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PROVIDING INCREASED REQUIREMENTS FOR TIME SYNCHRONIZATION QUALITY UNDER GNSS VULNERABILITIES

In different industries, it is increasingly necessary to provide consumers with accurate timing and frequency signals.The most common source of accurate time synchronization signals in Ukraine is GPS, but they are vulnerable to a variety of deliberate and unintentional obstacles, which does not ensure high reliability of delivery of accurate time synchronization signals to consumers. One promising solution to the problem is to receive an exact time signal from the national time benchmark. National time benchmarks can be used as a backup source of accurate time synchronization in the implementation of the 5g mobile standard, as only they outside the mobile synchronization network have the accuracy required for 5g
 The article is devoted to the problems of creating networks in the face of increasing quality requirements to time and frequency synchronization in industries that are critical to time accuracy. The paper presents a comparative analysis of the requirements to time synchronization accuracy in various industries of strategic importance for the country. Ways of delivering accurate time signals from national time standards in the context of GNSS vulnerability are considered, an examples of technical solutions for delivering accurate time signals to remote users based on current ITU-T and IEEE recommendations are provided. These technical solutions can be successfully taken into account for the development and modernization of the Time Synchronization and Reference Frequencies Service. Solutions to the problem of synchronization signals delivery from national frequency and time standards to users, based on modern PTP IEEE 1588-2008 equipment are considered. The main factors that negatively affect the accuracy of the time synchronization networks constructed in accordance with the PTP 1588-2008 protocol are considered, and recommendations are given to minimize their impact.