Calibration Method for Relativistic Navigation System Using Parallel Q-Learning Extended Kalman Filter

  • 0Science and Technology on Space Intelligent Control Laboratory, Beijing Institute of Control Engineering, Beijing 100094, China.

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Summary

This summary is machine-generated.

A novel parallel Q-learning extended Kalman filter (PQEKF) calibrates measurement bias in relativistic navigation systems. This method improves spacecraft positioning accuracy to under 300 meters in Medium Earth Orbit.

Area Of Science

  • Spacecraft navigation
  • Relativistic effects in astrodynamics
  • Estimation theory

Background

  • Relativistic navigation systems rely on precise measurements of phenomena like stellar aberration and gravitational light deflection.
  • Inter-star angle measurement bias, stemming from star sensor misalignment, significantly degrades navigation accuracy.
  • Existing methods struggle to effectively calibrate these biases in real-time.

Purpose Of The Study

  • To introduce a novel parallel Q-learning extended Kalman filter (PQEKF) for measurement bias calibration in relativistic navigation.
  • To enhance the accuracy of spacecraft position and velocity estimation by mitigating inter-star angle measurement errors.
  • To automatically tune the filter's process noise covariance matrix using Q-learning.

Main Methods

  • Development of a parallel Q-learning extended Kalman filter (PQEKF) algorithm.
  • Integration of Q-learning for adaptive tuning of the process noise covariance matrix.
  • Extraction of relativistic perturbations from inter-star angle measurements using high-accuracy star sensors.

Main Results

  • The PQEKF effectively estimates spacecraft position, velocity, and measurement bias parameters.
  • Numerical simulations in a Medium Earth Orbit (MEO) scenario demonstrate the method's high performance.
  • Achieved positioning accuracy below 300 meters with inter-star angle measurement accuracy of approximately 1 milliarcsecond (mas) after calibration.

Conclusions

  • The PQEKF offers a robust solution for measurement bias calibration in relativistic navigation.
  • The adaptive nature of Q-learning enhances the filter's ability to handle dynamic noise characteristics.
  • This approach significantly improves the overall navigation performance and reliability of spacecraft systems.

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