| Intelligent automobile’s recognition of the surrounding environment is mostly achieved by the multi-sensor fusion.Millimeter wave radar,with its advantages of long distance,all-weather and low cost,is the best choice for intelligent vehicle in remote distance detection.In this paper,a radar signal processing system was designed based on K-MC3 24 GHz radar sensor.The purpose of the system is to realize the accurate calculation of the distance,velocity and direction of the object ahead of the radar.Firstly,this paper analyzed the functional requirements of the hardware circuit,and designed the overall structure of the corresponding hardware circuit.Then,the VCO was corrected by designing the corresponding modulation signal generation circuit.Next,a radar signal processing circuit was designed to process the radar output signal,and the circuit was simulated and verified.Finally,the circuit designed above was tested,and the results showed that the design in this paper effectively.Based on the analysis of the functional requirements of the algorithm,the overall algorithm structure of the system was designed.In order to filter out the high frequency interference signal,the low pass FIR filter was designed using MATLAB.Then,in order to identify the frequency of the target signal,an algorithm combining FFT with Chirp-z was designed.Finally,The CA-CFAR algorithm was designed to eliminate the environmental interference signal.And in order to solve the false alarm and missing alarm,the algorithm combined maximum amplitude similarity method and the modulation modulation signal frequency method was designed.In order to combine the hardware part and the software part,this paper designed the software structure of the system.Then this paper debugged the software of the system.And the CA-CFAR algorithm was modified according to the debugging results.The thresholds of the peak identification algorithm and the false target elimination algorithm was determined.Finally,the radar system was tested in single target and multiple target situations.The test results show that the system can accurately calculate the speed and distance information of the targets. |
