传统的自适应波束形成器对各类型的阵列误差较为敏感尤其是在较大的波达方向(Direction of Arrival,DOA)误差存在的情况下,阵列的输出信干噪比严重下降.为了解决这个问题,文中提出了一种新的具有自适应可调误差半径的鲁棒波束形成器.每...传统的自适应波束形成器对各类型的阵列误差较为敏感尤其是在较大的波达方向(Direction of Arrival,DOA)误差存在的情况下,阵列的输出信干噪比严重下降.为了解决这个问题,文中提出了一种新的具有自适应可调误差半径的鲁棒波束形成器.每一步迭代都是以经典的鲁棒Capon波束形成器为基础,且使用的误差不确定度都是依据子空间投影定理推导出的一个二次约束二次规划问题的最优解.由于估计出的导向矢量不确定度均小于传统自适应波束形成器中使用的误差量,因此,阵列的输出性能得以提高.此外,为了能够扩展算法的适用性,引入了可变椭圆不确定集来同时处理多重误差因素.最终的实验结果证明了算法的正确性和有效性.展开更多
An algorithm of broadband minimum variance distortionless response(MVDR) based on the frequency energy normalization is proposed.First,every narrowband frequency component of the broadband signal is normalized by the ...An algorithm of broadband minimum variance distortionless response(MVDR) based on the frequency energy normalization is proposed.First,every narrowband frequency component of the broadband signal is normalized by the total narrowband energy of all array elements,and the narrowband power is calculated by MVDR.Finally,final spatial energy spectrum can be obtained by averaging or summing all results of every narrowband frequency bin.Any prior-information about the noise or the signal is unnecessary for the proposed method in this paper.The processing gain of the proposed method compared to the conventional broadband MVDR can be obtained as long as the amplitude fluctuation of the array noise frequency spectrum is severer than that of the target signal.The validity of the method is validated by the optimal signal detection theory.Simulation and real data are used to validate the performance of the method.Analysis results show that about 4 dB processing gain compared to the general broadband MVDR can be reached by the proposed method.展开更多
文摘传统的自适应波束形成器对各类型的阵列误差较为敏感尤其是在较大的波达方向(Direction of Arrival,DOA)误差存在的情况下,阵列的输出信干噪比严重下降.为了解决这个问题,文中提出了一种新的具有自适应可调误差半径的鲁棒波束形成器.每一步迭代都是以经典的鲁棒Capon波束形成器为基础,且使用的误差不确定度都是依据子空间投影定理推导出的一个二次约束二次规划问题的最优解.由于估计出的导向矢量不确定度均小于传统自适应波束形成器中使用的误差量,因此,阵列的输出性能得以提高.此外,为了能够扩展算法的适用性,引入了可变椭圆不确定集来同时处理多重误差因素.最终的实验结果证明了算法的正确性和有效性.
基金Sponsored by New Century Excellent Talent Support Project (NCET-04-0545)
文摘An algorithm of broadband minimum variance distortionless response(MVDR) based on the frequency energy normalization is proposed.First,every narrowband frequency component of the broadband signal is normalized by the total narrowband energy of all array elements,and the narrowband power is calculated by MVDR.Finally,final spatial energy spectrum can be obtained by averaging or summing all results of every narrowband frequency bin.Any prior-information about the noise or the signal is unnecessary for the proposed method in this paper.The processing gain of the proposed method compared to the conventional broadband MVDR can be obtained as long as the amplitude fluctuation of the array noise frequency spectrum is severer than that of the target signal.The validity of the method is validated by the optimal signal detection theory.Simulation and real data are used to validate the performance of the method.Analysis results show that about 4 dB processing gain compared to the general broadband MVDR can be reached by the proposed method.