一种高效的实值权均匀圆阵去相干波束形成算法

Effective beamforming algorithm of decoherent signals with uniform circular arrays based on real weights

提出了一种未经相移只采用实值权的均匀圆阵的去相干波束形成算法。均匀圆阵在模式空间中被转换为一虚拟线阵,利用此虚拟线阵的特殊阵列模型结构可构造一特殊矩阵,使其秩只与信源个数有关。该特殊矩阵的虚部所张成的空间包含干扰信号子空间,所以得到干扰信号子空间的正交补空间。利用此干扰信号子空间的正交补空间可以构造出一实值权向量。该算法不需空间平滑就可以抑制相干干扰,较传统的空间平滑算法具有更小的计算量,且在小快拍数下就能收敛且性能稳定。仿真结果显示出算法的有效性。

An adaptive beamformer of decoherent signals for uniform circular arrays is proposed that uses real weights only without phase shift. The uniform circular arrays are transformed into virtual uniform linear arrays in mode space. By exploiting the property of the virtual uniform linear arrays, a special matrix can be con- structed, whose rank is related to the number of signals. The interference subspace is contained in a subspace obtained using only the imaginary part of the special matrix, then a real weight vector can be constructed with the orthogonal complement of that subspace. The interferences can be suppressed without spatial smoothing, therefore the computation complexity is reduced. The rapid convergence and stable performance in finite snapshots of the proposed algorithm is demonstrated by numerical simulations.