基于FPGA的超高速FFT硬件實(shí)現(xiàn)

介紹了頻域抽取基二快速傅里葉運(yùn)算的基本原理；討論了基于FPGA達(dá)4 096點(diǎn)的大點(diǎn)數(shù)超高速FFT硬件系統(tǒng)設(shè)計(jì)與實(shí)現(xiàn)方法，當(dāng)多組大點(diǎn)數(shù)進(jìn)行FFT運(yùn)算時(shí)，利用FPGA內(nèi)部大容量存儲(chǔ)資源，采用乒乓結(jié)構(gòu)進(jìn)行流型運(yùn)算，提高FFT運(yùn)算速度，同時(shí)保證結(jié)果的準(zhǔn)確性；對(duì)實(shí)際硬件進(jìn)行了FFT運(yùn)算測(cè)試，測(cè)試結(jié)果證明了系統(tǒng)的可行性和正確性，并且利用該硬件系統(tǒng)成功完成了星載SAR實(shí)時(shí)成像處理。In this paper, the basic principle of decimation-in-frequnency radix-2 FFT algorithm is briefly presented. Then, the design and realization methods of hardware system with FPGA are thoroughly discussed, with which it is easy to implement the FFT algorithm of large points－4 096 points. The FFT-speed of many groups of large points is accelerated greatly through ping-pong-ram. Finally, this hardware system is turned out to be feasible and accurate through the FFT algorithm experiment. Furthermore, the real-time imaging procession of airborne SAR can be accomplished successfully by this hardware system.