L.I. Averina1, A.Yu. Lafitskiy2, D.Yu. Charkin3

1−3 JSC «Concern «Sozvezdie» (Voronez, Russia)

The problem of adaptive beamforming in radio communication devices based on digital antenna arrays is one of the key ones provided they function in an electromagnetic environment. This issue has been theoretically investigated in detail for various criteria of optimality. However, in practical implementation, due to the inaccuracy of the calibration of the antenna array channels, the error in determining the direction of arrival of the useful signal, distortion of the partial diagrams of antenna elements and other destabilizing factors, the effectiveness of the developed methods is significantly reduced. At first in this article a simulation modeling is used to analyze the influence of various system errors on the parameters and characteristics of a radio modem based on a ring antenna array which implements MMSE and GCS spatial filtering methods. At the same time a regularized form of the GSC method is considered to increase its stability. Then the LMS algorithm is used to determine the main advantages and disadvantages of these methods of adaptive beamforming. Finally, a block diagram of the robust combined method of space-time signal processing is proposed, which makes it possible to effectively compensate for both additive interference of various types and multiplicative ones arising from multipath signal propagation. On the basis of simulation and experiment, it is shown that the proposed combined algorithm for adaptive beamforming of a multichannel system allows a radio modem based on a digital antenna array to function with satisfactory efficiency in a complex electromagnetic environment in the presence of system errors.

Averina L.I., Lafitskiy A.Yu., Charkin D.Yu. Aspects of practical implementation of space-time signal processing in adaptive antenna arrays in a complex electromagnetic environment. Radiotekhnika. 2022. V. 86. № 1. P. 81−92. DOI: https://doi.org/10.18127/j00338486-202201-13 (In Russian)

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