Design of generalised sidelobe canceller-based adaptive wideband beamformer without pre-steering delays

摘要

Implementation errors of pre-steering (PS) delays lead to severe performance degradation in the generalised sidelobe canceller-based adaptive wideband beamformer (G-AWBF). Therefore, a G-AWBF without PS delays is proposed. To eliminate PS delays, the G-AWBF is designed in the linear space spanned by the generalised steering vector (GSV) which is defined as the Kronecker product of spatial and temporal steering vectors. Based on GSVs, the quiescent weight and blocking matrix are constructed to substitute PS delays. Compared with the conventional G-AWBF, due to the removal of PS delays, an improved signal to interference and noise ratio can be achieved with reduced system complexity. With less adaptive weights and various versions of unconstrained adaptive algorithms being applicable, the proposed G-AWBF outperforms the existing Frost-based AWBF without PS delays in terms of computational load and robustness. Numerical experiments illustrate the effectiveness and superiority of the proposed G-AWBF.