Single XNAV integrated navigation based on series filtering

Abstract

Celestial navigation system (CNS) and inertial navigation system (INS) are traditional autonomous integrated navigation methods. CNS is generally used to correct the cumulative error of the gyroscope in INS. The cumulative error of the accelerometer in INS cannot be corrected. As a new type of autonomous navigation method, the X-ray pulsar navigation system (XNAV) can correct the cumulative error of the accelerometer.This study proposes an integrated navigation method based on a combination of single x-ray pulsar navigation (SXPN), INS, and CNS. The method constructs a virtual accelerometer (VA) by coordinate system transformation, then compensates the error of the virtual accelerometer by using single X-ray pulsar navigation method, and then estimates the position, velocity, and angle errors by Kalman filtering method. The proposed method is an improvement of the SXPN navigation method of Q. Xu et al. in 2018. These improvements are twofold, that is, the positioning has high accuracy and is stable. A method was proposed to correct the error of the accelerometer and then analysis and simulation to support our guess is provided. This navigation method not only can correct the zero-order error of the accelerometer but also the first-order error that few scholars have studied.Simulations show that the proposed method reduces the total position error in three directions. In comparison with the method of adding the pulsar arrival time directly to the observation equation, our proposed method not only has higher precision, but it can also alleviate the jitter of the velocity position and attitude curve.