A. A. Slobodyanenko1, V. S. Kulik2
1 Novosibirsk State Technical University (Novosibirsk, Russia)
2 Tomsk State University of Control Systems and Radioelectronics (Tomsk, Russia)

1 sepwood@gmail.com, 2 kulik_vs@mail.ru

The accuracy of determining the radiation pattern based on near-field measurements is directly related to measurement errors, among which systematic errors caused by the influence of the measuring antenna (probe) have the greatest impact. With increasing frequency, the results of determining the radiation pattern also begin to be affected by probe positioning errors, which require the development of high-precision scanners and specialized technological equipment with the possibility of precision alignment, which have a high cost of production. Therefore, it is extremely important to develop a more cost-effective approach, which consists not in eliminating, but correcting errors by introducing appropriate adjustments to the methods of processing and transforming near-field measurement results. The most promising among them is the source reconstruction method, in which the influence of the probe can be taken into account by generalizing the equations of the relationship between the sources and the measured fields.

Based on the rigorous equations of scattering theory, the equivalence theorem, and the reciprocity theorem, a new source reconstruction method has been proposed that takes into account the receiving characteristics and the position of the probe during near-field measurements. The effectiveness of the proposed method is achieved through the use of projection algorithms based on a sequential and randomized Kaczmarz procedure, which is experimentally confirmed by the example of a microstrip antenna array. The possibility of the source reconstruction method to eliminate the systematic measurement error associated with the influence of the probe has also been experimentally confirmed. The results of determining the radiation pattern with the modal decomposition method from the probe corrections according to the diagram are compared, demonstrating a higher accuracy of the proposed method.

Slobodyanenko A.A., Kulik V.S. Generalized source reconstruction method for near-field antenna measurements: theory and experiment. Antennas. 2026. № 1. P. 53–68. DOI: https://doi.org/10.18127/j03209601-202601-05 (in Russian)

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