DOA Estimation using Planar Sparse Fractal Array

Abstract

The term fractal refers to the fractional dimensions that have recursive nature and when clubbed with the properties of sparse arrays leads to the generation of a novel array called a sparse fractal array. In this paper, we extend our research to the 2D domain by introducing planar sparse arrays which generate hole-free difference coarray and have OpN2q elements just like the OBA but here in the new closed box form, with the additional property of fractal arrays along with sparseness. To estimate azimuth and elevation angle we have designed planar sparse fractal arrays using nested arrays and coprime arrays as the fundamental basic generating array which helps in achieving a high degree of freedom which makes it useful for DOA estimation. Simulations show that the proposed planar arrays have the better estimation performance when compared with existing planar arrays like URA, OBA, and CPA.