• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.175-177
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• 2006

According to the recommendation of International Maritime Organization, the Ministry Of Maritime Affairs and Fisheries (MOMAF) of Korea provides the real time Differential Global Positioning System service using maritime radio beacon from 1999. Due to the benefit of DGPS service, the need of this system is increased from various user groups for acquiring the better accuracy and integrity. Therefore, MOMAF has extended their service to inland by installing the additional 6 DGPS stations. This nationwide DGPS service will be fully deployed at 2007. In addition to the extension of service area, MOMAF has a plan to upgrade their nationwide DGPS to High Accuracy Nationwide DGPS (HANDGPS). The planned HANDGPS service of Korea will be a kind of long range RTK or Wide Area RTK techniques to provide under 1m accuracy and start their service from 2009 using the various broadcasting and communication media like as radio beacon, Wibro, Digital Multimedia Broadcasting, High Speed Packet Data Access. The introduction of nationwide DGPS system of Korea and its evolution plan will be addressed in this paper. The research activities related with HANDGPS in Korea is also presented.

• Journal of information and communication convergence engineering
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• 제10권2호
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• pp.97-102
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• 2012

The differential global positioning system (DGPS) transmits a GPS enhancement signal using a top-loaded monopole antenna in the medium frequency range. The top-loaded antenna in the medium frequency band can attain a radiation efficiency on the order of 10%. The antenna ground plane characteristics affect the antenna radiation efficiency. To improve the radiation efficiency, it is necessary to install the antenna on a ground plane with large enough physical dimensions and good conductivity. The antenna radiation efficiency is a primary factor in determining the DGPS service area. The service area of the DGPS using a medium frequency band is dominantly affected by the antenna radiation efficiency. To determine antenna radiation efficiencies accurately, the antenna radiation efficiencies of DGPS are deduced from the propagation power in this paper. Based on the deduced antenna radiation efficiencies, the service area for the Korean nationwide-DGPS is analyzed and evaluated.

• 한국항해학회지
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• 제24권3호
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• pp.157-165
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• 2000

When the GPS system was come to the operation, the U.S Coast Guard initiated development of differential GPS system based on a marine radiobeacon. It has rapidly been spread out to many countries. DGPS equals to P(Y) code in a positioning accuracy. USA has recently determined to expand the coverage of DGPS to inland in order to install a nationwide DGPS chain. Korea is under processing for improving the DGPS as a nationwide positioning system. Before expanding the service area inside Korea, we need to verify the relation between the field strength and DGPS accuracy for the service area. The Japanese DGPS data is received in the southern Part of the Korean peninsula. The Korean DGPS was not a complete system, so we selected the Japanese DGPS data as a model for the study. This paper investigate accuracy and reliability characteristics of RBN/DGPS over the effective service area. Through the experimental and simulation study, we obtained the reliable and stable positioning accuracy in the southern part of the Korean peninsula. In addition, the characteristics of RBN/DGPS were examined in the land over the effective coverage from Japan. The results would be a basic reference to research the RBN/NDGPS in Korea.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 제 25회 정기총회 및 추계학술발표회
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• pp.23-28
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• 2000

The DGPS is used to improve the accuracy of the GPS by determining the positioning error data known locatio and subsequently transmitting the determined error, or corrective factors, to users of the GPS operating in the same geographical area. The accuracy of the DGPS available to real0time users is published in the Federal Radio-Navigation Plan to be better than 10 meters, although users often experience accuracies of better than 3 meters. USA recently decided to expand the marine DGPS service for land applications and initiated the Nationwide DGPS chain. Korea is processing for improving the marine DGPS. We have not achieved Full Operational Capability. But after announcing FOC, we have to begin expansion of DGPS into land. This paper investigate the availability of marine DGPS in land. The results will provide a basic guide for estimation of a propagation loss of the marine DGPS frequency in land.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.263-265
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• 2015

미국은 우리나라와 같이 전국망 DGPS 인프라를 운영하고 있는 국가 중에 하나로 DGPS 서비스를 해양분야 뿐만 아니라 육상분야에도 제공하고 있는 대표적 국가이다. 지난 8월 18일 미 정부는 연방공보를 통해 현재 운영 중인 전국망 DGPS 서비스의 대규모 개편 계획을 공표한 바 있다. 공표된 계획에 따르면, 2016년 1월 15일부로 육상에서의 DGPS 서비스는 중단되고, 해양에서의 DGPS 서비스도 크게 영향을 받을 것으로 예측되고 있다. 따라서 본 논문은 우리나라와 유사한 형태의 DGPS 인프라를 운영하고 있는 미국이 전국망 DGPS 서비스를 개편하게 된 배경과 원인에 대해 살펴본다. 그리고 미국이 공표한 계획의 실행 전망과 쟁점에 대해 알아본다. 마지막으로 미국의 NDGPS 서비스 운영정책 변화가 우리에게 전달하는 시사점을 제시한다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.268-269
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• 2015

