Gridless DOA Estimation With Multiple Frequencies

Direction-of-arrival (DOA) estimation is widely applied in acoustic source localization. A multi-frequency model suitable for characterizing the broadband structure signals. In this paper, continuous (gridless) DOA problem with multiple frequencies considered. This formulated as an atomic norm minimization (ANM) problem. The ANM equivalent to a semi-definite program (SDP) which can be solved by off-the-shelf SDP solver. dual certificate condition provided certify optimality of solution so that sources localized finding roots polynomial. We also construct polynomial satisfy and show such construction exists when amplitude has uniform magnitude. ANM, spatial aliasing DOAs at higher cause challenges. discuss issue extensively propose robust combat aliasing. Numerical results support our theoretical findings demonstrate effectiveness proposed method.