Development of a device for the optimal reception of signals against the background of an additive three-component interference

We have synthesized the optimal receiver of code signals from an automated locomotive signaling system. The signals are observed against the background of a three-component additive interference. The first component of the interference is pulse, the second component is a continuous sinusoidal disturbance from a power line, the third component is the Gaussian noise. We have implemented a method of joint evaluation of signal parameters and the structurally deterministic interference in the receiver. The proposed method is flexible to the changing parameters of interference. A decision on the form of the received code signal is made based on the criterion of a minimum in the mean square of approximation error. The error of approximation means a difference between the magnitude of the sum of a signal and the structurally deterministic interference components and the magnitude of total voltage at a receiver’s input. It has been shown, based on realistic assumptions about the statistical relationships between a signal and the interference components, that the objective function is a sum of the isolated logarithms from the ratios of likelihood and correction functions, taken with an opposite sign. This research has focused primarily on studying a possibility to reduce the impact of structurally deterministic interference. The result is the designed device capable to respond quickly to changes in the parameters of such an interference. We have shown a fundamental possibility to construct an optimal receiver in a modular fashion. In this case, modules can be connected and disconnected according to the a priori defined composition of the interference set, while the «library» of modules can be updated when the new kinds of interference emerge. It has been shown through computer simulation that in the channel, responsible for forming a valid solution, the magnitude of approximation error is about 6 times less than in the other two channels. This ratio holds when the amplitudes of a pulse noise and an interference from a power line have a multiple advantage over the amplitude of the code signal. The designed device ensures high noise immunity when distinguishing code signals over a wide range of interference parameters. This would make it possible to improve the safety of motion, as well as accuracy in keeping the schedule of trains