【摘要】 基于Radix-22 SDF(single-path delay feedback)的蝶形运算结构设计了一个级数在64、256、1024、2048之间可选的可伸缩FFT(Scaleable FFT)处理器,以较少的硬件规模满足了宽带自适应正交频分复用(OFDM)传输系统子载波数目可变、数据流量高、低处理延迟、设置灵活的处理要求。文中还针对输入OFDM信号的波形分布特性,仿真分析了该FFT处理器在采用不同的中间处理字长和旋转因子量化字长时其输出信噪比和所占用逻辑单元数目的变化,并据此合理选择了实现参数,在性能提高的同时有效减少了其硬件规模。更多还原

【Abstract】 A 64/256/1024/2048-point scaleable FFT processor is presented.It is based on the Radix-22 SDF(Single-path Delay Feedback) butterfly architecture,and is very suitable for broadband adaptive OFDM communication system,where variable number of sub-carriers,high throughput,low latency and configuration flexibility is required.Considering the OFDM waveform characteristics,the output SNR and logic cell consumption with respect to different internal word-lengths and rotation factor quantization precisions are simulated and analyzed.Then implementation parameters are appropriately selected,which leads to a higher output performance while a less hardware consumption.更多还原