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提出了一种新型的基于幅度分档的赋形波束方向图综合算法.该算法共分为3步.首先,使用传统方向图综合方法如交替投影得到波束的无幅值限制的阵元激励;然后,使用概率密度理论对得到的阵元激励幅度进行处理得到量化的阵元激励幅度,最后,通过量化阵元激励幅度,使用半正定松弛(SDR)方法得到阵元激励的相位分布.上述步骤中,如何使用概率密度理论得到量化的阵元激励幅度是3步中较为重要的一步.将阵元激励幅度用概率密度变量进行替代,通过事先设定的阵元激励幅度档位个数,以及每个阵元激励幅度落在相应档位时取值的概率,可以得到含有概率密度变量的综合方向图表达式.最小化含有概率密度变量的综合方向图与理想方向图的功率之差即可得到量化的阵元激励幅度.使用概率密度理论得到量化阵元激励幅度的优势在于,可以根据任意形状的阵面和阵元栅格排布来划分幅度的档位区间,从而有着更广泛的适用性.在例证部分,通过多组算例的仿真,以及与一些对算法性能的分析,所提算法验证了其在综合效果上的优越性.“,”In this paper,a novel algorithm for shaped-beam pattern synthesis is proposed based on quantization of element excitation amplitude.The algorithm is divided into three steps.First,traditional pattern synthesis,such as alternative projection,is performed to obtain the element excitation of the beam without amplitude constraints.Second,the probability density method is used to acquire the quantized amplitude of element excitations.Finally,the Semi-Definite Relaxation (SDR) method is employed to obtain the element excitation phase of each beam.In the above procedures,how to use the probability density method to obtain the quantized amplitude of the element excitation is the most important step.Each element excitation amplitude is replaced by the probability density variable.By setting the element excitation amplitude levels in advance and the probability of each element excitation amplitude when falling in the corresponding level,the probability density pattern is obtained.The difference between the probability density pattern and the ideal pattern is then minimized to acquire the quantized element excitation amplitude.The probability density method has the advantages in that the quantization levels can be acquired through footprints and arrays with arbitrary shapes,and hence can be applied in a wider background.Simulation verifies the superiority of the proposed algorithm.