The Development And Design Of Anti-collision Radar Signal Source For Trains

The researching of Anti-collision radar has been one of the popular field in theworld. But most of the current anti-collision radars are designed for cars. Theanti-collision radar can effectively prevent the collision between cars, thus decrease therate of traffic accidents. But, it’s always necessary to develop an efficient and reliableanti-collision radar that can discover threatening objects in advance in consideration ofthat the amounts of accidents happen between trains are not small and always lead to aheavy casualties.The LFMCW (Linear Frequency Modulate Continue Wave) signal is widely usedin many kinds of radar systems due to it’s good solution of range and speed。The maincontent of my subjects is to produce two sampled data stream of base-band signal(LFMCW)by using XC4VSX25, then the DUC chip-AD9957up-convert the base-banddata and finally output the analog LFMCW signal at intermediate frequency band（75MHz~125MHz）。The two signals will connect to the IF input port of transmitterand receiver respectively after the amplifiers and filters.In addition, the circuit boardsupplies a synchronizing pulse to AD circuit board and switching signals to transmittingantenna and receiving antenna. The external main processer can control FPGA、AD9957by the bus interface，thus can change the parameter of LFMCW signals。This passage mainly tells the design principle of the radar signal generating circuitboard, including the design of MCU and FPGA，the design of DUC circuit andsynchronous circuit of AD9957,the design of power system and amplifier circuit. Andthen records the results of debugging this signal generating circuit board combine withtransmitter and receiver, which explain the performance of the front end in the wholeanti-collision radar system.