基于ARM的双路差分同步采样电路设计与实现

Design and Implementation of Two-way Differential Synchronous Sampling Circuit Based on ARM

随着科学技术的快速发展,FMCW雷达应用非常广泛,雷达系统对差频信号精确采集决定着测距的精度。为实现对宽带高频信号的精确采样,基于ARM单片机设计了一种双路差分同步采样电路系统。该系统不仅可以实现普通数据采样功能,还可以实现多通道、高精度、高采样率的差分同步采样功能。系统以ARM单片机为主控芯片,使用ARM内部ADC模块对雷达系统中频回波信号进行IQ双路采集,采集的数据通过DMA高速传输,距离信息通过RS232串口与外部PC通信并实时显示出来。实验分析表明:该系统能够实现5 MHz高精度多通道差分同步采样,对FMCW雷达系统中频信号差分采样,并能够适当地进行信号处理,具有体积小、通用性强等优点。

With the rapid development of science and technology,FMCW radar is widely used.Radar system's accurate acquisition of differential frequency signals determines the accuracy of ranging.In order to realize accurate sampling of broadband and high frequency signals,a dual differential synchronous sampling circuit based on ARM microcontroller was designed.The system can realize not only the common data sampling function,but also the differential synchronous sampling function with multi-channel,high precision and high sampling rate.ARM MCU was the main control chip of the system.ARM internal ADC module was used to collect the echo signal of the radar system in IQ dual channel.The collected data was transmitted at a high speed through DMA,and the distance information was communicated with the external PC through RS232 serial port and displayed in real time.Experimental analysis shows that the system can achieve 5 Hz high-precision multi-channel differential synchronous sampling for the FMCW radar system's intermediate frequency signal differential sampling,and can properly carry out signal processing,with the advantages of small size,strong versatility etc.