摘要
本文基于TMS320F2812 DSP芯片,设计并实现了一台音频数字扫频仪。采用SPWM调制方法,运用DDS原理寻址正弦表,使用DSP的GP定时器产生占空比按正弦规律变化的PWM波,将滤波调理后得到的扫频信号加到带阻网络输入端,再对带阻网络前后端信号采样,进行频域及时域求解,最后在上位机中绘制出幅频特性曲线。该数字音频扫频仪充分利用了DSP内部的资源,处理速度快,抗干扰能力强,扫频精度高。
A digital audio frequency sweeper （DAFS） is designed and implemented on TMS320F2812 DSP in this paper. The PWM wave whose duty cycle is changing regularly as the sine wave is produced with SPWM modulation, the principles of DDS which is used to address the sine table, and GP timer. After filtering and adjusting circuits, signals go through the bandstop network whose outputs are sampled and calculated in both frequency domain and time domain. Finally, the am- plitude-frequency curve is drawn by software in the host computer. This DAFS fully takes the advantages of the DSP internal resources, runs quickly, and has a strongly anti-interfere ability and high accuracy.
出处
《信息化研究》
2011年第1期58-62,共5页
INFORMATIZATION RESEARCH
