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ANALYSIS OF SIGNAL PROCESSING METHODS IN MIMO SYSTEMS

Conflicts of the last decades (the Chechen war (Russian Federation), armed confrontation in the countries of the Middle East and North Africa, anti-terrorist operation in the territory of Donetsk and Lugansk regions (Operation of the United Nations)) go beyond the existing (traditional) forms and methods of warfare, conducted on the background of information and psychological operations and the active using of electronic emitters. Therefore, provision of sustainable communication is one of the priority directions of scientific research. One of the directions of increasing the noise immunity of radio communication devices is using of the multi-antenna radio communication systems. However, they are complex technical systems. There are many approaches to increase the impedance of multi-antenna systems, but the authors of this article limited themselves to considering only the methods of signal processing, namely orthogonal spatial-temporal codes. During the study, the authors used the basic provisions of the theory of communication, the theory of antennas, the theory of noise protection and signal-code structures. In the course of the analysis, the authors found, that the computational complexity of the orthogonal codes used in MIMO systems is directly proportional to the number of transmitting antennas in the system, which leads to a linear increase in the number of computational operations in the processing of signals was using mentioned spatio-temporal codes. However, this type of spatial-temporal codes has high energy efficiency in MIMO systems with a small number of antennas. The authors propose to develop a method of space-time coding of signals in multi-antenna radio systems with high energy and spectral efficiency, when the proposed method had an acceptable computational complexity.