Correction Method for Measurement of EUT with Dipole Antenna in GTM Cell
Gigahertz transverse electromagnetic (GTEM) cell is a promising alternative way to implement electromagnetic interference (EMI) and electromagnetic susceptibility (EMS) measurements for small transceivers due to its significant advantages on small space and low cost. However, different with full-wave anechoic chamber, only one wave absorption wall is setup in the GTEM cell at the opposite side of input port, a tapered waveguide cavity structure is used to produce uniformly distributed transverse field, that would raise another issue: coupling effect between the antenna under test (AUT) and the structure of GTEM cell. The effect of impedance deviation of AUT is studied in this paper, a formula to calculate the impedance of AUT under coupling situation is deduced. By using the model proposed in this paper, the transmission power reduction of equipment under test (EUT) due to the impedance mismatch caused by coupling issue can be numerically calculated, and result to more accurate measurement result.
KeywordsGigahertz transverse electromagnetic (GTEM) cell Coupling Input impedance Dipole antenna
This work was supported by National Natural Science Foundation of China (No. 61427801 and No. 61601040), Scientific and Research Innovation Program of BUPT (No. 2016RC02), 111 project (No. B17007) and Director Funds of Beijing Key Laboratory of Network System Architecture and Convergence.
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