摘要
智能天线利用波束成形可有效接收目标信号并抑制干扰。当天线阵元数过多时,传统波束成形算法直接处理所有天线阵元的接收数据,导致计算复杂度大和收敛速度慢,无法实时有效地接收目标信号。为降低计算复杂度,提高收敛速度,提出一种降秩自适应波束成形算法,用于低复杂度的智能天线目标信号接收。所提算法基于随机梯度法,运用联合迭代优化对信号降秩,并使权重向量和投影矩阵相互迭代达到收敛。同时集员方法实现数据选择性更新,改进步长,提高收敛速度。并进行计算复杂度和收敛性能分析。仿真结果表明,相对其它随机梯度法,所提算法的输出性能更好,保持较低的更新比率。所提算法加快收敛速度,降低计算复杂度,保证接收目标信号精度。
Using beamforming, the smart antenna can effectively receive target signal and suppress interference. When the filter length is too much, traditional beamforming directly handles receiving data of all antenna arrays. It makes slow convergence and high complexity, which cannot receive target signal in real time. To reduce the complexity and speed up the convergence, a reduced-rank adaptive beamforming algorithm is proposed for the low-complexity reception of smart antenna target signal. Based the stochastic gradient, the proposed algorithm uses the joint iterative optimization to reduce the rank and obtain the weight vector and the projection matrix which are optimized to the convergence. Meanwhile, the set-membership realizes the data-selective updating and improves the step size to exhibit fast convergence. The computational complexity and convergence performance of the proposed algorithm are also analyzed. The simulations show the array output signal to output performance of the proposed algorithm is better than that of the other stochastic gradient algorithms, and the proposed algorithm keeps a low update rate and has the fast convergence rate and reduces the complexity with guaranteeing the accuracy of target signal reception.
引文
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