Design And Realization Of C Band Linear FMCW Rader

In recent years,with the development of continuous radar technology,radar system has become an indispensable part of navigation and positioning,and derived different radar systems according to the different applications.Frequency modulated continuous wave(FMCW)radar has been widely used because of its simple structure,small volume,light weight,low power consumption,ignoring the range blind zones,high resolution,and easy integration.In the modern tanks war on the ground,the FMCW radar can quickly detect enemy’s close-in targets so that it is an important part in attacking.This thesis proposes the design and implementation of a C band(5.7GHz-5.9GHz)with a 200 MHz bandwidth of linear FMCW radar.The entire RF front-end system has been divided into three parts: the frequency synthesis module,the transmitter and receiver.The frequency synthesizer module design has been divided into three parts: the design of 1GHz clock signal for the DDS chip;the design of 4.1GHz local oscillator for transmitter;100MHz-112.5MHz continuous wave produced by DDS chip.In this part design,this paper introduces the principle of direct digital frequency synthesis(DDS)and phase-locked loop(PLL).In the design of the transmitter,the paper firstly analyzes measurement range of distance and range resolution,then introduces how the transmitter uses the technology of 16 times doubling to extend the band and produce a 1600MHz~1800MHz continuous wave.Then,with an up-conversion to make the linear continuous wave produce a C band Linear FMCW radar signal and send it out through a transmitting antenna.The receiver is a zero IF architecture.This paper illustrates the performance index and analyses the performance index of receiver,reasonably arrange the channel gain,designs the RF and IF digital control attenuator to improve dynamic range.At last,according to electromagnetic compatibility,the floorplan of entire system has been planned and designed the PCB.In the end of the paper,this project is summarized,and analyzed the problems.In the debugging process,put forward the solution,make the system meet the requirements of technical indicator and work normal,finally,presents some advice for the next version.