The Spacecraft Parabolic Antenna Payload Orientation Estimation Method Based on the Step Effect of Measured Radar Cross Section Sequences

The analysis and processing of active radar image information is an important method for determining the payload orientation of non-cooperative targets. However, a challenge for spacecraft carrying parabolic antenna payloads is that active radar imaging is susceptible to defocus, making it difficult to achieve a reliable estimate of the orientation of such payloads. As such, this paper proposes a method for estimating the orientation of spacecraft parabolic antenna payloads based on radar-measured radar cross section (RCS) sequence data. By utilizing the step effect produced when the ground-based radar observes the parabolic antenna payload, the mathematical model for estimating the orientation of the parabolic antenna payload is established through the analysis of the geometric relationship between the radar observation vector and the antenna payload orientation in the orbital coordinate system. This method employs an optimized model and particle swarm optimization to achieve the pointing estimation of the parabolic antenna payload. The simulation results demonstrate that the proposed algorithm can accurately estimate the pointing direction of the antenna payload, with the maximum error being better than three degrees, and it has good robustness. The results of real data processing further verify the effectiveness of the algorithm.