Channel Analyse Of Expressway Automobile Anti-collision Radar

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.