Space‐based automatic dependent surveillance‐broadcast (ADS‐B) is an important emerging augmentation of existing ground‐based ADS‐B systems. In this paper, the problem of space‐based ultra‐long‐range reception processing of ADS‐B signals is described. We first introduce a header detection method for accurately determining the pulse position of a weak ADS‐B signal. We designed a signal encoding method, shaping method, and fitness function. We then employed a genetic algorithm to perform high‐precision frequency and phase estimations of the detected weak signal. The advantage of this algorithm is that it can simultaneously estimate the frequency and phase, meaning a direct coherent demodulation can be implemented. To address the computational complexity of the genetic algorithm, we improved the ratio algorithm for frequency estimation and raised the accuracy beyond that of the original ratio algorithm with only a slight increase in the computational complexity using relatively few sampling points.

中文翻译：

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基于遗传算法的微弱空基ADS-B信号参数估计

天基自动相关监视广播（ADS-B）是现有地面ADS-B系统的重要新兴扩展。本文描述了ADS-B信号的空基超远程接收处理问题。我们首先介绍一种报头检测方法，用于准确确定弱ADS-B信号的脉冲位置。我们设计了一种信号编码方法，整形方法和适应度函数。然后，我们采用遗传算法对检测到的微弱信号进行高精度的频率和相位估计。该算法的优势在于它可以同时估计频率和相位，这意味着可以实现直接相干解调。为了解决遗传算法的计算复杂性，