• Journal of Advanced Navigation Technology
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• v.8 no.1
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• pp.38-47
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• 2004

To achieve functions of doppler measurement, MTI(Moving Target Indicator), high-resolution, and others in radar system, all circuits of transmitter and receiver are to be performed in coherent system. In this paper, we use TWTA(Traveling Wave Tube Amplifier), STALO(Stable Local Oscillator) and COHO(Coherent Oscillator) to design of coherent radar transceiver, and calculates noise figure of designed receiver. Using radar equation calculated noise figure, maximum detecting range of each transmitting mode can be calculated.

• Journal of Advanced Navigation Technology
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• v.3 no.2
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• pp.120-131
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• 1999

For the phase measurement in the radar system using the magnetron pulse source, the STALO (Stable Local Oscillator) frequency need to be controlled to provide the stable intermediate frequency. In radar receiver, AFC(Automatic Frequency Control) circuit detects the transmitting frequency change and controls the STALO frequency to keep the intermediate frequency stable. In this paper, we designed and implimented AFC circuits for radar receiver. The frequency deviation is detected and compared with the reference frequency and the STALO frequency is controlled by the digital command signal.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.11a
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• pp.323-324
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• 2022

This paper explains the comparison results of surface current measurement using X-band Radar image through analysis. Measurements were carried out from February 2022 using the X-band Radar for marin ships installed at Sokcho Beach. Based on the Korea Hydrographic and Oceanographic Agency ocean observation buoys, the accuracy of surface current(current speed) measurement was verified through comparison and analysis of measurement data.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.119-120
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• 2019

In order to verify the accuracy of wave measurement of the wave instrumentation system using X-band navigation radar, The validity of the results was obtained by analyzing the significant wave height around Ulleungdo. Especially, The correlations between the radar, wave height buoy and marine buoy for wave measurements were analyzed in season.

• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.509-516
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• 2022

Recently, ships have begun using the Asterix CAT 240 format as a method for transmitting radar image data to other devices. However, the Asterix format has a flexible structure that can be defined by the user, and a format structure defined as unsuitable for ship radar operation may undesirably increase navigational equipment network traffic or reduce stability. Therefore, to reduce the traffic of the navigation network and enhance the stability, a method of defining the optimized Asterix CAT 240 format with an appropriate setting value according to the performance of the radar scanner and display device was studied.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.103-105
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• 2017

e-Navigation, which is scheduled to be implemented in 2019 centered on IMO, is actively conducting researches worldwide and various marine systems are being developed. Ship INS will be integrated with various navigation systems such as RADAR, ECDIS, BAM, etc. in order to support e-navigation system, and there is a great need for integrated operation and management. In this research, introduce a research on the integration method of platform - based ship navigation equipment that can operate, expand, maintain and repair various ship systems efficiently.

• Journal of Navigation and Port Research
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• v.44 no.2
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• pp.110-118
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• 2020

With the expansion of the shipping and port logistics industry in the 21st century, the traffic density is continuously increased because of the increase in volumes of world sea freight and fleets, as well as the increase in the causes of potential marine accidents, such as ship collisions and stranding. Accordingly, the International Maritime Organization (IMO) has requested that the installation and operation of VTS should be applied in areas with high risk of marine traffic, and the request should be included as one of the Safety of Life at Sea (SOLAS) regulations. In this paper, the fundamental requirements of the radar system for vessel traffic services were analyzed and the analyzing factors were based on the IALA guideline.s This paper also includes results for the requirement and recommendation analysis on detection distance, target separation, and the target position accuracy of X-band radar. Also, to check if it satisfies the requirement of detection distance, range and azimuth separation of small point targets, and target position accuracy from the IALA guidelines, the test was conducted through the radar image acquired at the VTS center, and hence, the validity of the technical performance requirements was confirmed.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.10a
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• pp.71-78
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• 2006

The image of an object obtained by the radar is not corresponding to its true shape, because the image of an object observed by the radar is receiving an influence such as multiple-reflections and expanded in bearing because of the beam width of a radar. In addition, a radio wave does not hit the entire surface of an object. Therefore, the image of the front side of a ship facing a radar antenna corresponds to its true shape. In this paper, a method to estimate a ship's shape by means of the integration of the front parts of images obtained from radars is proposed. In addition, a matter, which is observation error of each radar, in using multi-radars, and the process included in the proposed method for solving the matter, are described. As a result of the experiment, the accuracy of about 3 degrees in ship's heading and about 14 meters in length and about 9 meters in beam was obtained.

• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.486-490
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• 2018

Radar Beacons are marine aids that helps the navigators avoid dangers such as dangerous rocks, heavy fog, nighttime, etc. when sailing. The existing antenna was researching on the development of the advanced radar Beacon (Enhanced Radar Beacon) for the improvement of the next generation racon with the AIS (Automatic Identification System) function.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.40-41
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• 2023

This paper introduces the design of detection, recognition, and tracking algorithms for VTS radar image-based objects. The detection of objects in radar images utilizes artificial intelligence technology to determine the presence or absence of objects, and can classify the type of object using AI technology. Tracking involves the continuous tracking of detected objects over time, including technology to prevent confusion in the movement path. In particular, for land-based radar, there are unnecessary areas for detection depending on the terrain, so the function of detecting and recognizing vessels within the region of interest (ROI) set in the radar image is included. In addition, the extracted coordinate information is designed to enable various applications and interpretations by calculating speed, direction, etc.