Improved Uniform Linear Array Fitting Scheme With Increased Lower Bound on Uniform Degrees of Freedom for DOA Estimation

Recently, uniform linear array (ULA) fitting (UF) principle is proposed for sparse (SA) design using pseudo-polynomial equations. Typically, it verified that the designed SAs via UF enjoy a lower bound on degrees of freedom (uDOF), which approximately 0.5 N 2 with sensors. Herein, an improved (IUF) scheme to significantly increase uDOF, realized by introducing two sub-ULAs, name adjoint transfer arrays (ATAs), both sides sub-ULA. The ATAs together sub-ULA serve as new layer construct (ATL) has aperture in comparison traditional improve derived detail. Furthermore, novel are developed based ATL verify effectiveness IUF uDOF. Numerical simulations superiority devised direction-of-arrival (DOA) estimations.