This article introduces a bias controllable integrated optics electric field measurement system fabricated by LiNbO3 (LN) that can be used for the measurement of 10-kV/m subnanosecond rise time electromagnetic pulse (EMP). Combined with the structure of birefringence modulation (BRM) and the 1550-nm tunable laser, this probe has simple structure measures 1.5 cm $\times 2$ cm $\times4.5$ cm. It realized the set of bias to any value during $2\pi $ with less than 1-nm change of the wavelength of the tunable laser, despite the influence of the environment. Furthermore, an optimal bias automatic feedback controller based on Newton iteration algorithm is constructed to lock the bias at a fixed point. The statistical result (average ± standard deviation) of the bias under controlled is 90.4 ± 0.8°. Calibrated results show that it shows consistent response to the pulse with rise time of 200 ps, and the minimum and maximum measurement amplitude is 0.3 and 45 kV/m, respectively.

In high-altitude electromagnetic pulse (HEMP) field tests, coupling currents under a given illuminated electromagnetic field are important to the design of electronic systems and electromagnetic (EM) shielding. Compared to calculating the arithmetic average (AA) of the amplitude of coupling currents, reference field normalization (RFN) method is a data processing method of HEMP field tests studied in this article. In this method, a reference field is introduced and measured during each repeated illumination of the HEMP field test to minimize the impact of deviations of the illuminated EM field produced by a HEMP simulator. To evaluate the RFN method, uncertainty analysis is carried out. Then the uncertainty and relative error are calculated and compared between the RFN method and the AA method by the coupling currents data both from Monte Carlo method and real test. The results show that the RFN method has a better performance compared to the AA method both from the aspect of uncertainty and relative error.

When designing an electromagnetic enclosure, coupling electric fields under a given simulated high-altitude electromagnetic pulse (HEMP) field are commonly measured in HEMP field tests. Different from calculating the arithmetic average (AA) of the amplitude of the measurements, the reference field normalization (RFN) data processing method processes the measurements with the reference field to reduce the impact of deviations of the simulated HEMP field. This article mainly analysis the uncertainty of the coupling electric fields processed by the RFN method in HEMP field tests. The coupling electric fields data obtained from the Monte Carlo method and real test are used to compare the RFN method with the AA method. The uncertainty and relative error are then analyzed. The results show that the RFN method has better performance than the AA method.

A stochastic finite-difference time-domain approach for analyzing geometrical and media uncertainty is described. The proposed method can convert the geometry uncertainties into media uncertainties based on the conditional probability. It can solve 1-D, 2-D, and 3-D problems. In order to improve the accuracy of the method, the improved correlation coefficients related to space division are proposed. The proposed method and improved correlation coefficients are validated with simulations of both 1-D and 3-D stochastic scattering objects. The simulation results agree well with the results of the Monte Carlo (MC) method, while the computation time of this method is only about 2% of the time consumption of the MC method.

In system-level high-altitude electromagnetic pulse (HEMP) illumination tests, it is common to perform the test in two orthogonal polarizations of the incident electric field. With the judgment standard of the electromagnetic norm, this paper evaluated, improved, generalized, and verified this method. The evaluated result shows that the maximum error of the maximum coupling in this method is less than 3 dB. Meanwhile, this method is improved by serving the 1.2 period of the larger coupling of the 2 illuminations as the maximum coupling. The maximum error can be controlled within 1.5 dB. Moreover, this method is generalized to non-orthogonal conditions. Expressions of the deviations of this method are strictly derived. Based on this method, the application and some extended thinking are discussed. At last, a current coupling test is designed and carried out to verify the methods and conclusions. The methods introduced in this paper can be applied to any linear system in the illumination test under approximate transverse electromagnetic (TEM) waves.