Aslanov

Influence of harmonic noise on phase-lock loop (PLL) leads to distortion of received information and a loss of PLL stability. This article analyzes effects of harmonic interference on synchronization processes in the second order PLL system. Analysis of signal grabbing and interference capturing cases was carried out in this work; projections of a phase path onto planes, which illustrate the specified modes, were also obtained. By analyzing phase planes, equations of capturing signal and interference were obtained. Dependence diagrams of the signal-to-noise ratio and frequency error are presented along with a bifurcation diagram. Application compares critical values ​​of the PLL parameters obtained by different methods.

Effect of a harmonic interferer on phase-lock results in distortion of information received in input signals, and in the loss of stability of the phase-lock. The authors consider the influence of harmonic interference on synchronization processes in the first-order loop. Also the paper presents an analysis of cases of signal capture and the capture of the disturbance in the phase-lock.

A comparative analysis of statistical characteristics of phase locked loop was carried out, when harmonic interference along with noise influences on its entrance. As the result of solving of Fokker-Planck-Kolmogorov equation (FPK), the probability density function (PDF) of the error signal, the average time until loss of synchronization and the probability of skipped cycle were obtained. The comparison of two approaches of obtaining of statistical characteristic was carried out.

Average time before tracking loss and average value of frequency disagreement of phase lock loop were considered when adaptive combination of signal, harmonic interference and noise was received as an input signal.