论文部分内容阅读
三、逐次式FFT处理机介绍一种实时处理20千赫音频信号的FFT处理机,即每秒实时处理采样点数为40×10~3。模数转换器ADC可直接把数据送往FFT处理机,FFT处理最大样点数N为1024,输出送往通用计算机。这种FFT处理机采用逐次式的结构,其方块图示于图10。它由数据存储器、三角函数表只读存储器、结果缓冲存储器、蝶形运算单元、变址器、控制器等组成。 (一)存储器由于实时处理的需要,在数据存储器Ⅰ和Ⅱ之间轮换进行FFT运算与接收模数转换器ADC送来的数据,这是在转换开关Ⅰ和Ⅱ的作用下完成的。数据存储器Ⅰ和Ⅱ完全相同,功能也相同,都是接收原始数据、存放中间运算结果的。每个存储器都有1024个
Third, the sequential FFT processor introduces a real-time processing 20 kHz audio signal FFT processor, that is, real-time processing of sampling points per second 40 × 10 ~ 3. ADC ADC can be sent directly to the FFT processor, FFT processing the largest sample of N 1024, the output sent to a general-purpose computer. The FFT processor uses a sequential structure, and its block diagram is shown in FIG. 10. It consists of data memory, trigonometric function table read-only memory, the results of the buffer memory, the butterfly operation unit, the indexer, the controller and so on. (A) due to the need of real-time processing memory, rotate between the data memory Ⅰ and Ⅱ FFT operation and receive ADC data sent, which is in the role of the switch Ⅰ and Ⅱ completed. Data Memory I and II exactly the same function is the same, are receiving raw data, store the results of the operation. 1024 for each memory