• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.2
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• pp.109-115
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• 2020

As the maritime targets that threaten allies become lower, smaller, and faster, the need for analysis and modeling of clutter according to sea state increases. Clutter according to the sea state has a great influence on radar performance, such as lowering the probability of detection of low-altitude small maritime targets. In this paper, to analyze the detection performance of a multi function radar for a ship, a sea clutter model suitable for the radar operating environment is selected from several sea clutter models, and analysis of low-altitude, small target detection under a clutter is performed. By using the actual data of the already mounted radar for maritime target detection, four known clutter models have been implemented for each sea state and compared with the actual data. Through this, by selecting a clutter model that best reflects the actual radar environment, reliability of the clutter model is improved. Subsequently, the selected model is used to detect the detectable distance to the low-altitude small target.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.5
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• pp.407-417
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• 2019

When a free-falling ballistic missile intercepts a maritime target in a sea clutter environment at high grazing angle, detection performance of the ballistic missile's seeker can be rapidly degraded by the effect of sea clutter. To solve this problem, it is necessary to verify the performance of maritime target detection via simulations based on various scenarios. We accomplish this by applying a two-dimensional cell -averaging constant false alarm rate detector to a two-dimensional radar image, which is generated by merging a sea clutter signal at high grazing angle with a maritime target signal corresponding to the signal-to-clutter ratio. Simulation results using a computer-aided design model and commercial numerical electromagnetic solver in various scenarios show that the performance of maritime target detection significantly depends on the grazing and azimuth angles.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.2 s.25
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• pp.87-95
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• 2006

The performance of a microwave missile seeker and radar operating in an air-to-air look-down mode is strongly influenced by the presence of ground clutter In order to correctly account for the effects of ground clutter, it is required to develop a model capable of representing clutter characteristics as a function of range and/or frequency. In this paper, a program to estimate the clutter reflectivity for various ground conditions is developed, using the actually measured data and the data available from open literatures. In addition, clutter characteristics measured for various ground conditions such as sea, agricultural area, urban city and industrial area through the captive flight tests are presented.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.3 no.2
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• pp.66-78
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• 1992

Available data for the radar clutter, and the empirical and the theoretical models for the radar clutter have been collected and analyzed. Data sets and models from the remote sensing field have been studied extensively. Although the grazing angles used in remote sensing is larger than the angles normally encountered in radar clutter application, remote sensing field has the merit of abundance of data in much more detailed target classes. The remote sensing model is also superior to the normally used clutter models in the sense that each target class has its own model, rather than being generally characterized by assumed roughness parameters.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.6
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• pp.507-517
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• 2019

Multi-function radar(MFR) is a system that uses various functions such as detection, tracking, and classification. To operate the functions in real-time, the detection stage in MFR usually uses radar signals for short measurement time. We can utilize several conventional detectors in the MFR system to detect low radar cross section maritime targets in the sea-clutter; however, the detectors, which have been developed to be effective for radar signals measured for a longer time, may be inappropriate for MFR. In this study, we proposed a modelling technique of sea-clutter short measurement time. We combined the modeled sea-clutter signal with the maritime-target signal, which was obtained by the numerical analysis method. Using this combined model, we exploited four independent detectors and analyzed the detection performances.

• Korean Journal of Remote Sensing
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• v.34 no.2_2
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• pp.431-437
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• 2018

We analyzed the feasibility of detecting wave gliders moving on the sea surface using SAR images. For the experiment, a model was constructed and placed on the sea using a towing ship before and after the satellite observation time. In the acquisition of KOMPSAT-5 image, high resolution SAR data of spotlight mode was collected considering the small size of wave glider. As a result of the backscattering intensity analysis around the towing ship along with wave glider, several scattering points away from the ship were observed, which are not strong but clearly distinguished from the surrounding clutter values. Considering the distance from the center of the ship, it seems to be a signal by the wave glider. On the other hand, it is confirmed that the wave glider can be detected even at the very low false alarm rate ($10^{-6}$) of the target detection using CFAR. Although the scatter signal by the wave glider could be distinguished from the surrounding ocean clutter in the high resolution SAR image, further research is needed to determine if actual wave gliders are detected in various marine environments.