volume | PIER Journals

Abstract

To address the aperture fill time problem in broadband arrays, this paper proposes an efficient delay compensation algorithm based on a variable fractional delay (VFD) filter with high numerical stability. A low-complexity Newton structure is introduced into the VFD Lagrange interpolation algorithm; in addition, the numerical stability is significantly enhanced by centrally offsetting the element delay parameters and avoiding the explicit inversion of the transformation matrix. Subsequently, the robust Newton-VFD is applied to the implementation of the broadband array aperture fill time correction algorithm. The algorithm utilizes a cascaded architecture consisting of coarse integer-delay compensation and fine fractional-delay correction via the Newton-VFD. Simulation results demonstrate that the proposed low-complexity Newton-VFD significantly reduces hardware complexity while maintaining excellent magnitude-frequency characteristics, which enables efficient and high-precision correction of broadband array aperture fill time.

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Dr. Yufan Wang

Prof. Mingwei Shen

Dr. Zixuan Wang

Professor Guodong Han