E.A. Ishchenko1, V.V. Negrobov2, Yu.G. Pasternak3, V.A. Pendyurin4, S.M. Fedorov5

1,3,5 Voronezh State Technical University (Voronezh, Russia)

2 Joint Stock Company "Scientific Design and Technology Bureau "Ferrite"(Voronezh, Russia)

4 Joint Stock Company Scientific and Production Enterprise "Automated Communication Systems"(Voronezh, Russia)

1 kursk1998@yandex.ru, 2 negrobov_VV@mail.ru, 3 pasternakyg@mail.ru, 4 pva777777@yandex.ru, 5 fedorov_sm@mail.ru

The structure of the received electromagnetic field is strongly influenced by scatterers (for example, the body of the device) located in close proximity to the receiving antenna, which leads to a drop in the quality of communication. This problem can be solved with the help of calibration, but it is an expensive procedure and cannot take into ac-count all possible diffuser configurations in real practice.

In this paper, we study the possibility of using methods for the formation of "virtual" antenna arrays based on the use of the quasi-solution procedure when calculating the amplitudes of auxiliary sources in order to predict the structure of the electromagnetic field near the mobile phone and the user's body.

It is shown that the use of these methods can improve the accuracy of determining the direction to the source of radio emission, as well as the calculation of phases at various points in space in the plane of the antenna array of a mobile phone. These "virtual" phase readings can be interpreted, among other things, as additional "virtual" receiving channels, in addition to the real ones. The article presents frequency dependences of bearings at different radii for virtual and real antenna arrays, dependences of absolute direction-finding errors, as well as phase values of the electric field component on a circle of various radii.

Based on all the studies carried out, it can be concluded that the described methods are promising and that they need further research in order to find the optimal values of the initial conditions necessary to solve the problem of choosing the number of auxiliary sources, as well as to minimize the objective function. One of the key areas of ap-plication of the results obtained is modern radio engineering systems, which are necessary for improving the hardware and software designed to receive and process ultra-wideband signals. These include military and special purpose systems such as radar, radio direction finding, radio navigation, communications and telecommunications, as well as civil portable tele-communications equipment (mobile phones, Internet access radio modems, personal computers).

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