• Title/Summary/Keyword: Satellite Laser Ranging (SLR)

Search Result 49, Processing Time 0.03 seconds

PRECISE OR81T DETERMINATION OF GPS-36 SATELLITE USING SATELLITE LASER RANGING (SLR을 이용한 GPS-36 위성의 정밀 궤도 결정)

  • 임형철;박관동;박필호;박종욱;조정호
    • Journal of Astronomy and Space Sciences
    • /
    • v.19 no.4
    • /
    • pp.385-394
    • /
    • 2002
  • Satellite laser ranging is a technique for precisely measuring the range between a laser station and a satellite that is equipped with retro-reflectors. SLR technique was first used for Beacon-B satellite in 1964 with the ranging accuracy of meter level. Now the single shot have centimeter level accuracy and the normal point have mm level in ranging. In this study we developed the algorithm for precise orbit determination using SLR data and performed the orbit determination of GPS-36 satellite using the algorithm. RMS of the estimated orbit was 74cm when compared with IGS precise orbit. It is known that RMS of SLR measurement residual is below 55mm. But we were able to achieve 44mm RMS of residual throughout this study.

Design and Development of High-Repetition-Rate Satellite Laser Ranging System

  • Choi, Eun-Jung;Bang, Seong-Cheol;Sung, Ki-Pyoung;Lim, Hyung-Chul;Jung, Chan-Gyu;Kim, In-Yeung;Choi, Jae-Seung
    • Journal of Astronomy and Space Sciences
    • /
    • v.32 no.3
    • /
    • pp.209-219
    • /
    • 2015
  • The Accurate Ranging System for Geodetic Observation - Mobile (ARGO-M) was successfully developed as the first Korean mobile Satellite Laser Ranging (SLR) system in 2012, and has joined in the International Laser Ranging Service (ILRS) tracking network, DAEdeoK (DAEK) station. The DAEK SLR station was approved as a validated station in April 2014, through the ILRS station "data validation" process. The ARGO-M system is designed to enable 2 kHz laser ranging with millimeter-level precision for geodetic, remote sensing, navigation, and experimental satellites equipped with Laser Retro-reflector Arrays (LRAs). In this paper, we present the design and development of a next generation high-repetition-rate SLR system for ARGO-M. The laser ranging rate up to 10 kHz is becoming an important issue in the SLR community to improve ranging precision. To implement high-repetition-rate SLR system, the High-repetition-rate SLR operation system (HSLR-10) was designed and developed using ARGO-M Range Gate Generator (A-RGG), so as to enable laser ranging from 50 Hz to 10 kHz. HSLR-10 includes both hardware controlling software and data post-processing software. This paper shows the design and development of key technologies of high-repetition-rate SLR system. The developed system was tested successfully at DAEK station and then moved to Sejong station, a new Korean SLR station, on July 1, 2015. HSLR-10 will begin normal operations at Sejong station in the near future.

Development of Operation Software for High Repetition rate Satellite Laser Ranging (고반복율 인공위성 레이저추적을 위한 운영 소프트웨어 개발)

  • Sung, Ki-Pyoung;Choi, Eun-Jung;Lim, Hyung-Chul;Jung, Chan-Gyu;Kim, In-Yeong;Choi, Jae-Seung
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.44 no.12
    • /
    • pp.1103-1111
    • /
    • 2016
  • Korea Astronomy and Space Science Institute (KASI) has been operating SLR (Satellite Laser Ranging) system with 2kHz repetition rate for satellite precise orbit and spin determination as well as space geodesy. But the SLR system was improved to be capable of laser ranging with high repetition rate, up to 10kHz by developing new operation software and novel range gate generator, called HSLR-10. The HSLR-10 will contribute to the accurate spin rate determination of geodetic satellites and geodetic research due to its largest repetition rate in the world. In this study, the development methodology and configuration of operation software are addressed, and its validation results are also presented.

