I. P. Kovalyov1, N. I. Kuzikova2
1, 2 Nizhny Novgorod State Technical University n.a. R.E. Alekseev (Nizhny Novgorod, Russia)

The task of constructing an electrically small surface antenna for a MIMO communication system is set in this work. The dimensions of the device and the antenna are considered to be small compared to the wavelength. Initially, it is assumed that the metal case of the device has the shape of a sphere and for analysis the electromagnetic field is represented by the sum of the fields of spherical waves.

It has been shown that an arbitrary electromagnetic field on an electrically small sphere is determined by three independent coefficients and, accordingly, there are three spatial channels in the MIMO system. Three channels are formed when measuring three components of the magnetic field on the surface of the metal housing. A reliable assumption is made that the results of the analysis of the surface antenna on the sphere are transferred to a surface of a different shape. Sketches of three-channel antennas have been given.

Kovalyov I.P., Kuzikova N.I. Small-sized surface antenna for multipath radio channels. Antennas. 2022. № 4. P. 18–25. DOI: https://doi.org/10.18127/j03209601-202204-02 (in Russian)

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