A Multi-Coverage Fusion Tracking Method for LEO Targets via Space-based Netted Radar Systems

The space-based surveillance netted radar is pivotal in complementing the existing space surveillance system, which consists of space-based optical (SBO) and ground-based radar (GBR) components. It enables continuous 24-hour observation of low-orbit space targets. Given the limitations imposed by the power-aperture product (PAP) on the performance of space-based radar (SBR), this paper initially deduces the PAP requirements for SBR guided by Two-Line Elements (TLE) data. Subsequently, a space-based netted radar walker constellation is proposed to effectively blanket the low-orbit space, facilitating cooperative relay observation of low-orbit space targets. The paper also employs the covariance intersection (CI) fusion algorithm to estimate the motion state of space targets, thereby enhancing the tracking accuracy of the space surveillance system for low-orbit targets. Experimental results indicate that the space-based surveillance netted radar achieves an observation coverage rate of 87.7%, significantly improving the surveillance system's observation frequency and cataloging performance for space targets.