Design And Impiementation Of CPPM Microwave Source For UWB Radar System

Ultra-wideband radar has the characteristics of anti-interference and highresolution. This article designs and implements CPPM microwave source forultra-wideband radar system. The CPPM signal is composed of pulse sequences.The time delay between pulse sequences varies chaotically and every pulse hasidentical width and amplitude. The correlation property and the bandwidth of thesignal depend on the chaotic characteristics and pulse-width, respectively.Logistic map is chosen as chaotic map by comparing the correlation propertiesof Tent map and Logistic map. At the same time, high-speed serial transceiver isproposed to decrease the pulse width. The CPPM signal based on Logistic mapis implemented by numeric simulation and FPGA, which owns pulse-width of0.64ns, bandwidth of1.56GHz and good correlation property. Ambiguityfunction shows that the signal has the advantages of high range and speedmeasuring precision and a good anti-interference ability. The CPPM signal isused as the signal source of radar system. And experimental results show that thesystem can accurately locate the position of the target, track the dynamic targettrajectory and detect the target through walls. The radar system can realizeprecise localization with double target resolution of16.5cm.This article designs and implements CPPM microwave source forultra-wideband radar system. Around the subject, the following work areperformed:1. This article introduces the advantages and disadvantages of thetraditional impulse radar and random signal radar. Combined with CPPMresearch status at home and abroad CPPM signal is introduced in ultra-wideband radar system to realize orientation of anti-jamming and high resolution.2. The article proposes to improve the signal bandwidth by reducing thepulse width of CPPM signal. Then, it introduces some narrow pulse technologieswhich are based on high-speed switching devices such as SRD and avalanchetransistor and digital logic gates. Also, it puts forward a new narrow pulsetechnology based on high-speed serial transceiver. At last, the working principleand the advantages and disadvantages of the mentioned four kind of narrowpulse circuit are analyzed.3. This article introduces the mechanism of CPPM signal. Thecharacteristics of two kinds of chaotic map are analyzed and compared: Tentmap and Logistic map. Broadband CPPM signal is realized with numericalsimulation and FPGA. And ambiguity function is used to analyze the feasibilityof ultra-wideband radar system based on CPPM signal.4. Ultra-wideband radar system based on broadband CPPM signal is builtand its performance is tested. Also, a series of experiments related to positioningand detection through wall are performed. Broadband CPPM signal generatedby FPGA is used as detection signal source. Combining with measuringtechnology of correlation, it locates the position of static target under differentdistance, tracks the trajectory of dynamic target, positions the people throughwall and images the target through wall.