Research On High Precision Range Measure Based On Advanced Waveform

Range measurement with high precision provides a new approach for signatures extraction, recognition and tracking of radar targets in antimissile background. The purpose of this dissertation is to utilize phase ranging technology to improve measurement precision of radial range of targets based on exact measurement radars in existence. Aiming at Forward-Based Radar, process of phase-coded radar system is carried out by theoretic analysis and simulation test; and then discussing influence on extraction of Doppler phase ambiguity caused by random error; the boundary condition will be got to guide engineering application.In Chapter 1, it illustrates the background and significance of this dissertation, and introduces the present status of research on phase ranging technology. The problems exist currently are analyzed. The main content of this dissertation is also presented.In Chapter 2, the working process of phase-coded radar system is introduced. A new method of high precision range measurement for phase-coded signal is proposed. First, in the phase-coded radar system, matched filter of radar echoes is derived to obtain the range profile of continue pulses. Peak detection technology is performed to find adjacent sample point at peak position. After compensation, the phase of adjacent sample point is extracted, and the ambiguity measurement of Doppler phase is obtained. And then, velocity information measured by subsystem of Forward-Based Radar and time information recorded by clock are utilized to obtain integration of Doppler frequencies of pulses. Based on the previous information, we can solve the ambiguity of Doppler phase increment and get the phase cumulated range of target. Finally, simulation has confirmed its effectiveness and rationality. This method provides an applicable solution for phase ranging in the phase-coded signal system.In Chapter 3, performance analysis of phase ranging based on phase-coded signal is presented. We firstly derive the applicable boundary condition and constraints relationship of this method. Then, through the modular random error, a quantitative assessment about influence of each type of error on Doppler ambiguity phase extraction is presented. At last, the work flow of this method is summarized.The research work of this dissertation is concludes in Chapter 4 and prospective wok in the next steps is presented.