Research On Spatial Power Combination Based On Sparse Antenna Arrays

Under the framework of modern communication,people need higher wireless signal transmission rate and better signal quality.Traditional radar detection systems mostly use a uniform array structure,and their lower angular resolution and smaller array aperture are increasingly unable to meet the current development needs of wireless signal transmission technology.Contrasted with the uniform full-array radar,the sparse array radar has a larger array aperture,higher detection accuracy and more flexible array design under the same number of array elements.However,the current research on the sparse array only stays in at the plane phased array level,there is still a lack of research on the sparse technology of frequency diverse arrays and other geometric arrays.In the traditional antenna field,the beam pointing control of electromagnetic waves mainly depends on the antenna pattern.This method requires a specific structural design in a specific environment,and lacks flexibility.Therefore,based on the characteristics of the frequency diverse array,this article will study its spatial power synthesis under the sparse technology.Based on the TR technology,study its free-space single-point energy focusing under the sparse technology.The major research contains three divisions:First,based on the antenna array synthesis principle,frequency diverse array characteristics and sparse array genetic algorithm,a new linear symmetric sparse frequency diverse array is proposed,and the power synthesis in two-dimensional space is analyzed using this array.Secondly,based on the above principles,three sparse frequency-controlled arrays with different array element distribution methods are proposed,and their spatial power synthesis in a hemispherical umbrella-shaped area with a radius of 60 km is simulated and analyzed.Focusing on the analysis of the energy focusing thickness at its apex,it can be concluded that three sparse frequency control array design schemes can achieve energy focusing thickness of 5-6km at a distance of 60 km.Through further analysis and comparison,the 8-sparse sub-array model and the 16-sparse sub-array model have better spatial power synthesis in this area.Using the simplest Dolph-Chebyshev synthesis method,analyzing the amplitude distribution of the three sparse frequency control array model arrays before and after synthesis optimization,it can be concluded that the optimized 8-sparse sub-array model has the best spatial power synthesis effect.Finally,build a single-point focusing model in free space based on the principle of time reversal of electromagnetic waves,and the influence of different parameters on the power synthesis in two-dimensional space is analyzed.On the basis of this model,two models of annular sparse time reversal mirror and grid-shaped sparse time reversal mirror are further proposed to analyze the influence of different parameters on the spatial power synthesis when the focus point is inside and outside the array.In addition,the sparse array technology is combined with the visual simulation software System Vue to design a system with controllable sparse array unit coordinates.This system can maintain the beam directivity of the main axis while increasing the sparse array sparse rate and the array gain is maintained at about 21.75 d B.