基于CP-GTD模型的三维散射中心参数估计

摘要

散射中心是目标光学区电磁散射的基本特征,可反映目标精细物理结构.在建立精确描述目标高频电磁散射的三维CP-GTD模型的基础上,根据散射中心类型和位置参数的弱耦合性,提出基于三维ESPRIT方法估计目标全极化三维散射中心的位置,进而利用特征分析中信号子空间与噪声子空间的正交性和最小二乘方法,实现散射中心类型和相干极化散射矩阵的估计.与现有基于单极化观测模型的估计方法相比,所提方法不仅具有更好的估计性能与抗噪能力,而且能够直接估计出目标散射中心的相干散射矩阵,仿真实验验证了上述结论的正确性.%As a basic characteristic of radar target in high frequency domain, scattering centers can characterize its elaborate physical structure.Using the weak coupling property between the type and position parameters of a scattering center, the three-dimensional (3D) position parameters were estimated via an ESPRIT method based on the foundation of 3D Coherent Polarimetric GTD (CP-GTD) model.Then the types of scattering centers were estimated on the orthogonality between the signal subspace and noise subspace, while the least square method was used to calculate the coherent polarimetric scattering matrices.Compared to existing estimation methods based on the mono-polarization model, the proposed method provides better estimation performance and stronger noise resistance,and can estimate the coherent scattering matrices of scattering centers directly. Simulation results show its effectiveness and robustness.