为了充分利用非圆信号共轭相关不为零的特性,提高空间到达角(direction of arrival,DOA)和极化参数估计精度,提出了一种信号DOA和极化参数估计的稳健算法.即构造2个非圆信号的4阶累积量矩阵,引入旋转不变子空间(estimation of signal pa...为了充分利用非圆信号共轭相关不为零的特性,提高空间到达角(direction of arrival,DOA)和极化参数估计精度,提出了一种信号DOA和极化参数估计的稳健算法.即构造2个非圆信号的4阶累积量矩阵,引入旋转不变子空间(estimation of signal parameters via rotational invariance techniques,ESPRIT)算法思想,利用这2个矩阵之间的旋转不变特性求出旋转因子,实现信号DOA和极化参数更精确估计.与2阶相域ESPRIT相比,改进的算法适用于任意极化状态的信号,提高估计信号的利用率,同时利用4阶累积量对高斯噪声的抑制性处理相关噪声,使估计信号的精度有了明显提升,并通过仿真结果验证了改进算法的有效性.展开更多
In order to increase the coupling efficiency and suppress the random angular jitter induced by atmosphere turbulent, the fine tracking system with fast steering mirror （FSM） is demonstrated. The field experiment res...In order to increase the coupling efficiency and suppress the random angular jitter induced by atmosphere turbulent, the fine tracking system with fast steering mirror （FSM） is demonstrated. The field experiment results of free-space optical communication link across 16 km show that when there is no tracking, the range of the x-axis coordinates＇ fluctuation achieves 46 pixels, corresponding to the incident angle of 73.6 μrad, and its mean square deviation is 6.5 pixels, corre- sponding to the incident angle of 10.4/.trad. When there is tracking, the range of fiuctuation is suppressed to 10 pixels and 16 ktrad, and the mean square deviation reduces to 1.5 pixels and 2.6 brad for the spot＇s centroid and the incident angle, respectively. Significantly, the coupling efficiency increases by 6 times, and the fluctuation of received light power decreases obviously.展开更多
文摘为了充分利用非圆信号共轭相关不为零的特性,提高空间到达角(direction of arrival,DOA)和极化参数估计精度,提出了一种信号DOA和极化参数估计的稳健算法.即构造2个非圆信号的4阶累积量矩阵,引入旋转不变子空间(estimation of signal parameters via rotational invariance techniques,ESPRIT)算法思想,利用这2个矩阵之间的旋转不变特性求出旋转因子,实现信号DOA和极化参数更精确估计.与2阶相域ESPRIT相比,改进的算法适用于任意极化状态的信号,提高估计信号的利用率,同时利用4阶累积量对高斯噪声的抑制性处理相关噪声,使估计信号的精度有了明显提升,并通过仿真结果验证了改进算法的有效性.
基金supported by the Hubei Provincial Department of Education Grant(Nos.CXY2009B032andD20102506)
文摘In order to increase the coupling efficiency and suppress the random angular jitter induced by atmosphere turbulent, the fine tracking system with fast steering mirror （FSM） is demonstrated. The field experiment results of free-space optical communication link across 16 km show that when there is no tracking, the range of the x-axis coordinates＇ fluctuation achieves 46 pixels, corresponding to the incident angle of 73.6 μrad, and its mean square deviation is 6.5 pixels, corre- sponding to the incident angle of 10.4/.trad. When there is tracking, the range of fiuctuation is suppressed to 10 pixels and 16 ktrad, and the mean square deviation reduces to 1.5 pixels and 2.6 brad for the spot＇s centroid and the incident angle, respectively. Significantly, the coupling efficiency increases by 6 times, and the fluctuation of received light power decreases obviously.
