時至今日全球定位系統(Global Positioning System)已被廣泛的應用於民間導航定位，以全球定位系統為基礎的姿態決定亦是如此。其運用載具上所安裝之天線配置而定義的基線向量於空間中的改變來判斷載具姿態。實際應用此方法時，可以利用一次差分載波相位觀測量以及因為衛星在空間中幾何分布所得到幾何矩陣決定，然而即便是在估算線路誤差以及整數周波不確定數的數值後，觀測量方面仍然會受到環境的多路徑效應及雜訊的影響影響。這些誤差造成載具的估測姿態偏離實際載具的姿態，在正常的情況下透過對系統的了解，可以畫出系統觀測量對姿態估測誤差的線性關係，如此再配合假完整性風險(Integrity Risk)機率和連續性(Continuity)的機率將可以決定一個估測誤差的保護值，即保護極限(Protection Level)。此保護極限提供在既有觀測量情況，滿足上述機率條件下的最大可能的姿態估測誤差，未來此值可以用來與依照不同任務需求階段而定義的載具姿態警告極限(Alert Limit)做比較，用以判斷系統的可用性(Availability)。以往姿態估測保護極限由最小平方方法求得，然而此方法缺少錯誤偵測與排除機制，當有錯誤的觀測量存在時，此觀測量將無法被排除進而導致系統的可用性下降。 因此本論文使用採用多重假設分隔解方法，利用其演算中內涵的錯誤偵測與排除機制來彌補這樣的缺失。首先依據可使用的觀測量數目假設可能的系統錯誤模式，接著依據衛星錯誤發生的機率決定可以被排除而不需要監控的系統錯誤狀況，其後再將完整性風險預算機率分配給不同的錯誤模式。同理，將連續性的機率預算平均分配給各個可能的錯誤模式。 接著由於系統全部之致命性誤導資訊(Hazardously Misleading Information)的機率為在各個錯誤模式下的致命性誤導資訊的機率之總和。由此關係可以列出一個包含各種錯誤模式下以保護極限為未知數的方程式，解算此方程式後求得一個滿足完整性以及連續性要求且較為實際的保護極限值。最後為了顯示多重假設分隔解方法的錯誤偵測與排除機制，論文實際進行動態實驗加以驗證。實驗結果顯示無論在載具處於靜態或動態姿態運動，多重假設分隔解方法計算之保護極限都能完整的包圍住估測誤差，並且在刻意加入錯誤的實驗中可以看出，多重假設分隔解方法能夠正確的偵測錯誤並將之排除。

Nowadays Global Positioning System (GPS) has been widely used in different navigation applications. One of these important applications is GPS attitude determination. Given the antenna configurations the baselines can be defined and then the attitude is determined by the change of baseline on the coordinate. Practically it takes single difference carrier phase as measurements and decides a geometric matrix according to satellite distribution on the sky to conduct attitude estimation. However since there are multipath and noise after conducting line bias and integer ambiguity resolutions, the attitude estimation will deviate from the true vehicle attitude. Under normal condition with prior inspection for algorithm the linear relation between measurement residual and attitude estimation error can be derived. Further given the probability of integrity risk and the probability of continuity requirement, the protection level is determined. This protection level can be further compared with the alert limit which is decided according to different application requirements. Previously the protection level for attitude determination is calculated by least squared method, this kind of integrity system is lack of a mechanism to detect and exclude faulty measurement. As a result the Multiple Hypothesis Solution Separation (MHSS) method is therefore suggested in this thesis to add this feature. First the nominal bias and standard deviation of the measurements are decided and what kinds of fault hypothesis should not be taken into monitoring is determined. Following distribute the total probability of Hazardously Misleading Information (PHMI) to each fault hypothesis by integrity risk allocation. Due to the fact that the total probability of Hazardously Misleading Information (HMI) is the sum of the product between a prior probability of the hypothesis and the integrity risk allocated under the corresponding hypothesis case, the protection level value that satisfy the allocation condition is selected as the final overall protection level. Experiment is conducted in this work to validate the MHSS method and show the fault detection and exclusion capabilities. The results of experiment reveals that the protection level calculated by MHSS can bound the attitude estimation error through the experiment period as well as the MHSS can successfully detect and exclude the faulty measurement.

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