The effect of system mismatches on an adaptive linear constrained generalized sidelobe canceller (LC-GSC) is discussed in this paper. Based on the array gain index, two classic system mismatches, the direction of ar...The effect of system mismatches on an adaptive linear constrained generalized sidelobe canceller (LC-GSC) is discussed in this paper. Based on the array gain index, two classic system mismatches, the direction of arrival (DOA) mismatch and the mismatches arising from array disturbance, are studied, respectively. To obtain the effective methods for compensating for the system mismatches, we analyze the performance of the improved LC-GSC with the diagonal loading and additional constraints (such as the directional constraints and derivative constraints). The computer simulations show that the techniques of diagonal loading and additional constraints can effectively compensate for the system mismatches. The loss of array gains can be controlled within 3 dB in the presence of 20% of array disturbances or DOA mismatch when the signal-to-noise ratio is less than 10 dB. The analysis illustrates that the proposed compensation methods are valid and feasible.展开更多
This paper presents the performance analysis of the MUSIC algorithm in the presence of channel amplitude and phase Error. Theoretical expression for the error of DOA estimating with MUSIC algorithm and Cramer-Rao boun...This paper presents the performance analysis of the MUSIC algorithm in the presence of channel amplitude and phase Error. Theoretical expression for the error of DOA estimating with MUSIC algorithm and Cramer-Rao bound are derived. It is compared with simulations performed for some representative cases. The results of theoretical expression and simulation show that existence of these errors will increase the error of DOA estimating and degrade its performance.展开更多
针对空时互质采样下频率和波达方向(DOA,direction-of-arrival)稀疏联合估计中存在的二维栅格失配问题,提出一种栅格失配目标下的频率和DOA联合估计方法。首先对入射信号做空时互质采样,建立虚拟满阵下的二维稀疏恢复模型,然后在以上模...针对空时互质采样下频率和波达方向(DOA,direction-of-arrival)稀疏联合估计中存在的二维栅格失配问题,提出一种栅格失配目标下的频率和DOA联合估计方法。首先对入射信号做空时互质采样,建立虚拟满阵下的二维稀疏恢复模型,然后在以上模型中引入频率栅格失配误差项和角度栅格失配误差项进行二维修正,并给出一种改进的贪婪算法,通过对谱泄露变量联合求解来得到二维栅格失配误差项,最终将栅格失配目标校正到精确位置上。该方法不仅可以提高空频域上的自由度(DOF,degrees of freedom),而且在降低运算量的同时改善了频率和DOA联合估计的精度。仿真结果验证了方法的正确性。展开更多
基金supported by the Aviation Science Foundation of China under Grant No. 20112080014
文摘The effect of system mismatches on an adaptive linear constrained generalized sidelobe canceller (LC-GSC) is discussed in this paper. Based on the array gain index, two classic system mismatches, the direction of arrival (DOA) mismatch and the mismatches arising from array disturbance, are studied, respectively. To obtain the effective methods for compensating for the system mismatches, we analyze the performance of the improved LC-GSC with the diagonal loading and additional constraints (such as the directional constraints and derivative constraints). The computer simulations show that the techniques of diagonal loading and additional constraints can effectively compensate for the system mismatches. The loss of array gains can be controlled within 3 dB in the presence of 20% of array disturbances or DOA mismatch when the signal-to-noise ratio is less than 10 dB. The analysis illustrates that the proposed compensation methods are valid and feasible.
文摘This paper presents the performance analysis of the MUSIC algorithm in the presence of channel amplitude and phase Error. Theoretical expression for the error of DOA estimating with MUSIC algorithm and Cramer-Rao bound are derived. It is compared with simulations performed for some representative cases. The results of theoretical expression and simulation show that existence of these errors will increase the error of DOA estimating and degrade its performance.
文摘针对空时互质采样下频率和波达方向(DOA,direction-of-arrival)稀疏联合估计中存在的二维栅格失配问题,提出一种栅格失配目标下的频率和DOA联合估计方法。首先对入射信号做空时互质采样,建立虚拟满阵下的二维稀疏恢复模型,然后在以上模型中引入频率栅格失配误差项和角度栅格失配误差项进行二维修正,并给出一种改进的贪婪算法,通过对谱泄露变量联合求解来得到二维栅格失配误差项,最终将栅格失配目标校正到精确位置上。该方法不仅可以提高空频域上的自由度(DOF,degrees of freedom),而且在降低运算量的同时改善了频率和DOA联合估计的精度。仿真结果验证了方法的正确性。