Stability of Tracking the Delay of Phase-shift Keyed Signals with Spectrum Expanding in Synchronization Systems of Radio Engineering Systems

Abstract

The issues of ensuring the stability of delay tracking in synchronization systems of radio engineering systems when receiving phase-shift keyed signals with spectrum expansion based on pseudorandom sequences are considered. When working with moving objects, the delay of the received signal continuously changes, synchronization errors occur, and the quality of signal reception largely depends on the stability of the tracking scheme for the delay, characterized by the probability of tracking failure. Delay tracking is usually considered as the main task of the synchronization system of the considered radio systems with phase-manipulated signals with spectrum expansion based on pseudo-random sequences. The effect of synchronization errors when tracking the delay of a received phase-shift keyed signal with a spectrum extension based on pseudorandom sequences on the probability of tracking failure is studied. The calculation method is used to obtain families of dependences of the probability of tracking failure on the values of random and systematic components of the delay tracking error, normalized to the capture band of the time discriminator of the delay tracking scheme for various combinations of these parameters. The areas of weak and strong influence of the value of tracking errors over the delay of the received signal on the probability of tracking failure are determined. The nature of impact of random and systematic components of tracking error on the probability of failure of tracking was analyzed and it was found that in the General case is the ambiguity of normalized mean square of tracking error as the optimization criterion while minimizing the likelihood of tracking loss. Calculations performed for a wide range of changes in the normalized delay tracking errors show that to ensure a given quality of signal reception in a radio system with phase-shift keyed signals with spectrum expansion based on pseudorandom sequences, a joint choice of parameters of the delay tracking system that determine the value of random and systematic components of the tracking error is necessary. The results obtained can be used to analyze the characteristics of synchronization systems that monitor the parameters of received signals with a spectrum extension, and to justify the technical solutions of the synchronization system that provide the required quality of signal reception in information and measurement of radio-electronic systems.