【作者】 冯聃；

【导师】 杨士中；

【作者基本信息】 重庆大学 ， 电路与系统， 2003， 硕士

【摘要】 随着高速公路的迅速发展，防止汽车相撞已引起了世界各国的广泛关注，因此急需找到一种能有效解决汽车碰撞问题的方法。针对这一现状，本文介绍了一种高速公路汽车防撞雷达系统。该防撞雷达系统主要是用于高速公路上多雾天气防止车辆前后追尾相撞，而不考虑车辆与其前方的非车辆障碍物之间的防撞问题，设计只完成最基本的险情探测和预警功能的前视防撞雷达。工作于C频段，收发一体，具有结构简单、体积小、重量轻的特点。 本文结合大量的框图、电路图、波形图，详细阐述了高速公路汽车防撞雷达的系统结构、工作原理、工作流程。并根据信号的工作频段和各分机电路的主要功能，将整机系统分为射频信道、中频调制解调和终端处理三大部分。对实现系统的各部分电路及终端的信号处理方法作了较为详细的介绍。重点分析了防撞雷达的射频信道部分。给出了射频信道各部分组成框图、系统的主要技术指标及各参数选取的考虑。对射频信道链路及测距精度进行了详细的分析和计算，给出了理论计算结果、讨论了影响测距精度的几个因素。探讨了汽车防撞雷达的电磁兼容性问题，提出了解决电磁兼容性问题的几种措施。研究了射频信道中的自动增益控制(AGC)技术。另外对系统的双工体制及天馈线也进行了分析和讨论。本雷达系统的甲机信道是一个典型的C频段无线通信系统收发信道，配合适当的终端设备，可用于容量相当的通信系统及测控系统。而乙机信道是一个无人职守的转发器信道，除了直接可用于接力通信系统中外，如果增添适当终端设备还可构成具有遥控功能的数据报告平台，论文给出了本防撞雷达射频信道应用在其它系统中的实例。 最后本文对射频信道的主要指标进行了测试，给出了测试结果。根据测试结果，对本文提出的高速公路汽车防撞雷达系统存在的问题提出了改进意见和措施，对未来更高阶段的汽车防撞雷达的发展趋势做了展望。更多还原

【Abstract】 With the rapid development of the expressway, automobile anti-collision has been received considerable attention all over the world. So it is essential to find out an effective way to solve the automobile anti-collision. This paper introduces an automobile anti-collision radar system on the expressway. The automobile anti-collision radar is mainly applied to prevent the vehicle from colliding back and force under the fog weather condition with no consideration of the other obstacle’s anti-collision before the vehicle. It is only designed to achieve its basic application of danger condition detecting and collision warning. The anti-collision radar works in the C frequency band which has some features such as simple architecture, small volume and light weight.With the illustrations of many block diagrams, circuit schematics and waveform figures, this paper expatiates the system architecture, working principle and working flow of the expressway automobile anti-collision radar. The whole system is divided into three parts according to the signal frequency, i.e., RF channel, IF modulation and demodulation,digital terminal. This paper particularly introduces each circuit schematics and terminal signal processing methods. The radio frequency channel is analyzed in detail. The paper gives the structure block diagrams, main technology parameters and their choice. The radio frequency link and range precision is analyzed and calculated in detail. The theory calculation results and several factors which affect range precision are also discussed. In this paper electromagnetism compatibility and the methods to avoid it are proposed. The AGC technology in the radio frequency channel is also studied. In addition the duplex system, antenna and feeder line are discussed. The first channel of the anti-collision radar system is a typical C frequency band wireless communication transmitting and receiving channel. It can be applied to the considerable communication and measurement&control system. The second channel is a transponder with no guard. It can be used in the relay communication system and can be composed into a data platform with remote control if additional terminal equipment is added. Its application in other systems is also discussed.Finally the main parameters of the radio frequency channel are tested and the results are given. According to the results, the paper puts forward the improving opinion and measure for the expressway automobile anti-collision radar. Finally we make outlook for the progress of the more advanced automobile anti-collision radar.更多还原