Research On Feature Extraction For Target With Micro-motion Based On Radar Phase Derived Range

Radar signature of targets with micro-motion is becoming a hot research aspect in recent years. One of the bottlenecks of radar signature extraction from targets with micro-motion is the demand of ability of ranging and measuring radial velocity high-precisely. With the background of this demand, this dissertation addresses phase derived range technology, and the method of micro-motion signature extraction under this technology.In chapter 1, it introduces the background and significance of this dissertation at first. Secondly, it summarizes the characteristics of phase derived range technology and micro-motion signature extraction, and introduces the domestic and abroad research status recently, and the advantages of this technology in micro-motion signature extraction and the achievements of the U.S.A in this area are highlighted. At last, the main content and structure of this dissertation are also presented.In chapter 2, phase derived range technology based on wideband radar has been analyzed mainly. It illustrates the principle of range vernier technology in detail firstly. Secondly, it deduces a phase derived range method based on wideband Linear Frequency Modulation signal. Ambiguous Doppler phases are extracted by measuring and compensating peak phase, then, a method of delta-phase ambiguity resolution using velocity measurement is proposed. It obtains the radial range increment by changing the sum of delta-phases between successive pulses. Finally, the previous condition of delta-phase ambiguity resolution is deduced, giving the constraints of radar measurement ability and radar system parameters. Simulation experiments focus on the ranging errors under different conditions whether delta-phase ambiguity resolution correctly or not, and verify the theoretical derivation is correct.In chapter 3, radar signature extraction of targets with micro-motion based on wideband radar phased derived range has been analyzed mainly. At first, the narrowband radar echo model of micro-motion target is presented, and it applies range vernier technology to obtain precise range measurements, estimates the micro-motion parameters using linear FM basis decomposition under special scene. Secondly, the wideband LFM signal echo model of micro-motion target is presented, and it applies wideband signal phase derived range technology to measure different scattering points'precise range measurements, estimates the micro-motion parameters of each scattering point separately using the same way. At last, the delta-phase ambiguity resolution method of micro-motion targets is analyzed, and a method of ambiguity resolution using bulk Doppler and micro Doppler integral is proposed, then, deduced the condition whether micro-motion can be ignored. Simulation experiments verify the correctness of condition, and analyze the range measurement ability separately under correct ambiguity resolution results and faulty results.In chapter 4, it presents a summary of the full dissertation, points out the main work and innovations, in particular, proposes some suggestions and ideas for the further study and research.