Research And Design Of X-ban Wave Gduide Slot Array Antenna With Low Side Lobe And High Gain

On the basis of reviewing the basic principle and development status of waveguide slot antenna,this paper studies and designs the waveguide slot antenna's function of realizing low sidelobe and high gain from two aspects of theoretical calculation and software simulation analysis.Based on the theoretical analysis of slot antenna in electromagnetic field,the opening mode of slot on waveguide is determined,the geometric size of slot and the distance between slots are calculated,and the slot width is optimized by HFSS electromagnetic field simulation software.Finally,through the application of Chebyshev polynomial in the distribution of antenna conductance,the conductance of waveguide with 10 slots is analyzed and calculated,and the offset of slots from the center of waveguide is calculated.Finally,the HFSS software is used to simulate the waveguide linear array antenna.The results show that the waveguide linear array antenna has the function of low sidelobe and high gain.Starting from the basis of waveguide slot linear array antenna,in order to further reduce the sidelobe and improve the antennaGain,8 linear array antennas are combined into an 8*10 matrix array antenna.A slot-coupled waveguide is designed,by which the 8 *10 matrix array antenna is fed centrally.The simulation results show that the maximum gain of waveguide planar array antenna at the main lobe is 22.3dBi,and the difference between the first side lobe and the main lobe is 17 dBi.When the antenna operates at 9.5 GHz to 9.72 GHz,the echo loss of the antenna is below-10 dBi,and at 9.6 GHz,the echo loss of the antenna reaches-58.8dBi,and the operating frequency band is 220 MHz.Compared with waveguide linear array antenna,the antenna achieves better low sidelobe and high gain function.Finally,in order to further reduce the sidelobe level and improve the gain of the antenna,starting from the theoretical method of adding angle reflector on both sides of the waveguide radiation slot,the angle and distance slot position of the angle reflector are optimized by the simulation software,and the best results are obtained.The experimental data show that the final antenna gain increases by 1.95 dBi,the sidelobe level decreases by about 1dBi,the voltage standing wave ratio decreases by 0.03,the echo loss decreases by 2.6dBi,and the bandwidth increases by 100 MHz to improve the low sidelobe and high gain performance of the antenna.A waveguide slot linear array antenna is fabricated.The measured results of its echo loss and VSWR by vector network analyzer are basically consistent with the simulation results.