해양수산부 해양측위정보원은 현재 총 17개소의 DGPS 기준국을 운영 중이다. 그러나 남한의 면적을 고려할 때 지나치게 많은 기준국을 운영하고 있다는 판단에서 3-4개소의 기준국만으로 균일한 정확도의 DGPS 서비스가 가능하도록 보정정보를 효율적으로 생성하는 방법을 적용하였다.

• Journal of information and communication convergence engineering
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• 제10권3호
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• pp.225-230
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• 2012

The Korean nationwide differential global positioning system (NDGPS) reference station transmits a global positioning system (GPS) enhancement signal using minimum shift keying modulation with a 200 bps data rate. The ocean-based DGPS covers the service area of 100 NM with 300 W output power; on the other hand, the land-based DGPS transmits the output power of 500 W, which covers the service area of 100 km. The DGPS reference stations with high output power can radiate spurious signals, which may act as interference sources affecting the other DGPS reference stations or the wireless ground stations that utilize the medium frequency band. In this paper, the radiation spectrums of the DGPS reference stations are measured and analyzed in the spurious domain. The DGPS radiation spectrums are evaluated from the perspective of the interference effect.

• 한국군사과학기술학회지
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• 제14권5호
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• pp.788-797
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• 2011

This paper analyzes the accuracy on the approach and landing of aircraft to an airport through comparison with airbase Precision Approach Radar and aircraft track data of DGPS equipped in aircraft. The proposed analysis result could be a basis for verifying the possibility that DGPS can be utilized in Airbase precision approach and landing. Position identification capability of widely used commercial DGPS is fairly accurate on latitude and longitude, while there is a slight error for being used in an airbase accurate approach and landing of Category I precision when it comes to altitude. Thus, we tested accuracy by analyzing actual flight track data of high performance aircraft to verify the accuracy of the airbase approach and landing using DGPS. Through the research, we developed instrumentation to compare PAR track data with DGPS track data, which can be used in reducing the number of PAR verification Flight utilizing it as a system measuring PAR accuracy at PAR installation phase.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 춘계종합학술대회
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• pp.732-736
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• 2001

DGPS는 미 군사용 신호를 이용한 정밀도 수준을 제공할 수 있는 위성항법 시스템으로써 30여개 국가에서 해양용 국가망 위주로 구축되고 있다. 특히 미국은 해양용 DGPS 국가망을 내륙으로 확장한 NDGPS(Nationwide DGPS)체계 구축을 2002년까지 완성할 예정이다. 우리나라도 해양용 국가망을 운영하여 해양활동을 하는 사용자에게 3차원 고정밀 위치정보를 제공하고 있다. 근래에 우리나라 연안에 구축되어 사용중인 해양용 라디오비이콘형 DGPS망을 육상으로 연계한 서비스범위 확대방안이 논의되고 있다. 본 연구는 NDGPS에 대한 기초연구로서 운용중인 DGPS 기준국신호를 모델로 하여 해상 전파 설계치 대비 거리 및 지형변화에 따른 전계강도 변화를 분석하였다.

• 한국항해항만학회지
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• 제32권8호
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• pp.611-619
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• 2008

국토해양부에서는 해양 DGPS 기준국가 연계하여 전국망 위성항법보정시스템(NDGPS) 구축 사업을 추진 중에 있으며, 2008년 춘천기준국이 설치 완료되면 우리나라 전역에서 실시간 DGPS 측위 정보를 이용할 수 있다. 따라서 DGPS 측위 정보의 이용 활성화를 위하여 DGPS의 측위 정확도를 측정 분석하였다. 실시간 DGPS 측위 정확도는 정적 측정시 평면상 RMS(Root Mean Square) 오차는 0.42m, 동적 측정시 평변상 RMS 오차는 0.48m로 분석되었으며, RTK에 의한 비교 측정 분석도 병행하였다. 그 결과 위성항법보정시스템(DGPS)은 높은 정확도를 요하는 GIS구축사업 분야에 직접적으로 이용될 수 없으나, 실시간 측위 정보를 필요로 하는 GIS활용 분야에서는 DGPS가 다양하게 이용될 수 있을 것이다.