介紹了頻域抽取基二快速傅里葉運算的基本原理；討論了基于FPGA達4 096點的大點數超高速FFT硬件系統設計與實現方法，當多組大點數進行FFT運算時，利用FPGA內部大容量存儲資源，采用乒乓結構進行流型運算，提高FFT運算速度，同時保證結果的準確性；對實際硬件進行了FFT運算測試，測試結果證明了系統的可行性和正確性，并且利用該硬件系統成功完成了星載SAR實時成像處理。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.