E-band Low Sidelobe Array Antenna

As the eyes and ears to discover and understand the world,radar is widely used in navigation,speed measurement,meteorology,space remote sensing and a series of applications.In recent years,thanks to the progress of semiconductor technology and the development of millimeter wave technology,the demand for millimeter wave radar has been growing rapidly,compared with low-frequency microwave frequency bands such as centimeter wave,millimeter wave has higher frequency,shorter wavelength,smaller system components(such as antenna),higher integration and higher resolution;Compared with laser and infrared,millimeter wave can easily penetrate particles such as smoke,dust and fog,so it can work all day.Antenna is the core component of radar system,its structure is various,and its performance is very important to the whole radar system,which has always been the research hotspot and difficulty.In the millimeter wave band,waveguide slot array antenna has the advantages of simple and compact structure,small size,low sidelobe level and high aperture efficiency.It is easy to achieve high gain,high anti-jamming ability and high directionality.It has become the first choice in many communication systems and radar systems.In this paper,an E-band(60-90GHz)low sidelobe waveguide slot array antenna is designed.The working frequency is 71-86 ghz,and the number of array elements is 8×8;The side lobes of E and H planes can be controlled independently;Through the MATLAB analysis program of Chebyshev synthesis method and Taylor synthesis method,the comprehensive pattern is compared to obtain the excitation amplitude distribution of array antenna elements;the waveguide power division feed network is optimized to achieve different power distribution.In the whole E-band frequency range,the return loss of the complete feed topology is better than 20 d B,and the transmission loss is 0.09 d B Within.The gain of the array antenna weighted by different excitation amplitude is higher than 32 d Bi,the average side lobe of E-plane and H-plane is less than-20 d B,and the width of the main lobe is within ± 2.2 °.Good side lobe suppression is achieved and the overall performance is good.