Development Of Key Components Of E-band Anti-collision Radar Front End

In recent years,the number of domestic vehicles is increasing rapidly,resulting in serious consequences of frequent traffic accidents,causing very serious casualties and economic losses.Anti-collision radar is an active safety anti-collision system installed on vehicles,which can effectively avoid traffic accidents and ensure the life safety of drivers.Compared with other frequency bands currently used by millimeter-wave anti-collision radars,E-band millimeter-wave anti-collision radars have many advantages,and are the future development direction of millimeter-wave anti-collision radars.In this thesis,some key components in the front end of E-band anti-collision radar system are developed.The main research work of the thesis is as follows.The antenna used for the E-band anti-collision radar is studied.First designed a 1×16unit series feed microstrip patch antenna.The current feed amplitude distribution of each patch radiating element in the linear array antenna is weighted according to the coefficient of the Dolph-Chebyshev polynomial,so that it has a higher gain and a lower side lobe level.Subsequently,the radiation unit of the antenna part was improved,and the slot loading unit was added to make it have a wider impedance matching bandwidth,so as to solve the limitation of the thin dielectric substrate on the impedance bandwidth of the microstrip antenna.The return loss of the antenna in the 76GHz-81GHz band is better than 10dB,the peak gain reaches 19.2dBi,and E-plane beam width is 5°.On this basis,a2×16 unit area array antenna fed by a U-shaped power divider is designed to increase the antenna gain,and the gain reaches 21.5dBi.Finally,a Multi-Input Multi-Output?MIMO?antenna array based on two 2×16 unit area array antennas and four 1×16 unit line array antennas was studied,and metallized through-hole grounding,Improve the isolation of sending and receiving.The sixth-order frequency doubling link used to double the Ku-band signal to the E-band signal is studied.The entire frequency doubling link includes the booster amplifier,the front-stage band-pass filter,the sixth-order frequency multiplier,and the post-stage band-pass filter.The pre-stage filter is designed based on the miniaturized hairpin lad-der impedance resonator,which reduces the volume.Optimize layout layout,introduce cross coupling,and bring transmission zero.And,the input and output adopts 0°feeding form,and another transmission zero point is added to the stop band of the filter.Finally the filter has four transmission zero points,which greatly improves the out-of-band suppres-sion.Based on the one-cavity multi-mode technology,the TE₂₀₁mode and TE₁₀₂mode are used to design the dual-mode post-band pass filter of the Substrate Integrated Waveguide?SIW?,and The number of resonant cavities is reduced.The test results of the two filters are in good agreement with the simulation results.They are respectively cascaded at the input and output ports of the sixth frequency multiplier,which can effectively improve the ability of the frequency multiplier to suppress other harmonics.The overall frequency doubler link test results show that,under the premise of a fixed input power of-7dBm,the output power of the frequency doubler link in the 76-81GHz range is greater than 10dBm,and the output power flatness is±0.3dBm.The simulation and test results show that the designed antenna for the E-band anti-collision radar and the sixth-order octave link have good performance,which lays the foun-dation for the development of a high-performance E-band millimeter-wave anti-collision machine system in the next stage.