基于广义旁瓣相消器的快速降秩自适应波束形成算法

A Fast Reduced-rank Adaptive Beamforming Based on Generalized Sidelobe Canceller

传统的基于广义旁瓣相消器(GSC)的降秩自适应波束形成算法,降秩矩阵大多数需要通过特征值分解获得,而特征值分解会带来新的大运算量,大大限制了算法的工程实现。提出了一种新的基于广义旁瓣相消器的快速降秩自适应波束形成算法(FRGSC)。该算法直接利用广义旁瓣相消器下支路的中间快拍数据来构造降秩矩阵,利用所有可以利用的快拍数(多于干扰个数的快拍数)来构造降秩矩阵。基于GSC的传统降秩算法构造降秩矩阵需要的运算量为O((N-1)3)(N为自适应自由度),而FRGSC算法构造降秩矩阵只需要一次复数乘法和少量复数加法,所需运算量大大降低。该方法在实际应用中具有更优的实时性,适用于大阵列连续波体制雷达。仿真结果证明了所提出的基于广义旁瓣相消器的快速降秩自适应波束形成算法具有很好的波束形成性能,验证了算法的有效性。

For most traditional reduced-rank adaptive beamforming algorithm based on Generalized Sidelobe Canceller （GSC）, the rank reducing matrix is achieved by eigendecomposition which brings the computational burden. To alleviate the computational burden and achieve real-time processing, a new fast reduced-rank adaptive beamforming algorithm based on GSC （FRGSC） is proposed. It uses a set of intermediate data vectors in the lower branch of GSC to construct the rank reducing matrix. Also, in order to achieve the robustness, all available snapshots have been used to obtain the rank reducing matrix. The computational burden to obtain the rank reducing matrix of the traditional reduced-rank beamforming algorithm based on GSC is on the order of O（（N-1）3）, while the FRGSC method needs only one complex multiplication and a little complex additions. The FRGSC method is very simple in design and programming. In practical application, this method has more excellent real-time responsibility, and it can be used to deal with the real-time adaptive array processing for continuous wave radar. The simulation results show that the fast reduced-rank adaptive beamforming algorithm has very good beamforming performance, and the validity of this new method is demonstrated.