Space observation data preliminary analysis of XPNAV-1 satellite

The X-ray pulsar-based navigation-1 (XPNAV-1) is China’s first space experimental platform dedicated to exploring X-ray pulsar navigation technology. It has been in orbit for over seven years, accumulating a large amount of observational data. This work collects nearly four years of space observation data from the satellite and conducts valuable technical research explorations. Firstly, the satellite’s observation data on the Crab pulsar is processed and analyzed. The pulse profiles of the Crab pulsar per orbit, per day, and the total pulse profile are obtained. The results indicate that the pulse profile is stable in the temporal dimension, showing good consistency with domestic and international observational results. Different energy range pulse profiles of the Crab pulsar are obtained, and the characteristics of pulse profile variation with energy are analyzed. In the energy dimension, the energy spectra of the Crab pulsar in different pulse phase intervals are obtained. It is found that the energy spectrum is proportional to the pulse intensity in the phase interval, indicating that the domestically developed focusing X-ray detector is in good technical condition and has achieved the experimental goal of accurately “seeing” the pulsar from the satellite. Finally, using three days of observation data from the XPNAV-1 satellite, pulsar navigation test solutions based on the least squares algorithm are achieved. The satellite’s orbit determination accuracy is approximately 56.93 km. Analysis reveals that the current navigation solution accuracy is severely affected by observation errors of XPNAV-1 towards the Crab pulsar and initial orbit errors.