Wang Qingguo

Comparative analysis on the fast rising edge pulse source with two kinds of avalanche transistor

A fast rising edge pulse can be generated by Marx circuit based on avalanche transistors. The avalanche principle of a Marx circuit is analysed. and the triggering circuit and ten stages Marx circuit board are designed. A series of negative pulses with falling edge time about 2ns,voltage amplitude from about 700V to 1600V and pulse width below 6ns are obtained when the Marx circuit is ten stages based on the FMMT415 and FMMT417 by changing the charging voltage and the capacity. The pulse waveforms based two kinds of avalanche transistors are compared. The results are that a higher peak pulse can be get based on the FMMT417 than the FMMT415, the peak value will be lager when the charging voltage is higher, and pulse-width will be lager when the capacities are bigger within a certain limit.

Optimization of Calibration Procedure for Reverberation Chamber Based on NI LabVIEW Platform

As an alternative technique, reverberation chamber has been more and more accepted and applied for EMC test, especially for EMS tests for electronic equipment, ordnance electronics and also advanced MIMO technologies for wireless communication. In this paper, the test standards are first analyzed and compared. Secondly, by considering the economy and time saving factors, an optimized programming procedure and program structure are designed and presented for realizing the calibration test based on NI LabVIEW platform. Finally, some experimental results for a newly built reverberation chamber are presented.

Study of the formation and attenuation laws for electromagnetic pulse filed in the RC

The field build up process of the electromagnetic pulse in the reverberation chamber(RC) is analyzed. The field built up by the pulses of different peak, rising time, and duration in the reverberation chamber has been studied. The analysis results show that the change of parameters will directly result in changes in the input power and impact on the field in the reverberation chamber. Higher peak values and duration time of the pulse signal will increase the input power, and the ensemble maximum of the field becomes larger. On the contrary, longer rise time will reduce the input power so that more time needed to reach the ensemble maximum value and the forefront of the field waveform becomes gentle, and peak values decrease. Moreover, time domain expressions of the electric field in the reverberation chamber are derived, providing theoretical support to electromagnetic pulse protection test method in the reverberation chamber.