基于FPGA的激光测距系统中基4算法的FFT研究

The Research of Radix-4 Algorithm FFT for Laser Ranging System Based on FPGA

文章提出了利用可编程逻辑器件FPGA通过硬件来实现快速傅立叶变换(FFT)的基4算法,提出了采用两个蝶形运算器同时并行计算,每次蝶形运算按顺序进行的结构,将并行处理与顺序处理相结合,提高并行度和数据吞吐量,每次蝶形运算时间不超过1μs,完成整个256点复数FFT运算大约需要120μs左右,同时又节省资源。该方法在激光矿井提升机位置跟踪系统中应用取得了良好效果。

In this paper,Radix-4 algorithm of FFT is introduced,which is realized by using hardware of FPGA (Field Programmable Gate Array).Structure that two butterfly arithmetic unit compute parallel and simultaneity is given,and butterfly arithmetic acts sequentially every time.In this structure,pairing processing and sequential processing are associated.This approach can improve parallelism and throughput.Each butterfly arithmetic time is not more than 5μs,and the whole 256 dot plural FFT arithmetic need about 120μs.At the same time source is saved.When it is applied in position following system of mine hoist,nicer effect is obtained.