基于FPGA的数字磁通门传感器系统设计和实现

Design and Realization of FPGA-based Digital Fluxgate Signal Sensor System

针对传统磁通门信号处理电路中模拟元件的缺点,设计一种基于现场可编程门阵列(FPGA)的数字磁通门系统。整个系统采用闭环结构,由激励产生模块、信号处理模块和负反馈模块组成。外围模拟电路用高速D/A、A/D芯片取代,有利于系统温度稳定性的提到。FPGA内的数字逻辑实现了磁通门信号解算、激励正弦信号发生、D/A、A/D输入/输出串并转换的功能,首先用硬件描述语言(HDL)设计并仿真,然后下载、配置到FPGA中,调试完成后进行实验,通过实时处理双铁芯磁通门传感器探头输出信号对系统进行测试。实验结果证实了系统功能的正确性。闭环结构的采用提高了系统信号梯度线性度,与模拟系统相比,基于数字逻辑的设计温度性能更稳定,更易于小型化,可移植性更强。

Aiming at the drawbacks of analog components in traditional fluxgate device,a FPGA-based（Field Programmable Gate Array） fluxgate sensor system is designed.The system adopts closed-loop structure,consists of excitation generation module,signal processing module and degenerative feedback module.The periphery analog circuitry is substituted by fast AD converter and DA converter,which is in favor of the system robustness over temperature.The digital logic in the FPGA chip realizes the function of fluxgate signal demodulation excitation sinusoidal signal generation and DA/AD output/input deserialization,firstly it is designed in HDL（Hardware Description Language）,afterward configurated,finally tested by processing digital outputs of a double-core fluxgate sensor probe in real-time,the functionality of the designed system is verified.Closed-loop structure optimizes the signal gradient linearity,and,this FPGA-based design has reliable temperature,feasible miniaturization and high portable compared with analog system.