摘 要随着的发展人们的生活质量越来越高，许多事物都追求方便、高效，测距在计算机、机器人等工业化的发展中都应用广泛。因为超声波是一种纵向机械波所以是直线传播并且符合反射和折射的特性。超声波传感器结构简单、体积小、经济并且方便集成化。利用超声波以一定速度定向传播等特性设计的超声波测距主要应用在建筑施工现场测量、倒车提醒等防撞系统、移动机器人定位等。超声波测距具有可靠性、精度可控、应用广、高效等优点。FPGA 是现场可编程门阵列，I/O 口多、能够并行运算、集成度高。常用的门电路或者是复杂组合逻辑电路都能用简单的程序实现。利用 FPGA 能简便控制时序的特点本文对超声波的特性设计了基于 FPGA 的测距系统,通过 FPGA 中的全局的时钟分频信号处理对超声波信号的收发有准确的控制。在一定的工作环境下，通过测量超声波往返时间已知超声波的传播速度就能计算出来与目标物的距离。关键词：超声波测距；FPGA；分频AbstractWith the development of people's quality of life is getting higher and higher, many things are pursuing convenience and efficiency, ranging is widely used in the development of computer, robot and other industrialization. Because ultrasound is a longitudinal mechanical wave, it propagates in a straight line and conforms to the characteristics of reflection and refraction. The ultrasonic sensor is simple in structure, small in size, economical and easy to integrate. Ultrasound ranging, which is designed with the characteristics of directional propagation of ultrasound at a certain speed, is mainly used in anti-collision systems such as building construction site measurement, reverse warning, mobile robot positioning and so on. Ultrasound ranging has the advantages of reliability, controllable accuracy, wide application and high efficiency..FPGA is a field programmable gate array with many I/O ports, parallel operation and high integration., parallel computing, and high integration. Commonly used gate circuits or complex combinational logic c...
