Study On Pulse-Position-Modulated Pulse-Sequence Radar Signal Theory And Its Applications

In this dissertation, we systematically study the pulse-position-modulated pulse-sequence (PPM-PS) radar signal theory and its applications to radar/fuze systems. The main works include the analysis, generation and processing of PPM-PS radar signals, PPM-PS-based radar/fuze systems and key techniques of the radar/fuze system implementation. The main contribution includes the following aspects:1. We systematically analyze different types of uniform PPM-PS signals, including inter-pulse quasi-random binary coded PS signals, pulse-family quasi-random binary coded PS signals and pulse-family random binary coded PS signals. We give their definitions and mathematical representations, derive their spectra and ambiguity functions, plot the ambiguity figures and cut, and analyze their correlation properties and other performances. The results show that the pulse-family random binary coded PS signals perform best.2. We systematically analyze different types of random PPM-PS signals, including single random PPM-PS signals, compound PS (CPS) signals of the random PPM-PS and random binary coded pulse, and chaotic sequence-based PPM-PS signals. We give their definitions and mathematical representations, derive their spectra and ambiguity functions, plot the ambiguity figures and cuts, and analyze their correlation properties and other performances. The results show that the CPS signals have the thumbtack-typed ambiguity, no distance and/or speed ambiguity and excellent speed/distance measuring performances.3. We analyze anti-interference performances of the uniform PPM-PS radar signals and the random PPM-PS radar signals, and make the comparison between them. The results show that the CPS signals have low probability of interception and strong anti-interference ability.4. We thoroughly discuss the processing methods of the PPM PS signals. For the CPS signals, we propose a stochastically processing method to reduce distance side-lobe. We design and implement a generic high-speed real-time digital signal processing system using ADSP21060 processors, and introduce software and hardware design methods for the CPS signals.5. Based on the pulse Doppler radar/fuze systems, we propose and discuss the radar/fuzesystems using different types of the PPM-PS radar signals.6. We study the techniques of generating the PPM-PS signals and intermediate frequency (IF) sampling. We propose a chaos-based generation of the random PPM-PS signals, design and implement a generator of the PPM-PS signals. We introduce an IF sampling technique and simulate the performances of digital demodulation techniques of using Hilbert filters, Sine filters, Bessel filters and poly-phase filters. The poly-phase filtering method can achieve the higher mirror-frequency rejection ratio by using the low order filters.