基于STM32实现双音多频信号(DTMF)的检测与识别

本文介绍了利用意法半导体公司的STM32F103RET芯片在完成液晶显示、键盘扫描、RTC等主控工作的同时,利用芯片集成外设模数转换器(ADC1)、定时器(TIM2)以及DMA等外设资源,完成对DTMF信号的采样。并使用软件算法完成自动增益控制,以及戈泽尔算法计算单音功率,根据信号的二次谐波功率,可靠迅速地检测和识别出按键信息。并深入讨论了戈泽尔算法中N值的取值范围,为自动增益控制的稳态功率值提供了依据。最后经过测试,完全满足ITU标准。

Based on the STM32 dual tone multifrequency signal (DTMF) detection and recognition

In this paper we introduce is the the STMicroelectronics STM32F103RET chip in the completion of liquid crystal display, keyboard scanning, RTC, master work, the use of chip integrated peripherals analog-to-digital converter (ADC1), Timer (TIM2) and DMAperipheral resources to complete the sampling of the DTMF signals. And use software algorithms to complete the AGC, and the Geze Er algorithm to calculate the single-tone power, according to the second harmonic of the signal power, rapid and reliable detection and identification of key information. The last in-depth discussion of N Ge Zeer algorithm worth range, provides a basis for the AGC value of the steady-state power.Last tested, and fully meet the ITU standard.