A NEW LOW COST DIRECT ARCHIVING AND PREPROCESSING SYSTEM FOR KITSAT-3 IMAGE DATA 
Taejung Kim*, Impyeong Lee* and Soon Dal Choi** 
Research Fellow*, Director** 
Satellite Technology Research Center 
Korea Advanced Institute of Science and Technology 
373-1, Kusung-Dong, Yusung-Gu 
Taejon, Korea 
email: tjkim @krsc.kaist.ac.kr, iplee @ krsc.kaist.ac.kr 
Commission I, Working Group 1/6 
KEY WORDS: Archiving, Hardware, Satellite 
ABSTRACT 
This paper describe the development of a low cost direct archiving and preprocessing system. The system will be used 
for a small satellite called KITSAT-3. Among many advantages of the use of small satellites, the feasibility of the 
development of a simple and low cost ground receiving station is one of the most meaningful as far as the ground 
segments concerned. The moderate speed of small satellites makes it possible to replace expensive dedicated 
hardware by cheap commercial Personal Computers and dedicated software. 
In order to develop a low cost direct archiving system, a PC interface card was developed. This card converts incoming 
stream into parallel words and store them into the hard disk of a PC. For frame synchronization process, a dedicated 
software was developed. The techniques used for this development are not very complicated, which proves the 
advantage of the use of small satellites. Although the system developed here has the fundamental limitation of the 
speed of incoming data stream, the system upgrade should be done also without great difficulties with the fast 
advancing PC technologies. 
1. INTRODUCTION satellites can reduce the size and complexity of the 
ground receiving station significantly. With this, the 
A earth imaging satellite takes pictures of the earth development of low cost receiving station is very feasible. 
surface and usually stores a large amount of data 
onboard recorder. When the communication link between 
the satellite and the ground receiving station is set up, the In this paper, the development of a low cost direct 
image data stored onboard are transmitted to the archiving and preprocessing system will be described. 
receiving antenna of the ground station. After reception, This system will be used for a small satellite called 
appropriate operations should be carried out to restore KITSAT-3. The KITSAT-3 is the third satellite of the 
proper image data and these image data should be KITSAT series manufactured by Satellite Technology 
stored in real-time. Research Center of KAIST, Korea. As this satellite has a 
down-link speed of 3Mbps, the conventional (expensive) 
The development of such ground receiving system is dedicated hardware can be replaced by a commercial 
often very complex and difficult as image data are computer hardware. The cost effectiveness can be 
usually very bulky and the data rate from the satellite to achieved by avoiding the dedicated hardware and, 
the ground station is very high. To handle this high speed instead, developing dedicated software. 
data, dedicated hardware such as High Density Tape 
Recorder (HDTR) and Frame Synchronizer have been This paper will start with general description of the 
developed and used for commercial remote sensing KITSAT-3 ground receiving system. Section 3 will discuss 
satellites. However, these are very expensive devices and about the development and the implementation of this 
difficult to control. system. In particular, implementation will concentrate on 
the development of a direct archiving recorder and frame 
The idea of the use of small satellites for earth synchronization software. Some conclusions are included 
observation is becoming more and more popular as this in section 4. 
gives several merits over the use conventional large 
remote sensing satellites: small satellites are easier and 
cheaper to manufacture; small satellites are less risky; 
small satellites can accommodate fast changing user's 
need better, and etc. Moreover, the use of small 
84 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B1. Vienna 1996 
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