摘要
提出了一种全球定位系统(GPS)信号捕获原理,详细介绍了基于快速傅里叶变换(Fast Fourier Transform,FFT)结合非相干累积的GPS信号捕获方法。描述了基于可编程门阵列器件(FPGA)的通过数字正交下变频、本地载波产生、部分匹配滤波、FFT分析、非相干累积和信噪比估计的具体实现过程。以实际GPS信号为例进行仿真,结果表明此方法可以满足高动态低信噪比环境下GPS信号快速捕获需求。
To solve the problem that the capture time of GPS signals is too long in high dynamic and low SNR environments,a fast acquisition method based on fast Fourier transform（FFT） and incoherent accumulation is presented.A FPGA-based implementation process for the acquisition system is described in detail,which includes digital quadrature down conversion,local carrier generator,partial matched filter,FFT,incoherent accumulation and SNR estimation,.The simulation results show that the method is robust and rapid.
出处
《无线电工程》
2012年第3期34-37,共4页
Radio Engineering
