摘要 : The paper is devoted to the problem on synthesis of the optimal pilot component phase tracking algorithm of L1OC advanced signal of the GLONASS satellite navigation system with processing on the subcarrier frequencies. The authors... 展开 The paper is devoted to the problem on synthesis of the optimal pilot component phase tracking algorithm of L1OC advanced signal of the GLONASS satellite navigation system with processing on the subcarrier frequencies. The authors present a brief description of the advanced open access signal with L1OC GLONASS code division, which includes the pilot and information components. The pilot component of the signal has a BOC(1,1) modulation (binary offset carrier), while the information component has a BPSK(1) modulation (binary phase shift keying). The authors consider the mathematical formulation of the problem on synthesis of an algorithm for tracking the phase of the signal, which extracts the information only from the L1OC pilot signal component. The authors present the equations describing the evolution of the posteriori probability density of the estimated state vector, showing the phase change of the signal in the space of states, as well as the equations of quasi-optimal filtering of the given state vector that is based on a Gaussian approximation of the posterior probability density. A representation of the equations of quasi-optimal filtering is presented in the form of a tracking system, comprising of a phase discriminator, which smoothes filter, and a reference signal generator. Paper presents a block diagram of the synthesized phase discriminator. It is shown that the phase discriminator with the processing of the L1OC pilot signal component on subcarrier frequencies has a structure, different from that of the classical phase discriminator processed on the carrier frequency. The calculation of the statistical characteristics of the correlators, used in the subcarrier frequencies processing algorithms, is carried out. The authors obtained the expressions for discriminatory and fluctuating characteristics of the synthesized phase discriminator and presented the results from the analysis of concerned characteristics, which suggest that discriminatory characteristic has a point of stable equilibrium. The results of the comparative analysis between the characteristics of the synthesized phase discriminator and the similar characteristics of the classic phase discriminator are presented; the latter relates to the phase tracking system over the L1OC pilot signal component on the carrier frequency. The authors describe averaging technique for the dispersion equations of the synthesized quasi-optimal filtering algorithm, and present corresponding averaged dispersion equations, which do not depend on the random input signals and assessments, and allow one to build a system for tracking the phase of a signal with constant coefficients (stationary tracking system). The authors present computer simulation results of the synthesized tracking system. Various models of the signal phase change are considered, including those in a form of a random process and a highly dynamic quasi deterministic process involving intense spurts over the line of sighting. The authors also consider the options for simulating a quasi-optimal tracking system for a phase of a signal with variable and constant parameters. 收起