Anti-Interference Research Of Vehicle-Mounted Millimeter Wave Radar Systems

The overall number of vehicles in our country has increased recently,along with the industry’s rapid development.The development of autonomous vehicle technology and advanced driver assistance system has also become a popular topic for industry practitioners and academics.The field of environmental observation greatly benefits from the high performance,all-weather,broad band,powerful penetration ability,and little weather impact of vehicle-mounted millimeter wave radar.The jamming issue that the vehicle-mounted millimeter wave radar is confronting is becoming more and more serious as it is used more and more frequently,which has significant implications for the study into its antijamming technology.This thesis suggests a frequency-division sub band anti-jamming technique to counteract the narrow-band interference of vehicle-mounted millimeter wave radar based on the operation of FMCW radar and by analyzing the signal transmission process of FMCW radar and starting from the radar transmitting source.By combining with a low-pass filter at the receiver end,the anti-jamming waveform successfully eliminates narrow-band interference in radar antijamming and randomizes the sub band of an otherwise broadband monotone,improving the recognition of individual radar waveforms.The algorithm’s efficacy is mathematically inferred,and through software modeling and actual testing,it is demonstrated that this approach performs well in environments with narrow-band interference.The wideband interference in the vehicle-borne FMCW radar reciprocal interference is suppressed using the signal reconstruction method based on the sub band waveform of frequency division and the Hilbert-Huang transform.Wideband interference sampling spots are precisely found using the Hilbert-Huang transform after an analysis of the FMCW radar’s wideband interference features,and the interfered signals are then recreated using various frequency sub bands with target reflection signals.The experiment confirms that the algorithm still performs well in the presence of multiple interference,greatly enhances the signal-to-noise ratio in the reconstruction of multiple interference signals and enables the next-generation CFAR algorithm to precisely localize the target and suppress the broadband interference.A model was created in the lab with an eye toward the real working setting of the millimeter-wave radar installed on the car.To model the narrow-band and wide-band interference of the vehicle-mounted radar in the working environment,multiple radars were used.As mentioned above,the FMCW radar’s anti-jamming model is created by naturally merging various FMCW radar anti-jamming techniques.The proposed antijamming model has been demonstrated through comparative tests to be capable of withstanding both narrowband interference and broadband interference in a complicated jamming environment.