Direction-of-arrival estimation via concentric circular antenna arrays

Abstract

The estimation of direction-of-arrival (DOA) of source signals has been well-studied research area in both military and civil applications. The MUSIC (Multiple SIgnal Classification) algorithm based on the signal subspace separation idea has already been investigated and employed for uniform linear arrays (ULA) and uniform circular arrays (UCA) in DOA estimation extensively. However, an important disadvantage of the ULA geometry in DOA estimation is that it can only estimate the azimuth angle. To estimate the elevation angle, UCA geometries are employed in many applications. As the concentric circular arrays (CCA) that are discussed in this paper have better angle resolutions compared to ULAs, and as they require smaller physical area compared to UCAs with the same number of array elements, CCAs are proposed to be used in mobile applications as a preferable alternative. The DOA estimation problem for CCAs is defined and the steering matrix is expressed in this paper, moreover the performance analysis is investigated by simulations.