Fast Synthesis Algorithm For Large Scale Antenna Array And Multi-beam Antenna Array

The work of this paper is mainly divided into three aspects:1)fast synthesis of uniformly spaced circular array antennas,2)phase-only sparse synthesis of uniform planar array antennas,and 3)phase-only synthesis of dual-beam array antennas.An iterative segmented fast cyclic convolution algorithm is proposed for fast synthesis of uniformly spaced circular array antennas.Firstly,the formula of the far-field pattern of the antenna array with uniformly spaced circularity,which cannot be directly expressed by traditional methods such as Fourier transform,is rewritten into a formula that can be calculated by cyclic convolution by changing the sampling.However,such an operation introduces the problem of insufficient sampling density.Therefore,through the auxiliary formula proposed in this paper,the rewritten formula is rewritten again to make it meet the required sampling density in the sampling.Finally,according to the fast convolution theorem,the fast Fourier transform is used to accelerate the calculation process.In the research of phase-only sparse synthesis of uniform planar array antennas,an improvement is made to solve the problems existing in the traditional iterative fast Fourier transform method.Firstly,the concept of rejection index is introduced and the strategy of gradual rejection is adopted to make the process of sparse synthesis more stable and reasonable and avoid falling into the situation of local optimal solution after several iterations as much as possible.Secondly,through the discussion of data domain,the method can consider the influence of scan constraints at the same time.In the research of phase-only synthesis of double beam array antenna,a phase-only synthesis method of double beam array with beam pointing calibration is proposed.The traditional iterative fast Fourier method is completely unable to synthesize the dual beam array antenna directly.Therefore,we have improved the traditional method.Firstly,the initial excitation is optimized,and the initial excitation is determined by amplitude and phase optimization.Secondly,the main lobe beam pointing is not accurate in the synthesis process to improve the problem.Based on the inspiration of Schelkunoff’s unit circle method,the two beams were divided and adjusted respectively,then the excitation was deduced,and then the synthesis was carried out by substituting back to the original synthesis process.Finally,some completely distorted patterns are discarded to make the synthetic pattern meet the constraint conditions.