基于频域LMS的自适应波束形成算法  

Frequency Domain LMS Based Adaptive Beamforming Algorithm

作　　者：张小飞[1] 徐大专[1] 

机构地区：[1]南京航空航天大学,南京210016

出　　处：《中国空间科学技术》2005年第2期41-46,58,共7页Chinese Space Science and Technology

基　　金：江苏省自然科学基金(BK2003089);航空科学基金(03F52042)的资助

摘　　要：在分析传统自适应波束形成的基础上,提出了一种基于频域最小均方(LMS)的自适应波束形成算法。该算法先对输入信号进行FFT变换,再通过LMS算法实现了频域上自适应波束形成。FFT变换后信号为稀疏矩阵,自相关下降,LMS算法收敛速度提高;理论分析和仿真结果表明了该算法收敛速度较快、性能较好,且计算量较少,易于实时实现,而且文章提出的波束形成算法对相干信源具有鲁棒性。Frequency domain LMS based adaptive beamforming algorithm is presented in this paper. The received signal of array antennas is analyzed, which shows that different DOAs correspond to different frequency, and the received signal is the addition of different spatial frequency signals, Which is the foundation of frequency LMS beamformer. This novel adaptive beamforming algorithm uses FFT as the preprocessing, and uses LMS algorithm to implement adaptive beamforming in frequency domain. Fast fourier transformed signal has a better decorrelation and leads to better convergence of LMS. Theoretical analysis and simulations demonstrate that this algorithm converges faster than the conventional adaptive beamforming algorithm, and it has the better performance. And this algorithm is robust to coherence source. Finally the algorithm is less complex and can be implemented easily, and it can be used widely.

关 键 词：自适应波束形成算法 频域LMS FFT变换 收敛速度 LMS算法 最小均方 输入信号 算法实现 稀疏矩阵 仿真结果 实时实现 相干信源 自相关 计算量 鲁棒性 

分 类 号：TN821.91[电子电信—信息与通信工程] TN911.72