THE INFLUENCE OF STATISTICAL CHARACTERISTICS OF THE FLUCTUATIONS OF THE RADIATION SIGNAL INITIAL PHASES ON THE ACCURACY OF THE MEASUREMENT AERODYNAMIC OBJECT RADIAL VELOCITY

Abstract

The article deals with the estimation of radial velocity when using a coherent packet of radio pulses regarding the case of the presence of correlated fluctuations of the initial phases in the reflected from the aerodynamic object pulses. The subject of the research is the accuracy of measuring the frequency of the received packet for the case of concerted processing without taking into account the phase fluctuations of its radio pulses. The purpose is a numerical analysis of the influence of the statistical characteristics of the fluctuations of the received pack’s initial phases on the decrease in the accuracy of measuring the radial velocity of the aerodynamic object. The task: to estimate the possible values of fluctuation constituent middling quadratic error of measuring of radial speed of aerodynamic object. Consideration is given to the assumption that an additive mixture of deflected signal and uncorrelated Gaussian noise is input to the radar receiver. It is considered that the phase fluctuations of the received packet are distributed according to the normal law with zero mean, and the correlation of phase fluctuations with the increase of the interval between the packet radio pulses decreases according to the alternating law. Methods used: methods of probability theory and mathematical statistics. The following results are obtained: the accuracy of frequency measurement of the pack had been estimated in the presence of correlated phase fluctuations of its radio pulses. Conclusions. The results indicate that for modern radars in the conditions of regular measurement the accuracy of estimating the frequency of the packet of radio pulses is much more influenced by the statistical characteristics of the phase fluctuation than the signal-to-noise ratio. Due to the phase fluctuations of the radio pulses of the received packet, the mean-square error (MSE) of radial velocity measurement of the aerodynamic object is able to exceed the values determined by the requirements for coherent pulse radar.

Keywords

• coherent pulse radar
• packet of radio pulses
• phase fluctuations
• radial velocity aerodynamic object
• Gaussian noise
• radar surveillance