莫尔条纹信号的DSP滤波及细分技术研究

采用DSP数字滤波技术,对细分前的莫尔信号进行滤波处理。以提高莫尔信号的细分精度和实时性,利用DSP的乘加指令及循环寻址功能设计了FIR滤波器,实现莫尔条纹信号的实时滤波,将合成函数细分与幅值细分相结合,减少了存储查表数据所需的存储单元、提高了细分速度和细分精度。实验结果表明,在较强干扰的情况下,细分倍数仍能达到500,整个细分和滤波算法可在几微秒内完成,因而系统的实时性能很好。

Study on DSP filter and subdivision of Moirefringes signal

The filtering processing of Moire fringe signal before subdivision is performed with DSP digital filtering techniques for improving subdivision accuracy and real time of Moire fringe signal. FIR filtering program is designed by using the multiplying and adding commands and cycle addressing functions of DSP for performing real-time filtering of Moire fringe signal. The storage units required to storage table-look-up data are reduced by combining composite function subdivision with amplitude subdivision, thus improving subdivision accuracy and speed. The experimental results show that under the conditions of a stronger disturbance the subdivision times can be up to 500. The whole subdivision and filtering algorithm can be finished in several microseconds, nearly in real time.