GNSS软件接收机新型高灵敏度捕获算法及实现

New high-sensitivity acquisition method and implementation for GNSS software receiver

针对下一代卫星导航系统(如伽利略系统和GPS现代化系统等)软件接收机中信号捕获出现的数据跳变问题,提出了一种基于能量的新型高灵敏度捕获算法。该算法是在时域并行FFT捕获技术基础上,对二维搜索空间进行适当修改,在频率搜索维上采用基于能量的搜索策略。同时结合采用非相干积分技术,进行数据和导频双通道组合捕获,使噪声影响进一步减少。通过伽利略仿真信号进行实验,结果表明能量捕获算法既能克服数据跳变对捕获的影响,又能将噪声进行适度平均,从而减少误捕率,可实现适度低信噪比条件下的高灵敏度捕获。

A new energy-based high-sensitivity acquisition method is proposed for solving the problem of data transition during the acquisition of the next-generation GNSS signals （as Galileo, and GPS modernization）. The basic idea proposed consists in a modification of the 2-D function evaluated in the search space based on time domain FFT parallel acquisition and utilizes an energy-based method on frequency search space to recover the data transition position. bility is reduced. In the data and pilot channels Simulation of Galileo signals shows it performs a noise average, the false alarm proba meantime, combining with long data non-coherent integration and acquisition on both further mitigate the noise influence to achieve moderate high-sensitivity acquisition.