作者：蔡璨, 贾云飞, 张燕强

作者单位：南京理工大学机械工程学院，江苏 南京 210094

关键词：未爆弹探测;数据采集系统;数字滤波;FPGA

摘要：

针对未爆弹探测提出的多通道同步采集、大量数据传输处理等问题，研制电磁法多通道同步探测系统。系统包含激励变频系统，能够通过指令改变激励频率以应对不同环境要求，提高探测效率；针对传感器的差分阵列结构，优化时钟总线，可以对32路16对信号同步采集，提升信噪比，增大探测面积；针对未爆弹探测中的数据量大，对数据传输处理要求高，充分利用FPGA逻辑资源实现正交锁相和IIR数字滤波器，有效提取目标电磁耦合后的信号幅值特征值，将数据处理和计算在FPGA内实现，降低数据传输要求，上位机性能要求也随之降低，使得探测系统结构更加紧凑。使用具有16对通道的线圈传感器和模拟被测物体对系统进行测试，实验结果表明：该套系统多通道采集具有同步性，且子板FPGA内部算法的输出结果可以反映目标特征。

Research on multi-channel synchronous detection system of unexploded projectile based on electromagnetic method
CAI Can, JIA Yunfei, ZHANG Yanqiang
School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Abstract: Aiming at the problems of multi-channel synchronous acquisition and large-scale data transmission processing raised by unexploded ordnance detection, an electromagnetic multi-channel synchronous detection system was developed. The system includes an excitation frequency conversion system, which can change the excitation frequency through instructions to respond to different environmental requirements and improve detection efficiency. For the differential array structure of the sensor, the clock bus is optimized, and 32 channels (16 pairs) of signals can be synchronously collected to improve the signal-to-noise ratio and increase detection area. In view of the large amount of data in the detection of unexploded bombs and high requirements for data transmission and processing, make full use of FPGA logic resources to achieve quadrature phase lock and IIR digital filters, and effectively extract the signal amplitude characteristic value of the target after electromagnetic coupling. Realize data processing and calculation in FPGA, reduce the data transmission requirements, and the performance requirements of the upper computer are also reduced, making the detection system structure more compact. The system is tested using a coil sensor with 16 pairs of channels and a simulated object under test. The experimental results show that the multi-channel acquisition of the system is synchronized, and the output results of the internal algorithm of the daughter board FPGA can reflect the target characteristics.
Keywords: UXO detection;data acquisition system;digital filter;FPGA
2020, 46(12):47-53  收稿日期: 2020-08-23;收到修改稿日期: 2020-11-25
基金项目:
作者简介: 蔡璨(1996-),男,新疆呼图壁县人,硕士研究生,专业方向为测试技术
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