• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.561-563
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• 2005

From the IF (Intermediated Frequency) loop-back test, BER (Bit Error Rate) degradation of processed data, HRIT (High Rate Information Transmission), is estimated by proposed measurement configuration. The specific parameters, likely data rate, FEC (Forward Error Correction), and modulation method, are based on the outcomes of SRR (System Requirements Review) which was held on 13-14 June 2005, in Toulouse. The proposed measurement procedure is that combined 70MHz modulated signal and noise is connected to the spectrum analyzer and receiver. The former measures the C/No (Carrier to Noise density ratio) and the latter estimates BER of FEC decoded data. Implementation loss can be obtained by subtracting measured BER from calculated BER which is also subtracted data rate from measured C/No. This test procedure is very simple and can be applied to assess the implementation loss of dedicated receiver for HRIT in the future.

• Proceedings of the KSRS Conference
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• v.1
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• pp.64-66
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• 2006

DATS will connect with IMPS and LHGS to perform the reception of sensor data and the transmission of user's meteorological data, LRIT and HRIT. MODEM/BB will perform the de-commutation of received sensor data as MI and GOCI raw data according to VCID before sending them to MI and GOCI IMPS, respectively. Especially, MODEM/BB in SOC needs to be connected to six clients that consist of the primary and backup IMPS of MSC, KOSC and SOC. On the other hand, LRIT and HRIT delivered from LHGS are encoded as VITERBI and modulated by MODEM/BB. Considering sensor data transmitted from COMS, the assumed format and size of CADU are described in this paper. Finally, results related to the status of received LRIT and HRIT by frame synchronizer in user station are also described.

• Current Industrial and Technological Trends in Aerospace
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• v.6 no.1
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• pp.105-115
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• 2008

The organization for satellite operation team is mainly based on the number of satellites to be controlled, operator's workload of payload operation support and the degree of automation of the operation system. Although the structure and its functionality of satellite operation organization are a little different according to the complexity of the operation, most satellite control centers have adapted the similar architecture for single or multiple satellite support. KARI Satellite Operation Center(KSOC) has started its simple mission operations since the launch of KOMPSAT-1(21st Dec. 1999) and has been evolving into multiple mission operations for various satellites such as KOMPSAT-2, KOMPSAT-3, KOMPSAT-5 and COMS(Communication Ocean Meteorological Satellite). This paper presents the appropriate direction of future deployment for KSOC by comparing the current status with the recommendation of the advanced satellite operation organization and analyzing their experiences in order to propose the better solution for efficient and safe satellite operations.

• Journal of Astronomy and Space Sciences
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• v.17 no.2
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• pp.285-294
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• 2000

The post-launch mission analysis of the KOMPSAT-1 spacecraft was carried out. The injection accuracy of the Taurus launch vehicle was analyzed by comparison of the target and the realized orbit parameters. The tracking station contact analysis was also performed based on the state vectors applied at the day of launch. The offset angles between the predicted orbit and realized orbit were calculated for various tracking stations. The injection orbit parameters of the KOMPSAT-1 were analyzed for the possible options in Launch and Early Orbit Phase(LEOP) operations. Variations of the Local Time of Ascending Node(LTAN) were also obtained.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.390-393
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• 2006

본 논문에서는 현재 개발 중인 통신해양기상위성(COMS : Communication, Ocean and Meteorological Satellite)의 데이터를 처리하는 영상 데이터 전처리 시스템 (IMPS, IMage Preprocessing Subsystem)의 설계 과정과 예비설계 결과를 설명한다.

• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.76-82
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• 2006

The Mission Control System for KOMPSAT-2 was developed by ETRI and is being operated at Satellite Control Center at KARI to monitor and control KOMPSAT-2 (KOrea Multi-Purpose Satellite) which was launched in July 28th, 2006. MCE provides the functions such as telemetry reception and processing, telecommand generation and transmission, satellite tracking and ranging, orbit prediction and determination, attitude maneuver planning, satellite simulation, etc. KOMPSAT-2 is the successor of KOMPSAT-1 which is an earth-observation satellite. KOMPSAT-2 has higher resolution image taking ability due to MSC (Multi Spectral Camera) payload in the satellite and precise orbit and attitude determination by Mission Control System. It can produce one meter resolution image compared to six meter resolution image by KOMPSAT-1.

• ETRI Journal
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• v.21 no.3
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• pp.29-40
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• 1999

The Mission Analysis and Planning System (MAPS) has been developed for a low earth orbiting remote sensing satellite, Korea Multipurpose Satellite-I (KOMPSAT-I), to monitor and control the orbit and the attitude as well as to generate mission timelines and command plans. The MAPS has been designed using a top-down approach and modular programming method to ensure flexibility in modification and expansion of the system. Furthermore, a graphical user interface has been adopted to ensure friendliness. Design, Implementation, and testing of the KOMPSAT is discussed in this paper.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.195.1-195.1
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• 2012

Korea Aerospace Research Institute has developed an earth observation satellite whose primary mission objective is to provide high resolution electro optical earth images for Geographical Information Systems (GIS) establishment and the applications for environmental, agriculture and ocean monitoring. It was successfully launched into its mission orbit by using a commercial launch vehicle on 18th of May, 2012. This paper describes a series of launch activity at the launch site including its transportation to the launch site. Before conducting the launch site operation, satellite operation plane was prepared. Combining the satellite operation plan and launch vehicle activities, an integrated launch site operation plan and schedule have been drawn up. After arrival of the spacecraft at the launch site, post-ship check out has been conducted. And then it was fuel loaded and integrated with launch vehicle hardware. After completion of final electrical check out, count down procedure was executed. on 18th of May, it was launched into the space and was separated from the launch vehicle as planned. About 3 months of early operation and calibration/validation, now the satellite is conducting its normal mission.

• Aerospace Engineering and Technology
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• v.13 no.2
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• pp.142-149
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• 2014

After launch of Low Earth Orbit(LEO) satellite, Initial Activation Checkout(IAC) and Calibration and Validation(Cal & Val) procedure are performed prior to enter normal operation phase. During normal operation phase, most of the time is allocated for mission operation except following up measures to anomaly and orbit maintenance. Since mission operation capability is key indicator for success of LEO satellite program and consistent with promotion purpose of LEO satellite program, reliability should be ensured by conducting through test. In order to ensure reliability by examining the role of LEO satellite and ground station during ground test phase, realistic test scenario that is similar to actual operation conditions should be created, and test that aims to verify full mission cycle should be performed by transmitting created command and receiving image and telemetry data. This paper describes the test design and result. Consideration items for test design are described in detail and result of designed test items are summarized.

• Aerospace Engineering and Technology
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• v.9 no.2
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• pp.176-184
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• 2010

The power simulator for a LEO satellite is a useful tool to analyze mission validity and energy balance for various mission scenarios by estimating power generation, power consumption, depth of discharge, bus voltage, charging/discharging current, etc. In this paper, it is described the calculation algorithm of the solar array (SA) power, the satellite load power and the battery modeling method to develop a satellite power simulation. To simulate the SA power generation, three different operation modes (DET, MPPT, CV) of SAR (Solar Array Regulator) are considered with a SA model. The satellite load power is estimated using the satellite unit power database, the unit on/off configuration at some satellite operation modes. The bus voltage and battery charging/discharging current at the specific DoD (Depth of Discharge) are calculated based on the battery characteristics. By this satellite power simulator, it can be conveniently analyzed the energy balance and the validity of a planned mission of a LEO satellite.