OFDM中FFT处理器的设计及FPGA实现

Design and FPGA implementation of FFT processor for OFDM

介绍了OFDM技术及其应用在电力线通信中的优势,并指出了FFT的高速实现在OFDM中的关键性。针对OFDM中FFT的运算要求,研究了一种易于FPGA实现的FFT处理单元的方案。该方案采用基2DIT-FFT算法以及单元结构的设计思路,给出了改进的基于顺序处理的FFT结构。用VHDL语言对各个模块进行编程,并在QuartusⅡ软件环境下综合仿真,时序分析结果与MATLAB计算结果相比验证了设计的正确性,可以满足某些OFDM系统的需求。

The OFDM technology and the superiority of its application in the power line communication were introduced. And the crucial nature of FFT high speed realization in the OFDM was pointed out too. In view of the request of FFT operation in OFDM, one method of FFT processing unit was studied which was easy to realize based on FPGA. This plan used the radix-2 DIT-FFT algorithm as well as the design mentality of cellular structure. It has given the improved FFT structure based on the sequential processing, and used the VHDL to program each module and simulated comprehensively under the Quartus II software environment. The accuracy of design has been confirmed by comparison between the result of succession analysis and the calculating result of MATLAB. It can satisfy the demand of some OFDM systems.