RANGE AND RADIAL VELOCITY MEASUREMENT AMBIGUITY ELIMINATION WITH TRAINS OF MULTICOMPONENT SIGNALS

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When designing pulse-Doppler radar, one of the key points is the choice of the pulse repetition period, which determines the boundaries of unambiguous measurement of range and radial velocity and creates contradictions in the measurement of these values. This contradiction is especially acute in the analysis of signals reflected from the propellers and turbines of aircraft. The main approaches to solving the problem of expanding the boundaries of unambiguous measurement of range and radial velocity is the use of variable pulse repetition period and the creation of signal ensembles to separate them by shape. Generation of an ensemble of sounding signals for a pulsed radar must be carried out taking into account both cross-correlation and auto-correlation properties. An approach to the generation of multicomponent signal trains with the possibility of pulse separation inside the train is proposed. Each of the pulses in the train is formed by adding a number of chirp signals, which differ in the values of amplitude and frequency deviation. As the frequency deviation increases, the amplitude of the component decreases. Reducing the cross-correlation coefficient of multicomponent signals from the formed ensemble can be achieved by increasing the number of components of each signal. The size of the signal ensemble, which can be formed on the basis of multicomponent chirp signals, depends on the requirements for the cross-correlation coefficient and auto-correlation function of the signals. It is shown that in order to expand the limits of coordinate measurement at a fixed wavelength, it is necessary to increase the number of pulses in the train. The results of the research demonstrate the potential possibility of using the proposed multicomponent chirp signal to form train of pulses with its subsequent separation.