The existing methods of altitude measurement for low-angle targets adopt the specular reflection surface model, and the direct and multipath signals are considered as two correlated far-field point sources. However, in reality, the wavefront of multipath signal is distorted by irregular reflection surface, and the far-field point source model is not enough to describe the multipath signal. To deal with this model mismatch problem, the low-angle multipath model is mainly studied. This paper begins with a discussion of classical multipath model and is followed by the inversion method of reflection coefficient and the height of reflection surface. Then the perturbation of the multipath signal caused by irregular reflection surface is modeled as perturbational reflection coefficient and a perturbational multipath model is developed with a maximum likelihood method to invert the proposed parameter. Simulation data processing results validate the effectiveness of the inversion method. The effectiveness of the proposed model and inversion method are validated by measured data processing results. These research results can provide valuable information for enhancing the applicability of the low-angle altitude measurement method in practical situations.
郑轶松, 陈伯孝. 米波雷达低仰角目标多径模型及其反演方法研究[J]. 电子与信息学报, 2016, 38(6): 1468-1474.
ZHENG Yisong, CHEN Baixiao. Multipath Model and Inversion Method for Low-angle Target in Very High Frequency Radar. JEIT, 2016, 38(6): 1468-1474.
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