基于批处理的改进FFT微弱信号捕获算法及其实现

Implementation of Improved FFT Weak Signal Acquisition Algorithm Based on Batch Method

为了解决全球定位系统(Global position system,GPS)微弱信号的快速捕获问题,在基于快速傅里叶变换(Fourier transform,FFT)捕获方法的基础上,改进过去的相干积分或非相干积分,提出了一种新的改进微弱信号捕获算法,采用批处理方式提高捕获增益,并运用多普勒补偿,提高信号累加时间容限,进一步提高信号捕获灵敏度。仿真测试表明,该方法较传统的FFT算法,提高了捕获概率,最后在FPGA上具体实现了该方案。

To solve the problem of rapid acquisition for weak signal in the global position system （GPS）, a new improved weak signal acquisition algorithm is proposed, which improves the past coherent and incoherent integral gain based on fast Fourier transform （FFT）. The proposed method uses batch mode to improve capture gain by adopting Doppler compensation and improves signal accumulate time tolerance. Moreover, the method can further improve the signal capture sensitivity. Comparing with traditional algorithm the capture probability rises greatly and it is proved by lots of simulation tests. Finally, the method is implemented on FPGA.