In this paper we study the potential application of quantum search algorithm to
the spacecraft navigation. Traditionally the attitude and orbit determination can
be achieved by recognizing the relative position/attitude to the background stars
using sun sensors, earth limb sensors, or star trackers. Due to the massive celestial
database, however, star pattern recognition is a complicated and power consuming
job. We propose a new method of attitude and orbit determinations by applying
the quantum search algorithm to the search of a specific star or star pattern. The
quantum search algorithm, proposed by Grover in 1996, could search the specific
data out of an unstructured database containing a number of N data in only O( yiN)
steps, while it would take conventional computers to look through an average of N /2
steps. As a result, by taking the advantage of matching a particular star in a vast
celestial database in very limited steps, we could acquire the position/attitude of the
spacecraft rapidly for navigation, guidance and control. 本文主要探討「量子搜尋法」來進行未來太空船的導航的可能性。傳統上，姿
態跟軌道決定主要利用太陽感測器、地球感測器、或是尋星器來進行背景星空
比對，再求出其相對位置或姿態。然而，由於星空資料庫太龐大了，要進行星
座辨視是很複雜且耗能的。本文提出可利用量子搜尋法來字成此一任務。Grover
於1996年提出的量子搜尋法，能在O( √N可)個步驟內，便能性N筆雜亂無章的資料
中找出特定資料。對於傳統搜尋法而言，平均需要Nj/2 步才能找到。因此，利用
量子搜尋法強大的搜尋功能，我們可以在非常少的步驟之內，便從龐大的星空資
料庫中找出我們需要的星體資訊。並可將之用於計算所需的位置及姿態訊息，導
引及控制太空船飛行。
