摘要
针对现有分布式目标天线接收功率优化求解运算量偏大、不易编程实现等不足,本文提出了一种基于"三步"解耦思想的分布式目标最优极化求解新方法。考虑到分布式目标的散射回波多为部分极化,文中首先讨论了部分极化波的天线最优接收,得到了部分极化波的天线接收失匹配条件及天线接收功率上下限,并给出了该上下限对应的发射天线最优极化数值求解。以此为基础,借鉴确定性目标"三步"解耦求解思路,给出了收发天线无约束情形的分布式目标最优极化求解具体步骤。算法关键是通过优化部分极化波天线失匹配接收条件下的天线接收功率得到发射天线最优极化,而不是通过优化目标散射回波功率得到。与现有算法相比,由于"三步"解耦思想简化了分布式目标天线接收功率优化求解,因而它较现有算法更具有实用性。旧金山地区的AIRSAR实测极化数据的实验结果验证了新方法的有效性。
The polarimetric received power optimization is an important study in radar polarimetry.Aiming at the deficiency of the present method for optimizing polarimetric received power,a new method is proposed for the partially polarized case referring to the three step procedure for the coherent case.Considering that the scattering waves of random targets are partially polarized,the receiving of partially polarized wave is discussed firstly,and then the mismatched/matched receiving conditions and their corresponding receiving powers are obtained.Based on these discussions,a three step procedure to polarimetric received power optimization is presented for the partially polarized case.The key step of the proposed method is also the calculation of the optimal polarization of transmitted antennas. However,the proposed one is different from the present one in calculating the optimal polarization states of transmitted antennas.And the transmitted optimal polarization states for the partially polarized case is obtained by optimizing polarimetric received power under the conditions of antenna mismatched/ matched receiving for partially polarized wave,not by optimizing the scattering wave power of random target.Another difference is the optimal polarization states corresponding to the maximum or minimum polarimetric received power can be obtained at the same time.Comparing with the present method for optimizing polarimetric received power,the new method is more applicable than the present method for optimizing polarimetric received power because the three step procedure is used to simplify the process of obtaining the optimal polarization states of random target.With the real polarimetric SAR data at the site of San Francisco, USA,we demonstrate that;a） the new method is validated;b） the new method is more efficient in calculating the optimal polarization states of the received and transmitted antennas than the present method.
出处
《信号处理》
CSCD
北大核心
2011年第1期55-59,共5页
Journal of Signal Processing
