一种小型脉冲场探头校准装置研究

A Study on Small Pulse Field Probe Calibration Device

横电磁波(TEM)小室是一种常用的电磁场发生装置。文中设计了一种脉冲场探头校准用的两端呈锥形过渡段、外导体两侧开放式的TEM小室。通过分析被校准电场传感器探头尺寸、TEM小室特性阻抗等需求,优化设计了TEM小室的高度和宽度。通过频谱分析计算电磁脉冲能量占比的频率分布,确定TEM小室的频率需求,并分析了在0 MHz~300 MHz频率范围内TEM小室的电压驻波比和S参数,以及场分布的均匀性和场波形。通过试验验证,证实了所设计的TEM小室反射小于-17 dB,插入损耗小于1 dB,加载脉冲源后场波形满足脉冲场探头校准的需求。

Transverse electric and magnetic field(TEM)cell is a commonly used electromagnetic field generator.In this paper,a TEM cell with two tapered transition sections and two open outer conductors for pulse field probe calibration is designed.The height and width of the TEM cell are optimized according to the requirements of the probe size of the calibrated electric field sensor and the characteristic impedance of the TEM cell.The frequency requirement of the TEM cell is determined by calculating the frequency distribution of the electromagnetic pulse energy proportion through spectral analysis.The voltage standing wave ratio and S-parameters of the TEM cell are analyzed in the frequency range from 0 MHz to 300 MHz.Uniformity of field distribution and field waveform are also analyzed.It is verified by experiments that the proposed TEM cell reflection is less than-17 dB,the insertion loss is less than 1 dB,the waveform of the loaded pulse source can meet the calibration requirements of the pulse field probe.