Efficient Two-Stage Beampattern Synthesis Against Interference for Sparse Linear Array Design

In this letter, an efficient two-stage adaptive beamforming algorithm is proposed for sparse linear array synthesis. In the first stage, the unitary matrix pencil method is employed to synthesize a sparse linear array to generate a pattern with a low sidelobe level (SLL). Next, by serving the results obtained previously as a constraint, an adaptive beamforming method is implemented to enhance the anti-interference ability of the array while maintaining the shape of sparse patterns as much as possible. Moreover, an adjustable factor is introduced to enhance the capability of seeking feasible solutions, and new constraints are raised to broad nulls, respectively. Four numerical examples involving low SLL, single interferer, multiple interferers and broad nulls are provided to validate the flexibility and effectiveness of the proposed method. Simulation results show the superior anti-interference performance and high computational efficiency of the proposed algorithm.