应用于时频分析的低功耗短时傅里叶变换处理器

提出了一个应用于时频分析的短时傅里叶变换处理器.为了克服已有的离散短时傅里叶变换算法和结构的缺点,给出了一种基于快速傅里叶变换阵列的新结构.根据实际需要提出了一种新的高频域分辨率的SDF(Single-path Delay Feedback)结构FFT单元,和传统的SDF结构FFT单元相比,反馈FIFO的深度和蝶形单元的数量都有所降低.再加上开发窗函数的对称性和适当合并硬件资源,与原始设计相比处理器的功耗降低了20%.使用中芯国际0.18微米工艺实现之后,系统工作时钟可以达到200MHz,即该处理器可以满足同样频率的采样信号的实时时频分析需求.

A Low Power Short Time Fourier Transform Processor for Time-Frequency Analysis

A discrete short time Fourier transform (STFT) processor for time-frequency analysis is proposed in this paper. To overcome the drawbacks of previous discrete STFT algorithms and architectures, a new architecture based on fast Fourier transform (FFT) array is presented. An optimized single-path delay feedback (SDF) FFT architecture is proposed for high frequency resolution, which reduces feedback FIFO depth and butterfly units' number in comparison with the traditional one. Along with exploiting the symmetry of window function and performing hardware combination, power consumption decreased by 20%. The processor has been implemented with SMIC 0.18μm standard cell library, static timing analysis and dynamic simulation with timing back-annotated show that under worst-case conditions, 200MHz clock rate can be achieved, which means that the real-time time-frequency analysis demand can be fulfilled under the same sample frequency.