• 대한원격탐사학회지
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• 제21권3호
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• pp.173-188
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• 2005

The present study aims to derive and compare narrow and broad bandwidths of ocean color sensor’s algorithms for the study of monitoring highly dynamic coastal oceanic environmental parameters using high-resolution imagery acquired from Multi-spectral Camera (MSC) on KOMPSAT-2. These algorithms are derived based on a large data set of remote sensing reflectances ($R_{rs}$) generated by using numerical model that relates $b_b/(a + b_b)$ to $R_{rs}$ as functions of inherent optical properties, such as absorption and backscattering coefficients of six water components including water, phytoplankton (chl), dissolved organic matter (DOM), suspended sediment (SS) concentration, heterotropic organism (he) and an unknown component, possibly represented by bubbles or other particulates unrelated to the first five components. The modeled $R_{rs}$ spectra appear to be consistent with in-situ spectra collected from Korean waters. As Kompsat-2 MSC has similar spectral characteristics with Landsat-5 Thematic Mapper (TM), the model generated $R_{rs}$ values at 2 ㎚ interval are converted to the equivalent remote sensing reflectances at MSC and TM bands. The empirical relationships between the spectral ratios of modeled $R_{rs}$ and chlorophyll concentrations are established in order to derive algorithms for both TM and MSC. Similarly, algorithms are obtained by relating a single band reflectance (band 2) to the suspended sediment concentrations. These algorithms derived by taking into account the narrow and broad spectral bandwidths are compared and assessed. Findings suggest that there was less difference between the broad and narrow band relationships, and the determination coefficient $(r^2)$ for log-transformed data [ N = 500] was interestingly found to be $(r^2)$ = 0.90 for both TM and MSC. Similarly, the determination coefficient for log-transformed data [ N = 500] was 0.93 and 0.92 for TM and MSC respectively. The algorithms presented here are expected to make significant contribution to the enhanced understanding of coastal oceanic environmental parameters using Multi-spectral Camera.

• 항공우주기술
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• 제2권1호
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• pp.80-88
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• 2003

본 연구는 임무완성기간까지 다목적실용위성 2호기의 각 표면에 축적되는 입자오염량을 분석한 것이다. 이를 위하여 위성체의 조립 및 시험 기간 및 환경조건을 가정하였다. 본문에서 보여지는바와 같이 다목적실용위성2호의 조립 및 시험이 잘 관리되어지는 조건에서 수행된다면, 위성체의 각 표면에 축적되는 입자 오염량은 적정한 수준내로 관리 될 수 있다. 10,000 class의 발사장 환경을 기준으로 할때, AIT와 발사장에서의 조립 및 시험으로 인해 MSC 및 STA의 내구경에는 500PPM, 외부 표면에는 20000PPM, 위성체의 수평면에는 14000PPM, 수직면에는 1400PPM, radiator에는 1000PPM 및 solar array에는 300PPM의 입자오염량이 축적될 것으로 예상된다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.101-101
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• 2000

MSC(Multispectral Camera), which will be a unique payload on KOMPSAT-II, is designed to collect panchromatic and multi-spectral imagery with a ground sample distance of 1m and a swath width of 15km at 685km altitude in sun-synchronous orbit. The instrument is designed to have an orbit operation duty cycle of 20% over the mission life time of 3 years. MSC electronics consists of three main subsystems; PMU(Payload Management Unit), CEU(Camera Electronics Unit) and PDTS(Payload Data Transmission Subsystem). PMU performs all the interface between spacecraft and MSC, and manages all the other subsystems by sending commands to them and receiving telemetry from them with software protocol through RS-422 interface. CEU controls FPA(Focal Plane Assembly) which contains TDI(Timc Delay Integration) CCD(Charge Coupled Device) and its clock drivers. PMU provides a Master Clock to synchronize panchromatic and multispectral camera. PDTS performs compression, storage and encryption of image data and transmits them to the ground station through x-band.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 춘계학술대회 논문집
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• pp.305-307
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• 2007

KOMPSAT-2(K-2) 의 MSC 는 CCD pixel 별 band 별 특성, 감도 및 시간에 따른 변화, CCD Geometry 등에 의해 왜곡 현상이 일어나며 위성 발사 전에 실험실에서의 충분한 실험과 Calibration 작업 을 통해 얻어진 값들을 사용하여 Image Restoration, 상대 복사 보정, 절대 복사 보정 등의 작업들을 거쳐서 왜곡 현상을 보정하게 된다. 그 중 복사 보정에 해당하는 NUC(NonUniformity Correction)은 MSC 각각의 픽셀들이 상이한 특성을 나타내는 것을 균일한 이미지로 보정하는 작업으로 무엇보다 우선시 되는 검보정 작업이다. K-2 NUC table 생성에는 시스템 특성상 몇 가지 사항을 고려 하여 위성에 upload 하는 high frequency NUC(HF NUC)과 지상국에서 처리할 수 있는 low frequency NUC(LF NUC)으로 구분하여 알고리즘을 생성하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.489-492
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• 2005

