• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.86-86
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• 2017

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.146-146
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• 2017

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.145-145
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• 2017

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.87-87
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• 2017

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.85-85
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• 2017

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.188-189
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• 2017

In recent years, the development of GPS navigation system (GNSS), which has been developed not only by US GPS but also by major countries, is entering its final stage. It is time to change the infrastructure and technology system to correct each satellite system. To do this, we analyze the performance of the differential information provided by National Maritime PNT Office for GLONASS currently operating in its normal orbit, and present the its feasibility.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.11a
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• pp.175-176
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• 2023

1973년 최초로 서비스를 시작한 GPS는 전 세계 60억명 이상이 사용 중이며 거의 모든 사업에 큰 영향을 미치고 있으며, 자동차, 농업, 해양, 일반 안전, 레저활동, 지형공간정보, 항공, 금융, 통신 등 산업 전반에 걸쳐 경제적 이익이 약 1조4천억 달러에 이르는 글로벌 시스템이라 할 수 있다. 최근에는 미국의 GPS 뿐만 아니라 유럽, 러시아, 중국 등 세계 주요국들은 자국의 독자 위성항법시스템을 구축하고 있으며, PNT 정밀성 향상을 위한 위성항법보강시스템의 개발 또한 주요국 중심으로 이루어지고 있다. 4차산업기술의 발달로 인해 다양한 산업의 상용화와 대중화에 따라 PNT 정보의 고정밀, 고신뢰에 대한 수요도 급증하고 있으며, 이에 대한 응용기술 분야에 대한 시장도 급속하게 성장하고 있다. 우리나라에서도 KASS와 같은 위성항법보강시스템 구축을 추진하고 있으며, 향후 독자 위성항법시스템인 KPS의 개발도 진행중에 있다. 그러나 고도 23,000km에서 송출하는 위성신호의 전파교란·기만에 대한 취약성과, 도심지와 같은 위성신호 수신이 열악한 환경에서는 고정밀·고신뢰 PNT 정보를 제공하기가 현실적으로 어려운 실정이다. 이러한 GPS의 취약성을 보완하기 위해 지상기반의 PNT 정보제공 시스템 구축의 필요성이 증대되고 있으며, 전세계적으로 상호보완적 PNT 시스템의 구축·기술개발에 대한 연구가 다양하게 이루어지고 있다.

• Journal of Positioning, Navigation, and Timing
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• v.11 no.4
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• pp.269-277
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• 2022

In this paper, we overview the system development status of the national maritime precise point positioning-real-time kinematic (PPP-RTK) service in Korea, also known as the Precise POsitioning and INTegrity monitoring (POINT) system. The development of the POINT service began in 2020, and the open service is scheduled to start in 2025. The architecture of the POINT system is composed of three provider-side facilities-a reference station, monitoring station, and central control station-and one user-side receiver platform. Here, we propose the detailed functionality of each component considering unidirectional broadcasting of augmentation data. To meet the centimeter-level user positioning accuracy in maritime coverage, new reference stations were installed. Each reference station operates with a dual receiver and dual antenna to reduce the risk of malfunctioning, which can deteriorate the availability of the POINT service. The initial experimental results of a testbed from corrections generated from the testbed network, including newly installed reference stations, are presented. The results show that the horizontal and vertical accuracies satisfy 2.63 cm and 5.77 cm, respectively. For the purpose of (near) real-time broadcasting of POINT correction data, we designed a correction message format including satellite orbit, satellite clock, satellite signal bias, ionospheric delay, tropospheric delay, and coordinate transformation parameters. The (near) real-time experimental setup utilizing (near) real-time processing of testbed network data and the designed message format are proposed for future testing and verification of the system.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.88-88
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• 2017

• Journal of Positioning, Navigation, and Timing
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• v.10 no.3
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• pp.159-168
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• 2021

Precise Point Positioning-Real Time Kinematic (PPP-RTK) is an improved PPP method that provides the user receiver with satellite code and phase bias correction information in addition to the satellite orbit and clock, thus enabling single-receiver ambiguity resolution. Single station PPP-RTK concept is special case of PPP-RTK in that corrections are computed, instead of a network, by only one single GNSS receiver. This study is performed to experimentally verify the positioning accuracy performance of single baseline RTK level by a user who utilizes correction for a single station PPP-RTK using dual frequencies. As an experimental result, the horizontal and vertical 95% accuracy was 2.2 cm, 4.4 cm, respectively, which verify the same performance as the single baseline RTK.