Abstract: Low-angle estimation for very high frequency (VHF) radar is a difficult problem due to the multipath effect in the radar field, especially in complex scenarios where the reflection condition is unknown. To deal with this problem, we propose an algorithm of target height and multipath attenuation joint estimation. The amplitude of the surface reflection coefficient is estimated by the characteristic of the data itself, and it is assumed that there is no reflected signal when the amplitude is very small. The phase of the surface reflection coefficient and the phase difference between the direct and reflected signals are searched as the same part, and this represents the multipath phase attenuation. The Cramer-Rao bound of the proposed algorithm is also derived. Finally, computer simulations and real data processing results show that the proposed algorithm has good estimation performance under complex scenarios and works well with only one snapshot.

甚高频雷达复杂场景中目标高度和多径衰减联合估计

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