As a former level of MSC(Multi Spectral Camera) telescope of the KOMPSA T2satellite, the several performance tests of EOS(Electro Optical Subsystem) were performed in the EOS level. By these tests, not only the design requirement of payload can be verified but also the test result can be the important criterion to estimate the performance of payload in the launch and space orbit environment. The EOS Geometric Mapping test is to verify the accuracy of the alignment & assembly on the Subsystem of the MSC by measurement like these; LOS(Line of Sight), LOD(Line of Detector), Band to Band Registration, Optical Distortion and Reference Cube. This paper describes the test results and the analysis for the EOS Geometric Mapping.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1096-1098
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• 2003

SBC(Single Board Computer) is being developed for MSC(Multi-Spectral Camera) on KOMPSAT-2(Korea Multi-Purpose Satellite). SBC controls all the units of MSC system and gets commands and sends telemetry to and from spacecraft bus via 1553 communication channel. Due to the fact that SBC does very important roles for MSC system operation and SBC operates with 100% duty cycle, SBC is designed to have high reliability. SBC which has Intel 80486 as a main processor includes eight serial communication channels, one mil-std-1553 interface channel and several discrete interfaces. SBC incorporates 2Mbyte radiation hardened SRAM(Static Random Access Memory) and 1Mbyte flash memory. There are also PIC(Programmable Interrupt Controller), counter, WDT(Watch Dog Timer) in the SBC. In this paper, the design result of the SBC is presented.

• 한국위성정보통신학회논문지
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• 제1권2호
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• pp.76-82
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• 2006

한국전자통신연구원이 개발하여 항공우주연구원의 관제소에 설치한 아리랑2호 위성 관제시스템은 지난 7월 28일 발사된 아리랑2호 위성의 운용에 사용되고 있다. 아리랑2호 관제시스템의 대표적인 기능으로는 원격측정데이터 수신 및 처리, 원격명령 생성 및 송신, 위성 추적 및 거리측정, 궤도 예측 및 결정, 위성자세 조정계획, 그리고 위성 시뮬레이션 등이 있다. 아리랑2호 위성은 아리랑1호 위성의 임무를 이어받아 수행하며, MSC (Multi Spectral Camera) 및 정밀궤도결정, 정밀자세결정 등을 통해 아리랑1호에 비해 훨씬 향상된 해상도의 사진을 제공하는 성능을 가지고 있다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 춘계학술대회 논문집
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• pp.20-24
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• 2007

센서의 광학 해상력에 따라 센서에 도달하는 에너지의 앙은 영상의 화소값으로 변환되므로，이 관계는 위성 영상의 정량적인 광학적 특성을 이해하기 위한 바탕이 되며，영상의 질을 유지하기 위한 척도가 되기도 한다. 위성영상의 광학적 특성은 ON 값 을 실제 지표물의 반사에너지 값인 Radiance와 Reflectance로 의 변환을 통하여 추정할 수 있으며，이러한 과정을 절대복사보정(Absolute Radiometric Calibration) 이라고 한다. 절대복사보정 과정에서 센서에 도달하는 태양 에너지의 양을 추정하기 위하여 복사전달모델이 사용된다. 태양 에너지가 대기를 통과함에 따라 여러 가지 상호 작용이 일어나게 되므로 복사 전달모델을 사용하기 위해서는 다양한 입력 변수가 필요하게 된다. 이러한 입력 변수로는 지표물의 반사율， 대기자료，그리고 센서의 특성 등이 포함되며， 이 연구에서는 KOMPSAT-2 위성의 MSC 영상의 절대복사보정 과정에서 복사전달모델의 결과에 영향을 미치는 입력 변수의 특성을 살펴보고자 한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.448-451
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• 2004

MSC (Multi-Spectral Camera) system is an electro-optical camera system which is being developed to be installed on KOMPSAT-2 satellite. High resolution image data from MSC system will be transmitted to the ground-station through x-band antenna called APS (Antenna Pointing System). APS is a directional antenna which will point to the receiving antenna at ground station while the satellite is passing over it. The APS needs to be controlled accurately to provide the reliable communication with big RF link margin. The APS is controlled by ATS (Antenna Tracking Software) which is included in the MSC software. ATS uses the closed loop control algorithm which will use TPF (Tracking Parameter File) as an input for antenna position, and will use two resolve readings from APS as a feedback. ATS has been developed and verified using APS QM (Qualification Model) and all the control parameters for ATS have been tested and verified. Various kinds of maximum, nominal and realistic dynamics for the APS movement have been simulated and verified. In this paper, closed loop servo control algorithm and obtained APS position error from the verification test with APS QM will be presented in detail

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.196-200
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• 2004

The purpose of this study is to examine the image­based atmospheric correction models using the data from Landsat Enhanced Thermal Mapper Plus (ETM+) that have quite similar spectral characteristics to the forthcoming Korea Multi-Purpose SATellite (KOMPSAT)-2 Multi-Spectral Camera (MSC), and the in-situ measured surface reflectance data during satellite overflight. The main advantage of this type of correction is that it does not require in-situ measurements during each satellite overflight. While substantial differences are present between Top-Of-the Atmosphere (TOA) reflectance and in-situ measurements, the results showed that Case 1 based on COST model gives most accurate results among three cases. The accuracy of Case 2 is very close to Case 1 and its values are smaller than in-situ data. No notable features appear between some bands in the Case 3 and in-situ data. It is expected from this study that if the current methods are applied to the IKONOS high resolution data, we will be able to develop the suitable atmospheric correction methods for MSC data.