Research On Characteristics And Optimization Methods Of Sparse Array

The antenna arrays have been widely used in satellite communications,biomedicine,electronic warfare and many other fields,because of their high gain,low sidelobe pattern,and they are easy to achieve beam scanning and special beamforming.In recent years,as people have increasingly higher requirements for the information processing capabilities and multi-band signal interception capabilities of the array antennas in radar systems and wireless communication systems,the exploration of optimized design methods is especially important to develop large-scale and wideband angles antenna arrays.However,uniform arrays with half-wavelength spacing have faced high cost,difficulty in heat dissipation,and the small spacing leads strong coupling.The sparse array synthesis method has become one of the key technology to reduce costs and increase the design freedom of software and hardware.Based on this background,this paper focuses on the integration of large-spacing constrain,wide-angle scanning,grating lobe suppression,and wide-band low-sidelobe sparse arrays.The main contents are as follows:Firstly,in view of the influence of the elements on the performance of the sparse array under a given aperture,based on the probability method,the performance of the sparse array and density sampling is studied,and the characteristics of the sparse array are summarized through calculation examples,which provides prior knowledge for the actual array synthesis problems.Secondly,in view of the large spacing wide-angle scanning,grating lobe suppression problem in the sparse array,based on genetic algorithm and particle swarm algorithm,adding the process of merging array elements,and a sparse array design method based on subarray synthesis design technology is proposed.And through the examples of the transceiver arrays in a given frequency,it is shown that the two algorithms can realize the rapid evaluation and low sidelobe synthesis of large-scale sparse arrays under the premise of ensuring the array performance,and solve the beam scanning problem under the large spacing constrain arrays.Finally,aiming at the problem of sparse array broadband low sidelobe synthesis,based on Schlottmann Tiling,a design scheme of aperiodic tiled antenna array that can suppress the grating lobes and achieve low sidelobe effects in the broadband is proposed.The scheme is based on a technology to increase the disturbance point,and combined with the EPSO optimization algorithm,the performance of this method is verified by the example of the area array and modular subarray splicing into a large-scale array.The optimized array ensures that the low-frequency and half-wavelength is the minimum array element spacing while the array can be arranged.There are no grating lobes in the bandwidth that meets the double frequency or even higher frequencies,and it can be scanned at any angle in the space.