Design And Hardware Implementation Of Portable FMCW Radar System

Compared with pulse radar,FMCW radar has the characteristics of low cost,high precision,small size,and no blind spot distance measurement.FMCW radar is superior to radars of other systems in high-precision distance measurement.In addition to traditional precision-guided weapon systems in the military,FMCW radars mainly focus on "low,slow,and small" target monitoring on sea surface.The "low,slow,and small" target has the characteristics of slow speed,low height,small cross-sectional area of the radar,and insignificant acoustic and optical characteristics.Miniaturized,low-cost,portable FMCW radar systems have broad application prospects in civilian applications such as traffic control and detection,automobile collision avoidance systems,weather monitoring,drones,and security protection.This dissertation uses the working principle of FMCW radar to design a portable FMCW radar system from the perspective of miniaturization and low cost.Then we tested each hardware module and system.Our work is as follows:Firstly,this paper introduces the composition of FMCW radar system and the principle of distance measurement and velocity measurement.Then,this article compares the advantages and disadvantages of several major methods of FMCW radar frequency synthesis.Secondly,this article identifies the solutions adopted by portable FMCW radar system transmitters and receivers.The portable FMCW radar system transmitter uses a PLL structure that is easy to adjust and has a balanced overall performance.FMCW radar system receivers use a zero-IF architecture that avoids the appearance of image frequencies,making the overall structure of the receiver simpler.Thirdly,the hardware of each part of the transmitter and receiver is simulated and designed.Then,the digital portion and the RF portion were integrated together to make a PCB layout,and a separate test of the transmitter and the receiver was completed.Finally,the design and fabrication of the waveguide antenna were completed.The FMCW radar system was tested by distance measurement and speed measurement.The test results show that the radar system is working normally,but there is still much room for improvement in distance resolution and speed resolution.