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4 Literature review and problem statementMost radio electronic systems operate under conditions of complex electromagnetic environment. An essential (and sometimes the only one) disturbing factor in practice is a multicomponent additive interference. Methods and means for suppressing multi-component interferences attract at present much attention from specialists. Paper [1] describes a method for the suppression of such interferences based on a polynomial approximation of the phase and subsequent use of the phase information. Applying only one parameter narrows the range of interference situations for which a given method can be employed. Articles [2,3] explore the possibility of nonlinear processing of an additive mixture of signal and a two-component interference in order to build the receiver, optimal for the criterion of maximum likelihood. The results of the studies outline a general approach to solving the problem, without providing for a direct numerical validation. The case when a source of a multicomponent interference is dispersed in space was considered in paper 4  O. Ananieva, M. Babaiev

particularly unacceptable where a communication system is integrated into the overall system of a technological process safety system. The described situation occurs specifically during railroad transportation in the technological communication systems and subsystems that transfer signals from railroad automatics. As the saturation of industries, transport, and even households, with such integrated systems grows, solving the tasks on noise-resistant receival of information signals becomes increasingly relevant. Literature review and problem statementDecreasing the influence of multicomponent interference on the results of reception of information signals has attracted undiminished attention of specialists. Paper [1] reports

In connection with electromagnetic interference influence on the track circuits, the purpose of the research is finding the means to increase the noise immunity of an audio frequency track circuit. The authors propose a new engineering solution, which enables reducing the effect of noises on the input of the track receiver in the intervals between signal current pulses. The proposed noise-immune audio frequency track circuit is based on inserting a delay line, an adjustable single-pulse generator and a controlled electronic switch into the existing audio frequency track circuit equipment. To analyze its efficiency, the operation of the audio frequency track circuit was simulated under conditions of traction current disturbances, impulse and fluctuation interferences with the known parameters. The results show that proposed device for railway transport allows to increase a signal-to-noise ratio on the track receiver input from 8% to 30%, depending on the interference parameters and the level of the useful signal.

An optimal receiving device for information signals of tonal rail circuits has been synthesized. The signals are observed against the background of an additive five-component interference. The first component of the interference is broadband Gaussian noise. The other four components of the interference are structurally determined: single impulse interference, interference from an adjacent tonal rail circuit, and multiharmonic interference from alternating traction current combined with the power line and from the locomotive traction converter. The presence of a complex of interference leads to errors in decision-making regarding the regulation of train traffic. This puts the participants in this movement before the danger of threatening emergencies. Therefore, it is necessary to develop and study means of noise-immune reception of information signals and the formation of dispatch decisions. The decision on the presence or absence of a signal is made by comparing two values of the mean square of the approximation error. This error is understood as the difference between the input voltage of the receiver and the sum of the signal with structurally determined interference. The first value of the error is calculated assuming the presence of a signal in a mixture with structurally determined noise. The second error value is calculated on the assumption that there is no signal in this mixture. The noise component is assumed to be present in both cases. The solution corresponds to a channel with a lower mean squared error. The block diagram of the device is presented. Analytically, it has been shown that the average value of the error in recognizing situations of presence or absence of a signal is two orders of magnitude less than the admissible value according to regulatory requirements. High noise immunity of the developed device will improve the safety of train traffic