• Ocean and Polar Research
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• v.38 no.4
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• pp.325-330
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• 2016

Partial high frequency bands were allocated to the operation of ocean surface radars that monitor the sea surface currents and waves in WRC-12. On that basis, government-related organizations revised the table of domestic frequency allocation. In order to study radio environments in the allocated bands for ocean radar, tests of the radio signal spectrum were carried at 7-sites using the receiver of the ocean surface radar system operated with a shutdown of the transmitter for 10-60 min. The results showed that no serious radio noises occur at 25 and 43 MHz bands, indicating a good radio environment for the ocean surface radar operation. However, at 13 MHz band, it was difficult to generate stable and confidential data from the ocean surface radar because serious radio noises occurred continuously.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.7
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• pp.536-546
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• 2003

We propose an object extraction technique adequate for the radial shape's radar signal structure for the purpose of implementing ARPA(Automatic Radar Plotting Aid) installed in the vessel. The radar signal data are processed by interpolation and accumulation to acquire a qualified image. The objects of the radar image have characteristics of having different shape and size as it gets far from the center, and it is not adequate for clustering generally. Therefore, this study designs a new vigilance distance model of elliptical shape and adopts this model in the ART2 neural network. We prove that the proposed clustering method makes it possible to extract objects adaptively and to separate the connected objects effectively.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.4
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• pp.482-490
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• 2017

The radar signal processing procedure is divided into the pre-processing such as frequency down converting, down sampling, pulse compression, and etc, and the post-processing such as doppler filtering, extracting target information, detecting, tracking, and etc. The former is generally designed using FPGA because the procedure is relatively simple even though there are large amounts of ADC data to organize very quickly. On the other hand, in general, the latter is parallel processed by multiple DSPs because of complexity, flexibility and real-time processing. This paper presents the radar signal processor design using FPGA which includes not only the pre-processing but also the post-processing such as doppler filtering, bore-sight error, NCI(Non-Coherent Integration), CFAR(Constant False Alarm Rate) and etc.

• Journal of Applied Reliability
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• v.18 no.2
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• pp.184-191
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• 2018

Purpose: The purpose of this study is to propose a method to calculate the optimal preventive maintenance cycle of radar used in the aviation weapon system of ROKAF. Methods: A hybrid model is used to estimate the optimal preventive maintenance cycle in a system that can perform condition based predictive maintenance (CBPM) through continuous diagnosis. The failure data of the radars operating in the military were used to calculate the reliability. Results: According to the research results, the reliability threshold of the radar began to decrease after 5 flights, and decreased rapidly after 12 flights. Since the second check, costs have continued to decline. Conclusion: A method is proposed to determine the cycle of optimal preventive maintenance of radar within operational budget through modeling results between reliability limit and cost for radar. The results can be used to determine the optimal preventive maintenance cycle and frequency of various avionics equipment.

• Journal of IKEEE
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• v.23 no.2
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• pp.395-402
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• 2019

In this paper, we implemented an Ultra-Wideband radar system using Stripmap Synthetic Apertrure Radar algorithm to recognize objects inside a box. Different window functions such as Hanning, Hamming, Kaiser, and Taylor functions to improve image recognition performance are applied and implemented to radar system. The Ultra-Wideband radar system with 3.1~4.8 GHz broadband and UWB antenna were implemented to recognize the conductor plate located inside 1m3 box. To obtain the image, we use the propagation data in the time domain according to the 1m movement distance and use the Range Doppler algorithm. The effect of different window functions to improve the recognition performance of the image are analyzed. From the compared results, we confirmed that the Kaiser window function can obtain a relatively good image.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.3
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• pp.57-62
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• 2022

Recently, the tracking radar continues research to develop a new operation algorithm that can acquire and track a target in various environments. In general, modeling similar to the real target and environment is used to develop a new operation algorithm, but there is a limit to modeling the real environment. In this paper, a RAW data storage device was developed to efficiently develop a new operation algorithm required for the tracking radar using millimeter wave to acquire and track the target. The RAW data storage equipment is designed so that the signal processing device of the tracking radar using millimeter wave can save the RAW data output from 8 channels to OOOMSPS. RAW data storage equipment consists of data acquisition equipment and data storage equipment. The data acquisition equipment was implemented using a commercial Xilinx KCU 105 Evaluation KIT capable of high-speed data communication interface, and the data storage equipment was implemented by applying a computer compatible with the commercial Xilinx KCU 105 Evaluation KIT. In this paper, the performance of the implemented RAW data storage equipment was verified through repeated interlocking tests with the signal processing device of the millimeter wave tracking radar.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.3
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• pp.497-502
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• 2018

An analog to digital converter(: ADC) has been designed to extract video signals of marine X-band radar and convert to digital signals in order to produce rainfall information. X-band weather radars are suitable for high temporal-spatial resolution observations of rainfall over local ranges but they are very expensive and require professional management. The marine radars with 10-2 cost facilitate data collection and management as well as economic benefits. To validate the usefulness of the developed ADC, comparative observations were made with weather radar for short term precipitation cases. The rainfall distribution of marine radar observations are consistent with that of weather radar within a radius of 15 km. This demonstrates the usability of marine radar for rainfall observations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1B
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• pp.7-14
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• 2006

The radar relationship was estimated for the selected rainfall event at Yeongchun station within Chungjudam basin where the discharge record was the range of from 1,000 CMS to 9,000 CMS. By calibrating the rainfall coefficient parameter estimated by radar relationship in small hydrology basin, rainfall with the topography properties was calculated. Three different rainfall estimation methods were compared:(1) radar relationship method (2) Thiessen method (3) Isohyetal method (4) Inverse distance method. Basin model was built by applying HEC-GeoHMS which uses digital elevation model to extract hydrological characteristic and generate river network. The proposed basin model was used as an input to HEC-HMS to build a runoff model. The runoff estimation model applying radar data showed the good result. It is proposed that the radar data would produce more rapid and accurate runoff forecasting especially in the case of the partially concentrated rainfall due to the atmospheric change. The proposed radar relationship could efficiently estimate the rainfall on the study area(Chungjudam basin).

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.4
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• pp.353-357
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• 2006

The vehicle detection method using pulse radar has the advantage of maintenance in comparison with loop detection method. We propose the pulse radar signal processing algorithm in which we devide the trace. data from pulse radar into segments by using SSC concept, and then construct the sectors in accordance with period and amplitude of segments, and finally decide the vehicle detection probability by applying the SSC parameters of each sectors into the discriminant function. We also improve the signal processing time by reducing the quantities of processing data and processing routines.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.178-181
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• 2004

The Tropical Rainfall Measuring Mission (TRMM) is an US-Japan joint space mission to observe tropical and subtropical rainfall. This satellite is equipped with the world's first precipitation radar that operates at 13.8 GHz. We introduce the TRMM precipitation radar (PR) system, along with the PR data processing and analysis algorithms, and some observation results obtained by the TRMM PR. It is concluded that the TRMM PR can give quite useful rainfall data for the understanding of global climate changes, meteorology, climatology, atmospheric science, and also for the studies of satellite communication.