A. N. Novikov – Ph.D. (Eng.), Doctoral Candidate,

Military Academy of Strategic Rocket Troops n.a. Peter the Great (Balashikha)

E-mail: band31@mail.ru

The volumes of transmitted information in modern radio-electronic facilities dictate the need to move from narrowband signals to signals with a wide and super wide frequency band. Analysis of existing broadband radio electronic means has shown that they function on the basis of methods of correlation reception. However, saturation of modern megacities and industrialized regions with radioelectronic means leads to problems when receiving information based on these methods, which is due to the poor electromagnetic compatibility of radio electronic equipment. The methods of the time, frequency, and code division also almost exhausted their capabilities in the receiving and processing of broadband signals. In this regard, there is a need to develop a new approach to the receiving and processing of broadband signals.

One of the promising areas for receiving and processing of broadband signals is using of the methods of spatial selection in antenna arrays. These include the methods of adaptation, amplitude and phase resolution, as well as little-known methods of superresolution of Keipon and “thermal noise”. This is due to the fact that these methods make it possible to obtain an angular resolution for signal sources of a higher degree than determined by the dimensions of the antenna aperture in accordance with the Rayleigh criterion. However, at present, the problem of spatial processing based on the methods of superresolution has been solved only for narrowband signals.

The article is devoted to the development and investigation of the possibilities of quasi-optimal spatial direction finding of broadband signals based on the superresolution methods of Keipon and “thermal noise”.

For narrowband signals, this problem is solved by forming a direction-finding relief in the direction of the signal radiation. However, for broadband signals, it becomes necessary to form a direction-finding relief for all frequencies at which the signal acts. Thus, the difficulty of spatial direction finding of broadband signals based on the methods of superresolution is that the formation of the direction-finding relief in a given direction must be realized for an infinite number of frequencies of the broadband signal.

Based on the known relationships describing the direction-finding patterns formed by the antenna array when direction finding of narrow-band signals, the expressions have been obtained for optimal detection of broadband signals based on the methods of Keipon and “thermal noise”. However, the implementation of such an approach in practice is impossible because of the continuity of the signal spectrum and the infinity of computations.

To ensure the possibility of technical implementation of the superresolution methods for direction finding of broadband signals, it has been proposed to optimally form the direction-finding relief for the finite number of frequencies of the broadband signal spectrum. For the remaining frequencies of the signal spectrum, one should approximate using various functions.

The results of the simulation showed that the more frequencies of the signal spectrum in which the direction-finding relief is formed optimally and the higher the degree of the approximating function, the higher the accuracy of the direction-finding spectrum of the broadband signal. However, this also leads to an increase in hardware and time costs.

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