On the basis of the analysis of the errors of the monopulse method of direction finding of the target of a radar station with a digital antenna array, a group of errors associated with fluctuations of the equisignal direction when scanning the beam of the antenna system, as well as with the non-identical shape of the generated beams of the monopulse group, was separated into a special cluster. This circumstance is especially critical for large-aperture radars with phased array with electric scanning, where the number of formed receiving beams is significant, in addition, the coordinates of the target usually do not coincide with the coordinate planes along which the coordinates are measured. The nonlinearity of this problem requires unique approaches and solutions. The classical formulation of the problem is associated with obtaining an estimate of the radiation vector of the entire antenna array from the known measured vector of complex signals at the output of the antenna array at a fixed time. To solve this problem and determine the decision rule, a neural network approach was used, while the neural network was trained according to the criterion of the minimum of the selected objective function. The substantiation of increasing the accuracy of measurements of angular coordinates in monopulse systems with scanning digital phased antenna arrays based on the use of neural networks in the process of radar data processing without the formation of direction finding characteristics is given. The results of modeling the characteristics of the antenna array (using the example of a flat antenna array with a dimension of 30 by 30 emitters) under the conditions adopted in the model of the antenna array of assumptions when implementing the classical and original methods are shown using examples of the surfaces of the variances of errors in measuring angular coordinates by the monopulse method in a rectangular spatial domain, which showed reduction of error and expansion of the measurement area. In the future, the practical implementation of this approach is assumed using FPGA in the receiving paths of the frequency-dependent part of the radio direction finder.

An algorithm of angular superresolution based on the Cholesky decomposition, which is a modification of the Capon algorithm, is proposed. It is shown that the proposed algorithm makes it possible to abandon the inversion of the covariance matrix of input signals. The proposed algorithm is compared with the Capon algorithm by the number of operations. It is established that the proposed algorithm, with a large dimension of the problem, provides some gain both when implemented on a single-threaded and multithreaded computer. Numerical estimates of the performance of the proposed and original algorithm using parallel computing technology CUDA NVidia are obtained. It is established that the proposed algorithm saves GPU computing resources and is able to solve the problem of constructing a spatial spectrum with an increase in the dimension of the covariance matrix of input signals by almost two times.

An algorithm is proposed for estimating the parameters of the antenna array radiation pattern with electric scanning in the observation coordinate system associated with the phasing direction of the antenna elements. It is shown that in this coordinate system, the concentration of coordinate lines near the phasing direction is maximal. This allows for a relatively small number of observation points to study in detail the parameters of the main beam and the first side lobes of the antenna array, as well as to evaluate the coefficient directivity. The simplest quadrature formula is acceptable for calculating the coefficient directivity in the selected observation coordinate system. The relations for calculating the antenna array radiation pattern taking into account the direction of the beam departures are given. It is shown that taking into account the directivity of individual elements during scanning leads to beam departures, which are convenient to track in the observation coordinate system. Procedures are proposed for estimating the beam width based on linear interpolation of sections of the radiation pattern where the level -3dB intersects. A procedure for estimating the level of side lobes is proposed, which does not include a procedure for searching the area of side lobes. The relations that establish the relationship between the observation coordinate system and the coordinate systems used in radar are given. The results of numerical studies that demonstrate the possibility of visualizing the radiation pattern and its cross-sections in the local coordinate system of the radar system, in the antenna coordinate system, and in the observation coordinate system are presented. This article is the first in a line of research in terms of determining the scientific and methodological apparatus for constructing adaptive algorithms for the diagram-forming scheme of the digital antenna array of radar stations and helps to determine the potential achievable characteristics of newly developed radar stations.

A method for suppressing pulse interference in adaptive antenna arrays is proposed, characterized by the use of a procedure for logical signal processing in the main and compensation channels to form a covariance interference matrix. To form the directional pattern of the main channel, weight coefficients are used to ensure a low level of side lobes. The radiation pattern of the compensation channel is obtained by subtracting the radiation patterns of orthogonal linear antenna arrays highlighted in the opening of the antenna array. Logical processing is used to determine the time domain, which does not contain a signal component, but contains external interference. It is shown that the use of logical processing of the main and compensation channels ensures the exclusion of the signal component from the covariance interference matrix and increases the noise immunity of the antenna.