Enhanced precision attitude determination algorithms

In this paper, a robust filtering scheme is developed to enhance the performance of the attitude determination system (ADS). The filter structure is constructed based on extended Kalman filtering (EKF) scheme to accommodate for nonlinear measurement process; however, the overall filtering scheme is augmented with two additional mechanisms to provide appropriate treatments to the nonwhiteness and nonstationary signals arising from the ADS sensor package. These two mechanisms are nonwhite noise identifier and white noise covariance updater for the EKF process noise and measurement noise matrices. The first mechanism is aimed to address the nonwhiteness and nonstationary ADS noises by reconstructing them for cancellation at the measurement level while the second mechanism is intended to fine-tune the performance of the EKF, thereby providing the EKF with an operational condition to produce enhanced precision attitude determination performance.