A two-stage technique for estimating hyperbolic frequency modulated (HFM) signal parameters is proposed. In the first stage, coarse parameter estimations are performed through a regression of the group delay estimate obtained from an unwrapped spectrum phase due to its robustness to noise. In the second stage, the coarse estimates are refined by a combination of the Newton-Raphson strategy and O'Shea refinement method. The proposed technique reaches the Cramér-Rao lower bound for HFM signal parameters, and it has better performance and lower computational complexity with respect to current state-of-the-art algorithms.

中文翻译：

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一种基于群延迟的双曲线调频信号参数估计

提出了一种用于估计双曲线调频 (HFM) 信号参数的两阶段技术。在第一阶段，粗略的参数估计是通过对从解缠频谱相位获得的群延迟估计的回归来执行的，因为它对噪声具有鲁棒性。在第二阶段，粗估计通过 Newton-Raphson 策略和 O'Shea 细化方法的组合进行细化。所提出的技术达到了 HFM 信号参数的 Cramér-Rao 下界，并且相对于当前最先进的算法具有更好的性能和更低的计算复杂度。