Kinyili, MusyokaKitavi, Dominic MakaaNgari, Cyrus Gitonga2022-02-042022-02-042019-05-2532(3): 1-20, 2019; Article no.JAMCS.47041DOI: 10.9734/JAMCS/2019/v32i330148http://repository.embuni.ac.ke/handle/embuni/3961ArticleThis paper proposes a new sensor-array geometry (the 2-circle concentric array geometry), that maximizes the array’s spatial aperture mainly for bivariate azimuth-polar resolution of direction-of-arrival estimation problem. The proposed geometry provides almost invariant azimuth angle coverage and offers the advantage of full rotational symmetry (circular invariance) while maintaining an inter-sensor spacing of only an half wavelength (for non-ambiguity with respect to the Cartesian direction cosines). A better-accurate performance in direction finding of the proposed array grid over a single ring array geometry termed as uniform circular array (UCA) is hereby analytically verified via Cram´er-Rao bound analysis. Further, the authors demonstrate that the proposed sensor-array geometry has better estimation accuracy than a single ring array.enAntenna arraysArray signal processingDirection-of-arrival estimationParameter estimationPlanar circular arraysArticle