伪随机编码脉冲在UWB搜救雷达中的应用

【作者】 张双狮；

【导师】 祝忠明； 王绪本；

【作者基本信息】 成都理工大学 ， 计算机应用技术， 2006， 硕士

【摘要】 现代社会复杂多变，地震、山体房屋建筑坍塌、火灾、劫持绑架、恐怖主义时有发生，严重威胁着国家和人民的财产安全，更主要的是人民的生命安全。在这些城市灾害发生的时候，公安执法人员希望能对建筑物中的罪犯快速有效定位，相关搜救人员都希望能有一套有效手段，对困在建筑、浓烟、废墟中的人实现快速搜索定位解救。 成都理工大学地球探测重点实验室成功的研究了用声波震动搜救的方法并研制了救生仪器，在此基础上又探索用超宽带电磁方法作为探测手段实现救生，本论文就是国家自然科学基金项目《城市灾害救助生命搜索的超宽带电磁探测方法研究》中的一部分。 本文系统介绍了UWB搜救雷达系统的工作原理；发射信号时域特点、频域特点，并在此基础上研究了UWB搜救雷达信号的设计方法和信号的探测能力；系统介绍了伪随机编码脉冲信号的特点、脉冲压缩原理、脉冲压缩器的设计、子脉冲匹配滤波器的原理和设计方法，并在此基础上对伪随机编码脉冲压缩器和子脉冲匹配滤波器进行了仿真设计；研究了UWB雷达目标的宽带特性，针对城市灾害救助与生命搜索任务建立了探测仿真实验模型；最后在理论研究的基础上对所建立的信号模型、目标信息模型、探测模型进行了计算机仿真研究，得出了很好的结果。 首先，UWB短脉冲特性参数决定其穿透能力、横向分辨率和纵向分辨率、目标探测、成像、识别能力等；其次，利用伪随机编码方法调制短脉冲可以在保持子脉冲信号带宽的情况下，以低功率发射长脉冲串，而提高信号的能量，提高探测距离。模拟实验指出，缩短UWB子脉冲宽度可以提高信号的径向分别能力，而利用伪随机编码技术可以使UWB信号具有更强的探测能力，可以在回波信号功率水平远远小于噪声水平(如S／N=5％)的情况下实现对探测目标的高保真成像。更多还原

【Abstract】 It is more and more complex and changeable in modern society. Earthquakes, constructions、mountain bodies、 houses caving in, fire, kidnaps, terrorisms sometimes occur. All these are threatening national and people’s property security seriously, what is main is people’s safety. Occurs at these urban disasters, the public security law enforcement personnel hope that they can fast and effectively locate the criminals in buildings, the search and rescue personnel also hope that they can have a set of effective methods with which they can realizes fast search and localization to rescue person stranded in the thick smoke or the ruined constructions.Great successes have been achieved by the key laboratory of Earth Exploration in Chengdu University of Technology about the research of rescue method by sound wave vibration. What’s more, lifesaving instrument has been developed successfully by her. And in this foundation, researchers in the laboratory has begun to pay more attention to the realization lifesaving with the ultra-wide band electromagnetic method and has applied for the country natural sciences fund project "Survey of Ultra-wide band Electromagnetic Method for Urban Disaster Rescue and Life Searching" This paper is an important part of the project.The principle of work of the UWB search and rescue radar system has been introduced in the paper; The main characteristics of the transmitting signal waveform in time domain and frequency domain has been presented in it; design method of UWB search and rescue radar signal and the penetrability of the signal has been discussed in detail; The characteristics of the pseudo-random coded pulse signal has been studied, the pulse compression principle, the design of pulse compressor, the sub-pulse matched filter principle and the design method of it has been introduced, and in this foundation, the simulation design of the pseudo-random coded pulse compressors and the sub- pulse matched filter have been carried on PC; The wide band characteristics of the target of the UWB radar have been studied, more than that, the simulation experimental model in view of the city disaster rescue and the life search has been established.Good conclusions have been drawn based on the fundamental research and computer simulation of the signal model, the target information model, the survey model. First, the penetrability, crosswise resolution, longitudinal resolution, the ability of the target detection and the imagery of the UWB short pulse are decided by the characteristic parameters of it. Next, the short pulses modulated by the pseudo-random code enhance the signal energy更多还原