基于超大规模FPGA的FFT设计与实现

Design of FFT operation based on ultra large scale FPGA

在宽带数字接收机中,需要对数字检波输出的信号流进行实时FFT运算。提出了一种用于宽带数字接收机的基于Xilinx的Virtex-IV芯片的高速FFT的设计与实现方法,采用了多级串行流水线结构及优化的数据存取方式,设计出用单片FPGA实现了2048点实数的FFT方案。其完成2048点FFT的时间约为4.57μs,能很好地满足系统处理的实时性要求,在工程实践中有很大的应用前景。

The speed of carrying out a FFT operation has been improved due to the using of ultra very large scale Field Programmable Gate Array（FPGA）. It is needed to carry out a FFT operation on the digital signal stream which is outputted by a digital detector of a wide band digital receiver. The paper studied a method of high speed FFT operation based on the Xilinx Virtex- IV FPGA, the module of FFT operation is used in a wideband digital receiver. A structure of multilevel serial pipeline is brought forward, and the mode of reading and writing date is optimized too. Based on the method, a FFT operation on 2 048 points real can be carried out on a single piece of FPGA. The time of the FFT operation need is 4.57 μs, which can meet the real-time processing of a wide band receiver.