基于FPGA的电磁脉冲电场测量系统

为了测量纳秒级前沿的电磁脉冲电场,研制了一种基于现场可编程门阵列(FPGA)的宽频带电磁脉冲电场测量系统,该系统采用单极子天线作为电场探头的接收天线,高速AD采集调理电路输出的电压信号,由FPGA接收AD采样的数据并保存至DDR2和FLASH存储器中;分析了系统的整体方案;对系统的信号调理、采集的触发方式、FPGA控制以及干扰屏蔽等关键技术进行了重点分析;通过电场探头、电磁脉冲模拟器、PTEM暗室、衰减器以及示波器进行了性能和功能验证实验;利用软件将电场探头和示波器测得的信号进行处理和对比;实验表明,所研制的电场探头可以测量前沿大于2.5ns、电场强度为0~50kV/m的脉冲电场,系统线性度好,体积小,抗干扰性能好,测量准确性高。

Development of electromagnetic pulse measurement system based on FPGA

In order to measure the electric field of electromagnetic pulse with nanosecond rise time, a kind of broad-band electric field of electromagnetic pulse measurement system based on FPGA is proposed. Monopole antenna is used to receive electrical signal, high-speed AD converter is used to sample voltage signal, and the sampled data can be received and saved into DDR2 and FLASH Memory by FPGA. The key technologies of signal conditioning, trigger mode, FPGA control and anti-interference are emphatically introduced. The performance and function of the electric field probe are tested by experiment. The sampled signals by electric field probe and oscilloscope are processed and compared by software. Research results show that the electric field of electromagnetic pulse measurement system has the characteristics of good linearity, small size, high noise immunity, and it can be used to measure the electric field of electromagnetic pulse with more than 2.5 ns rise time and 0-50 kV/m electric field intensity.