一种快速FFT捕获算法及其FPGA实现研究

典型FFT捕获方法可以完成码相位的并行捕获,较滑动相关方法可以更快捕获GPS信号,但是仍比较耗时。利用频域移动等于时域乘以指数信号的特性,可以在1ms时间内完成多普勒频率的搜索,实现码相位和频率域的同时并行捕获,给出了FPGA实现的结构设计,结果表明该方法资源消耗小,捕获速度快,是一种优秀的快速捕获技术。

Research on Fast FFT Acquisition Algorithm and its Realization on FPGA

FFT capture method can implement code phase parallel acquisition,and capture GPS signals faster than the classical sliding methods,but also consumes much time.As time domain signal multiplication by an exponential signal equals frequency domain move,by the features,frequencies of doppler search can be completed in 1ms to enforce parallel capturing in both code phase and frequency domain.The structure design is presented based on FPGA,and it proves that this method is excellent for expending less resource,and captures signal much fast.