A novel probability-constrained approach to robust wideband beamforming with sensor delay lines

To improve robustness of the wideband beamformer against look direction error, a low computational complexity robust wideband beamforming algorithm with sensor delay lines (SDLs) is proposed by extending the narrowband robust beamforming method to the wideband case. Based on the SDL wideband model, this wideband beamforming optimizing formula originally consists of a group of probabilistic constraints imposed on the sampled frequency points and the coefficient vector constraint. By constraining the Euclidean distance between the response at reference frequency points and that at others over the angles of interest, these probabilistic constraints can be replaced by just one constraint on the reference frequency point and the computational complexity is reduced. The last optimizing formula can be solved with interior point method after being reformed to the second order cone programming (SOCP). The simulations illustrate the effectiveness of the proposed algorithm.