THREE-DIMENSIONAL IMAGING OF SPATIAL SPINNING GROUP TARGETS BASED ON EXTENDED KALMAN FILTER AND INVERSE RADON TRANSFORM

Ballistic missiles have become an important weapon in modern military wars by their strong penetration ability, wide striking range and high accuracy in hitting targets. In the mid激course, the missile releases warheads, debris and decoys, which form a spatial group targets. And each of them usually achieves spatial orientation by spinning motion. This complex motion brings great challenges to the radar imaging. Based on the extended Kalman filter and inverse Radon transform, a three-dimensional imaging method for spatial spinning group targets is proposed in this paper. First, the sine curves in the range-slow-time plane are separated by extended Kalman filter, and the height coordinates of scatterers are estimated by the offset of the curves. Then the spinning angular velocity of each scatterer can be analyzed by the empirical mode decomposition, which reveals the number of sub-targets. Finally, on the basis of above estimation, the three-dimensional reconstruction of each sub-target is carried out by the inverse Radon transform. This algorithm reduces the dimensionality of traditional search with curve separation techniques, thereby significantly improving the computational efficiency. Simulation results verify the effectiveness of the proposed method.