Sparsity‐optimised farrow structure variable fractional delay filter for wideband array

Abstract In this paper, a new sparsity‐optimised Farrow structure variable fractional delay (SFS‐VFD) filter is proposed to address the aperture effect in wideband array. Our method based on coefficient (anti‐)symmetry and optimises number orders of its sub‐filters, greatly reducing non‐zero coefficients. The established cost function formulated as parametric minimisation problem with multiple regularisation constraints, solved by modified three‐block alternating direction multiplier (MTB‐ADMM), which improved introducing core correction items ensure stable fast convergence. Experimental results show that SFS‐VFD reduces complexity system decreasing use multipliers adders while ensuring high accuracy. array, effectively corrects achieves precise beam pointing.