基于FPGA的二维PSD信号处理系统设计  

Design of two-dimensional PSD signal processing system based on FPGA

作　　者：张天宇 贾方秀 周强 李浩 ZHANG Tianyu;JIA Fangxiu;ZHOU Qiang;LI Hao(ZNDY of Ministerial Key Laboratory,Nanjing University of Science andTechnology,Nanjing 210094,China)

机构地区：[1]南京理工大学智能弹药技术国防重点学科实验室

出　　处：《中国测试》2019年第8期135-139,共5页China Measurement & Test

基　　金：国家自然科学基金（61201391）

摘　　要：为实现对入射光斑位置坐标的精确测量,设计以FPGA为核心的二维PSD信号处理系统。针对窄脉冲激光照射下前置放大放电路,建立相应等效噪声模型,引入频率对电路输出电压噪声的影响得到提高电路分辨率措施。搭建自动增益控制电路,并结合FPGA给出的相应增益控制策略实现对幅值大动态范围变化的光电流合理放大。设计峰值脉冲检测电路实现窄脉冲信号峰值的准确测量,其测量误差小于3%。通过FPGA设计状态机实现A/D芯片模式配置和数据读取,并搭建相应坐标解算模块和串口模块,实现入射光斑坐标的解算与传输。实验表明该系统测量非线性度小于10μm,测量精度高。In order to realize the precision measurement of the incident spot coordinates,the two-dimensional PSD signal processing system based on FPGA was designed.The noise model of amplifier circuit under the narrow pulse laser irradiation was established and the effect of frequency on the output voltage noise was introduced to improve the resolution of the circuit.The large dynamic range photocurrent was amplified by the AGC circuit according to the gain control strategy and the peak value of pulse signal was detected by the peak detection circuit and the error is less than 3%.The A/D chip configuration and data reading were realized by the state machine of FPGA and the coordinate solving model and the UART model was also established to realize the solution and transmission of the incident spot coordinates. Experiment shows that nonlinearity of system is less than 10 μm.

关 键 词：位置敏感探测器 窄脉冲信号处理 自动增益控制电路 峰值检测电路 FPGA 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]