An autonomous hybrid navigation filter using earth magnetic field measurements for low earth orbit satellite

The primary focus of this paper is the design of an hybrid navigation filter algorithm based on Extended Kalman Filter (EKF), which autonomously and simultaneously estimates three axis attitude, rate and orbit using only Earth Magnetic Field (EMF) measurements. The presented hybrid navigation filter algorithm is based on the laws of orbital mechanics, attitude dynamic and the EMF measurements. According to our simulations study, the developed hybrid navigation filter shows the capability of estimating the attitude with accuracy less than 1.5 deg and rate order is 1.5 milli-deg/sec. In orbit estimation, the filter is able of estimating the position with accuracy of 15.5 km and velocity 0.013 km/s. Based upon results, the orbit and attitude accuracy is sufficient for Low Earth Orbit (LEO) satellite with coarse accuracy mission requirements and it can be used as a backup system to provide redundancy.