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TEM cells that are popular in immunity measurements require high operating power. In this paper, an immunity testing cell using a rectangular loop resonator is proposed. The testing cell is expected to generate high electric field strength at comparatively low power. The resonator comprises a conducting channel plate and a capacitive gap set onto the ground plane. The testing cell has a size of 1/10 wavelength at the testing frequency and therefore is suitable for immunity testing at low frequency. In this study, the electric and magnetic field distribution inside two different types of proposed resonators are analyzed by the FDTD method. Comparison of analytical and experimental results shows a close match. The electric field strength inside the two resonator types is increased by 31.2 and 14.3 dB, respectively, relative to that of the TEM cell of similar size. In the latter type of resonator the electric field deviation inside a square area of 100 mm length is suppressed to 2 dB. Moreover, the resonator covered with a shield case for practical use shows an increase of 11.2 dB in the electric field strength over the level of the similar size TEM cell. The amplitude deviation remains the same as that of the bare resonator. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 86(7): 22–30, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10011 [ABSTRACT FROM AUTHOR]

In the radiation immunity test for telecommunication equipment, an electromagnetic applicator such as chamber, a transmission electron microscopy (TEM) cell and a general transmission electron microscopy (GTEM) cell are used. Characteristics that include a semianechoic uniformity of the electromagnetic field without a device under test have been evaluated. However, characteristics that include an electromagnetic field in the presence of the device under test have not been reported. In this paper, it is recognized that these electromagentic application are designed in such a way that they can generate an electromagnetic field distribution generated by the plane wave incident on a conducting sphere, the electric field is evaluated and compared in the case in which the device under test is placed within the application. Further, evaluation results are include for the size of the device under test for which the immunity test is possible in each applicator. The evaluation method first derives the theoretical value of the scattered electric field when a plane wave is incident on the conducting sphere in free space. Next , these theoretical values are compared with the measured electric field values around the conducting sphere in each electromagnetic applicator. It was found that the difference between the measured and the theoretical results is the smallest and the frequency dependence is the lowest in a semianechoic chamber. In the case of a TEM cell and a GTEM cell, it was found that the difference between the measured and the theoritical values is less than +6 dB if the magnitude of the device under test is less than one-third the spacing between the inner and outer conductors. [ABSTRACT FROM AUTHOR]