Validation of Geostationary Earth Orbit Satellite Ephemeris Generated from Satellite Laser Ranging

  • Oh, Hyungjik;Park, Eunseo;Lim, Hyung-Chul;Lee, Sang-Ryool;Choi, Jae-Dong;Park, Chandeok
    • Journal of Astronomy and Space Sciences
    • /
    • v.35 no.4
    • /
    • pp.227-233
    • /
    • 2018
  • This study presents the generation and accuracy assessment of predicted orbital ephemeris based on satellite laser ranging (SLR) for geostationary Earth orbit (GEO) satellites. Two GEO satellites are considered: GEO-Korea Multi-Purpose Satellite (KOMPSAT)-2B (GK-2B) for simulational validation and Compass-G1 for real-world quality assessment. SLR-based orbit determination (OD) is proactively performed to generate orbital ephemeris. The length and the gap of the predicted orbital ephemeris were set by considering the consolidated prediction format (CPF). The resultant predicted ephemeris of GK-2B is directly compared with a pre-specified true orbit to show 17.461 m and 23.978 m, in 3D root-mean-square (RMS) position error and maximum position error for one day, respectively. The predicted ephemeris of Compass-G1 is overlapped with the Global Navigation Satellite System (GNSS) final orbit from the GeoForschungsZentrum (GFZ) analysis center (AC) to yield 36.760 m in 3D RMS position differences. It is also compared with the CPF orbit from the International Laser Ranging Service (ILRS) to present 109.888 m in 3D RMS position differences. These results imply that SLR-based orbital ephemeris can be an alternative candidate for improving the accuracy of commonly used radar-based orbital ephemeris for GEO satellites.

Preliminary Perfomances Anlaysis of 1.5-m Scale Multi-Purpose Laser Ranging System (1.5m급 다목적형 레이저 추적 시스템 예비 성능 분석)

  • Son, Seok-Hyeon;Lim, Jae-Sung
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.49 no.9
    • /
    • pp.771-780
    • /
    • 2021
  • The space Debris laser ranging system is called to be a definite type of satellite laser ranging system that measures the distance to satellites. It is a system that performs POD (Precise Orbit Determination) by measuring time of flight by firing a laser. Distance precision can be measured in mm-level units, and it is the most precise system among existing systems. Currently, KASI has built SLR in Sejong and Geochang, and utilized SLR data to verify the precise orbits of the STSAT-2C and KOMASAT-5. In recent years, due to the fall or collision of space debris, its satellites have been threatened, and in terms of security, laser tracking of space objects is receiving great interest in order to protect their own space assets and protect the safety of the people. In this paper, a 1.5m-class main mirror was applied for the system design of a multipurpose laser tracking system that considers satellite laser ranging and space object laser tracking. System preliminary performance analysis was performed based on Link Budget analysis considering specifications of major components.

Satellite Laser Ranging System at Geochang Station

  • Lim, Hyung-Chul;Sung, Ki-Pyoung;Yu, Sung-Yeol;Choi, Mansoo;Park, Eunseo;Park, Jong-Uk;Choi, Chul-Sung;Kim, Simon
    • Journal of Astronomy and Space Sciences
    • /
    • v.35 no.4
    • /
    • pp.253-261
    • /
    • 2018
  • Korea Astronomy and Space Science Institute (KASI) has been developing the space optical and laser tracking (SOLT) system for space geodesy, space situational awareness, and Korean space missions. The SOLT system comprises satellite laser ranging (SLR), adaptive optics (AO), and debris laser tracking (DLT) systems, which share numerous subsystems, such as an optical telescope and tracking mount. It is designed to be capable of laser ranging up to geosynchronous Earth orbit satellites with a laser retro-reflector array, space objects imaging brighter than magnitude 10, and laser tracking low Earth orbit space debris of uncooperative targets. For the realization of multiple functions in a novel configuration, the SOLT system employs a switching mirror that is installed inside the telescope pedestal and feeds the beam path to each system. The SLR and AO systems have already been established at the Geochang station, whereas the DLT system is currently under development and the AO system is being prepared for testing. In this study, the design and development of the SOLT system are addressed and the SLR data quality is evaluated compared to the International Laser Ranging Service (ILRS) tracking stations in terms of single-shot ranging precision. The analysis results indicate that the SLR system has a good ranging performance, to a few millimeters precision. Therefore, it is expected that the SLR system will not only play an important role as a member of the ILRS tracking network, but also contribute to future Korean space missions.

