摘要
本論文旨在研究低地球軌道衛星星座之設計，由於近年來科技的快速發展，各行各業中對於訊號低延遲的需求越來越高，同時對於頻寬的需求也與日俱增，而低地球軌道(Low-earth orbit)衛星恰巧可以滿足這些需求，但是低地球軌道衛星最大之缺點在於其覆蓋率會相較其他中、高地球軌道衛星小很多，為了解決這個致命性的問題，需要將許多低地球軌道衛星組合在一起形成星座的形式來改善單顆低地球軌道衛星覆蓋範圍不足所造成之問題。但目前大多數之文獻都針對全球覆蓋去進行低地球衛星星座之軌道設計，因此在經費受限或是任務需求有限制目標覆蓋範圍之情形下設計低地球軌道衛星星座將會是本研究之研究目標。 本研究主要以低地球軌道衛星星座之軌道設計為主研究目標，一開始先由較著名之 WalkerDelta Pattern 為設計之軌道類型，探討該類型衛星星座軌道對於全球覆蓋以及限定目標覆蓋範圍的比較，而本研究在低地球軌道衛星星座設計所使用之最佳化演算法為基因演算法，經由基因演算法將其適應性函數定義為整個低地球軌道衛星星座之覆蓋率，經過基因演算法後可得出最佳之 WalkerDelta Pattern 之軌道分布。接著根據限制之目標覆蓋範圍進行特化之低地球軌道衛星星座之設計，將兩者相互比較已獲得最符合任務需求之低軌道衛星星座。而經過基因演算法得出之參數套用到 MATLAB 及 System Tool Kit® (STK)中進行模擬和分析，隨後再將連續覆蓋等條件加入到設計目標其中以滿足不同之任務需求。
並列摘要
This thesis aims to study the design of low-Earth orbit satellite constellations. Due to rapid technological advancements in recent years, there is an increasing demand for low-latency signals and bandwidth in various industries. Low-Earth orbit (LEO) satellites can meet these demands, but their major disadvantage is that their coverage is much smaller compared to other medium and high-Earth orbit satellites. To solve this critical problem, many LEO satellites need to be combined into the form of constellations to improve the coverage of single LEO satellites. However, most literature currently focuses on global coverage for LEO satellite constellations. Therefore, designing LEO satellite constellations for limited target coverage under limited budget or mission requirements will be the research objective of this study. This research primarily focuses on the orbital design of low-Earth orbit satellite constellations. Initially, we will take the well-known WalkerDelta Pattern as the design for the orbital type, and examine its comparison for global coverage and limited target coverage. The optimization algorithm used in this research for the design of low-Earth orbit satellite constellations is the genetic algorithm, where its fitness function is defined as the overall coverage of the entire low-Earth orbit satellite constellation. By using the genetic algorithm, we can obtain the best orbital distribution of the WalkerDelta Pattern. Then, based on the limited target coverage, we will conduct specialized designs for low-Earth orbit satellite constellations and compare the two to obtain the low-Earth orbit satellite constellation that best meets the mission requirements. The parameters obtained from the genetic algorithm will be applied in MATLAB and System Tool Kit® (STK) for simulation and analysis. Additionally, continuous coverage and other conditions will be added to the design objectives to meet different mission requirements.