The article introduces modernizing the global approximation method of the posterior probability density function in the implementation of phase-locked loop algorithms which improves the accuracy of clock synchronization in telecommunication networks, and reduces the time of entering into synchronism. Keywords: clock synchronization; phase-locked loop; the global approximation; filtering; synchronism.Citation: Ryabov A.V., Fedyunin P.A., Presnyakov M.Y. Modernizing the global approximation method of posterior probability density for oscillator synchronization purposes,