GEO-KOMPSAT-2 Laser Ranging Time Slot Analysis (정지궤도복합위성 레이저 레인징 가능 시간대 해석)

  • Park, Bongkyu;Choi, Jaedong;Lee, Sang-Ryool
    • Journal of Aerospace System Engineering
    • /
    • v.12 no.1
    • /
    • pp.10-16
    • /
    • 2018
  • In 2018 and 2019, GEO-KOMPSAT-2A and GEO-KOMPSAT-2B will be launched in order to succeed the COMS mission. The two satellites will be collocated in $128.25{\pm}0.05$ degrees East. For precise ranging and orbit determination, the GEO-KOMPSAT-2B will be equipped with LRA (Laser Retroreflector Assembly) and SLR (Satellite Laser Ranging) systems will be utilized. This systems are located in Geochang. In this case, the laser beam emitted from the SLR station can cause problems in terms of safety of optical payloads and image quality. As a solution of this possibility, the laser ranging will be done during the night time when the shutters of the optical payloads remain closed. Still, the optical payload of the GEO-KOMPSAT-2A is not safe from the laser beam because its optical payload shall continue its mission for 24 hours a day. In order to handle this problem, the laser ranging shall be limited to time slots when the angular distance between two satellites observed from the Geochang SLR station is large enough. In this paper, through orbit simulations, the characteristics of variation of the angular distance between the two satellites is analyzed to figure out the time slots when laser ranging is allowed.

The Design Concept of the First Mobile Satellite Laser Ranging System (ARGO-M) in Korea

  • Jo, Jung-Hyun;Park, In-Kwan;Lim, Hyung-Chul;Seo, Yoon-Kyoung;Yim, Hong-Seo;Lee, Jin-Young;Bang, Seung-Cheol;Nah, Ja-Kyoung;Kim, Kwang-Dong;Jang, Jeong-Gyun;Jang, Bi-Ho;Park, Jang-Hyun;Park, Jong-Uk
    • Journal of Astronomy and Space Sciences
    • /
    • v.28 no.1
    • /
    • pp.93-102
    • /
    • 2011
  • Korea Astronomy and Space Science Institute (KASI) launched the development project of two satellite laser ranging (SLR) systems in early 2008 after the government fund approval of the SLR systems in 2007. One mobile SLR system and one permanent SLR station will be developed with the completion of the project. The main objectives of these systems will be focused on the Space Geodetic researches. A system requirement review was held in the second half of the same year. Through the following system design review meeting and other design reviews, many unsolved technical and engineering issues would be discussed and resolved. However, the design of the mobile SLR system is a corner stone of whole project. The noticeable characteristics of Korea's first SLR system are 1) use of light weight main mirror, 2) design of compact optical assembly, 3) use of KHz laser pulse, 4) use of commercial laser generator, 5) remote operation capability, 6) automatic tracking, 7) state of art operation system, etc. In this paper, the major user requirement and pre-defined specification are presented and discussed.

SLR 데이터를 사용하기 위한 효율적인 정밀궤도결정 전략

  • Kim, Yeong-Rok;Park, Sang-Yeong;Choe, Gyu-Hong
    • Bulletin of the Korean Space Science Society
    • /
    • 2009.10a
    • /
    • pp.27.2-27.2
    • /
    • 2009
  • SLR (Satellite Laser Ranging) 데이터의 높은 거리측정 정밀도는 위성 추적 시스템의 검증 및 보정, 위성의 정밀궤도결정, 지구와 관련된 물리 상수 및 모델 검증, 우주파편과 같은 우주물체의 추적 및 감시 등에 활용이 가능하다. 특히 위성의 정밀궤도결정에 SLR 데이터를 활용하는 것은 고정밀 지구관측 위성 및 독자적인 항법 시스템 운영에 필수적인 부분이다. SLR 시스템은 위성 관측 가능 시간 및 지역이 한정되어 있기 때문에 정밀궤도 결정에 활용하는 것이 쉽지 않다. 따라서 이 연구에서는 SLR 데이터를 사용하기 위한 효율적인 정밀궤도결정 전략에 대해서 알아보았다. 동역학 및 관측 모델, 지상국의 개수, 초기 궤도 오차, 필터링 방법, 고도각에 따른 관측 데이터 선택 등의 기준을 선정하고 각각의 경우에 대해 정밀궤도결정을 수행하고 결과를 분석하였다. 정밀궤도결정 테스트를 위해서는 YLPODS (Yonsei Laser-ranging Precision Orbit Determination System)과 SLR정규점 (Normal Point) 데이터를 사용하였다. 이를 통해서 SLR 데이터를 사용하기 위한 효율적인 정밀궤도결정 전략에 대해 고찰해보았다.

  • PDF