Improved Design Of Spaceborne L-Band Dual-Polarized Microstrip Antenna Array

With the rapid development and application of mobile communication technology,wireless communication system has long been popular to people in every corner of life,and its application and demand is more diverse.Space borne antenna is the throat of satellite communication.In face of the complex electromagnetic environment in space and the limited volume,space,weight on satellite,high performance satellite antenna is a good guarantee of satellite communication system performance.In particular,for a space borne expandable planar array antenna operating in the L-band,the cell size is limited by the free wavelengths in the space,and the number of elements is typically as many as several tens.optimizing the cell size,element spacing and array form to ensure that on the premise of electrical performance smaller volume,lighter weight is very important.In this paper,a crossed two-dimensional sparse antenna array is designed for the spaceborne integrated aperture microwave imaging radiometer based on the needs of high-precision ocean salinity satellite detection.A miniaturized dual polarized microstrip antenna unit is designed to provide a selectable scheme for weight loss design of the spaceborne antenna.This article has done the following work:1.According to the phenomenon of the serious distortion of the antenna pattern when the antenna array arrange in the middle of the star,the form of cross-shaped array was used.Two arms placed near the edge position of the star and the other two arms hanged in the air.The results of HFSS simulation analysis and measurement show that the arrangement of the array and the layout position greatly improve the antenna element pattern on the star,so that the electrical performance of each antenna element in the array can meet the design index,and the unit characteristic and unit consistency also achieve the design requirements.2.The simulation design of the miniaturized unit of dual polarized microstrip antenna is completed.The size of the miniaturization unit can be reduced to 71.40%,the voltage standing wave ratio is less than 1.25,the port isolation is greater than 45 d B,the cross polarization is less than-44.50 d B,and the beam width is greater than 85 degrees.Compared with the dual-polarized microstrip antenna unit without miniaturization,the simulation results of the miniaturized unit have little change and the expected design goal is achieved.3.The change of the pattern of the miniaturized antenna element in the straight arm array is analyzed.The change of the pattern of the elements in the array when the simulated star is loaded using the straight arm array of the miniaturization unit is also analyzed.According to the actual situation of the inconformity in the different polarization pattern of the antenna elements on the simulated star array,a groove structure is added to the array cavity,which can improve the consistency of the pattern effectively.Finally,the miniaturization unit is used to make the initial simulation.The simulation results show that the overall size is reduced,and the unit pattern in the array does not change greatly in the half power beam range,and the simulation results such as half power beam width and cross polarization meet the design index.The antenna array that using the miniaturization unit provides an solution to the weight loss design of the spaceborne antenna.