EFFECT OF PHASE INSTABILITY OF GENERATORS ON THE OPERATING PARAMETERS OF A CARRIER FREQUENCY SYNCHRONIZATION SYSTEM AGAINST A BACKGROUND OF ADDITIVE GAUSSIAN NOISE AND A DOPPLER FREQUENCY SHIFT

Abstract

The article deals with the systems of phase synchronization of radio engineering devices of communication technology. The purpose of the article is theoretical research in the direction of development, analysis and improvement of known and synthesis of new phase synchronization circuits, characterized by high noise immunity, accuracy and speed with simplicity of design. The problem is solved to investigate the possibilities of closed and combined synchronization systems for operation under conditions of phase instability of generators in a communication channel against the background of external additive Gaussian noise and Doppler frequency shift. The following results were obtained. The analysis of closed-type synchronization systems during operation under the conditions of phase instability of generators is carried out and its inconsistency is shown in order to minimize the phase error variance and increase the dynamics during carrier frequency monitoring. The process of synthesis of open communication in the combined synchronization system is refined and analytical dependences are offered, which allow to refine the technique of synthesis of open communication for the combined synchronization system with regard to the phase instability of the generators against the background of the influence of the adducts. Conclusions. Increasing the noise bandwidth of the proportional-integrating filter of the closed-loop phase-in-phase synchronization system to the parameters of the ideal filter impairs the dynamics of the specified system. For the combined synchronization system, in the conditions of phase instability of the generators, an increase in the noise bandwidth of the input signal can be achieved by applying a closed-loop proportional-integrating filter and by making appropriate selection of parameters of the transfer function of the link of the open channel. In the conditions of phase instability of the generators in the combined system of synchronization by selecting the parameters of the proportional-integrating filter, it is possible to provide the necessary dynamics of the system and to achieve the optimal value of the dispersion of the phase error in it. Taking into account Doppler noise under conditions of phase instability of generators for a closed-type synchronization system and a combined synchronization system requires a reduction of the optimal value of the noise bandwidth.