基于FPGA的超声波传感器前端电路设计

超声波传感器广泛应用于风速、风向的测量,前端电路的设计直接关乎系统性能的好坏.为达到稳定的驱动效果,驱动电路采用了低压驱动方式.为能接收稳定、准确的超声波信号,设计了接收及信号处理电路,进行接收抗干扰限幅处理、前置放大、带通滤波、自动增益控制放大和电压比较,将所接收的超声波交变电压信号转换成可供FPGA 直接使用的数字信号.实验结果验证,各个电路模块的设计均满足系统要求.

Design of front-end circuits for ultrasonic sensor using FPGA

Ultrasonic Sensors is widely used in the measurement of wind speed and direction,and the system performance is directly related to the design of front-end circuits.In order to achieve steady driving effect,drive circuit uses a low voltage drive mode.In order to insure the ultrasonic singal that received are stable and accurate,we design the receiving circuit and signal processing circuit,then conducting the anti-interference limit processing,preamplifier,band-pass filter,automatic gain control amplifier and voltage comparison.The ultrasonic alternating voltage signal that received are converted into the digital singal that FPGA can use directly.The experimental results have indicated that the design of each circuit module can meet the demand of system.