In this study, by employing the intra-pulse cross-correlation (IPCC) operation, an unambiguous velocity estimation method is proposed for narrow-band long-range radars with high carrier frequency and low pulse repetition frequency. This estimation algorithm is simple and could be easily implemented in existing radar systems without changing the radar hardware or the pulse transmitting scheme. Comparing with the slow time dimension correlation algorithm, the accuracy of the proposed intra-pulse frequency domain method is greatly improved, and the brute-force search for the unknown motion parameters is also unnecessary. By first setting a small frequency offset of the IPCC operation, the unambiguous velocity region could be significantly enlarged. Using the relatively coarse but unambiguous estimates and increasing the frequency offset step by step, the IPCC is repeatedly applied to obtain more accurate estimates. Note that the estimation results of the IPCC algorithm could be used in the maximum-likelihood estimator for ambiguity resolution. The Cramér-Rao bound for the proposed algorithm is derived, and the optimal frequency offset in the sense of estimation accuracy is also analysed. Through numerical simulations for both synthetic and real radar data, the effectiveness of the proposed estimation algorithm is verified.

中文翻译：

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基于脉冲内互相关的明确速度估计方法

在这项研究中，通过使用脉冲内互相关（IPCC）操作，为具有高载波频率和低脉冲重复频率的窄带远程雷达提出了一种明确的速度估计方法。该估计算法很简单，可以在不改变雷达硬件或脉冲传输方案的情况下，在现有雷达系统中轻松实现。与慢时维相关算法相比，所提出的脉冲内频域方法的精度大大提高，并且不需要对未知运动参数进行强力搜索。通过首先设置IPCC操作的较小频率偏移，可以明显扩大明确的速度区域。使用相对粗略但明确的估算并逐步增加频率偏移，IPCC被反复应用以获得更准确的估计。注意，IPCC算法的估计结果可用于最大似然估计器中，以消除歧义。推导了所提出算法的Cramér-Rao界，并从估计精度的角度分析了最佳频率偏移。通过对合成和真实雷达数据进行数值模拟，验证了所提算法的有效性。