massachusetts i.
Keywords bistatic radar, land clutter, effective clutter cross. Mapping of weather radar ground clutter using the digital elevation model srtm. Abstractin this paper, a practical mean reflectivity model of radar land clutter lc for the complex system design of groundbased radars involved in against low. The result of 20 years of research at mit lincoln lab, this book is of the most significant tehcnological consequence for the industry. Moses the ohio state university, department of electrical and computer engineering 2015 neil avenue, columbus, oh 43210, usa abstract we present a physicallybased clutter model for low frequency synthetic aperture radar that includes both. Thus, if there are problems with clutter, it may be beneficial to increase the tilt of the antenna. First, the reflection coefficient considering the curved earth effect is derived. On the use of lowcost radar networks for collision. Lowgrazing angle detection in compoundgaussian clutter. The spanish air force have procured 10 3d long range lanza radars for use in its.
Littoral model, radar clutter, radar modeling, radar propagation, terrain effects. Polarimetric backscattering behavior of ground clutter at. For a radar system, clutter refers to the received echoes from environmental scatters other than targets, such as land, sea or rain. Minefield overwatch using moving target indicator radar anthony donadio, robert ewing, william kenneally, john j. Clutter definition clutter is a term used to describe any object that may generate unwanted radar returns that may interfere with normal radar operations. Li shasha automation institute, harbin engineering university, harbin, heilongjiang province, china. It unifies and integrates results which should enable prediction of land clutter effects in surface radar, needed for lowflying aircraft. Multiple radar target tracking in environments with high noise and clutter by samuel p. Such echoes are typically returned from ground, sea, rain, animalsinsects, chaff and atmospheric turbulences, and can cause serious performance issues with radar systems. Radar spacetime processing for rangefolded spreaddoppler clutter mitigation by william w.
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