In this study, we describe an analytical process for designing a low Earth orbit constellation for discontinuous regional coverage, to be used for a surveillance and reconnaissance space mission. The objective of this study was to configure a satellite constellation that targeted multiple areas near the Korean Peninsula. The constellation design forms part of a discontinuous regional coverage problem with a minimum revisit time. We first introduced an optimal inclination search algorithm to calculate the orbital inclination that maximizes the geometrical coverage of single or multiple ground targets. The common ground track (CGT) constellation pattern with a repeating period of one nodal day was then used to construct the rest of the orbital elements of the constellation. Combining these results, we present an analytical design process that users can directly apply to their own situation. For Seoul, for example, 39.0° was determined as the optimal orbital inclination, and the maximum and average revisit times were 58.1 min and 27.9 min for a 20-satellite constellation, and 42.5 min and 19.7 min for a 30-satellite CGT constellation, respectively. This study also compares the revisit times of the proposed method with those of a traditional Walker-Delta constellation under three inclination conditions: optimal inclination, restricted inclination by launch trajectories from the Korean Peninsula, and inclination for the sun-synchronous orbit. A comparison showed that the CGT constellation had the shortest revisit times with a non-optimal inclination condition. The results of this analysis can serve as a reference for determining the appropriate constellation pattern for a given inclination condition.

1. INTRODUCTION
2. Optimal inclination for single ormultiple target regional co verage
    2.1 2D coverage map
    2.2 Coverage map with optimal inclination
3. Common ground track (CGT)con stellation design
4. Results and Discussion
    4.1 Revisit times of CGT constellation with optimalinclination
    4.2 Comparisons between Common ground track (CGT)constellation and Walker-Delta constellation
5. Conclusion
ACKNOWLEDGMENTS
REFERENCES

• Jinyoung Shin(Astrodynamics and Control Laboratory, Department of Astronomy, Yonsei University)
• Sang-Young Park(Astrodynamics and Control Laboratory, Department of Astronomy, Yonsei University) Corresponding author
• Jihae Son(Hanwha Systems Co., Ltd)
• Sung-Chan Song(Hanwha Systems Co., Ltd)