Angular information resolution from co-prime arrays in radar

Abstract

Angular resolution can be improved by using co-prime arrays instead of uniform linear arrays (ULA) with the same number of elements. We investigate how the possible co-prime angle resolution is related to the angle resolution from a full ULA of the size equal to the virtual size of co-prime arrays. We take into account not only the resulting beam width but also the fact that fewer measurements are acquired by co-prime arrays. This fact is especially relevant in compressive acquisition typical for compressive sensing. This angular resolution is called angular information resolution as it is computed from the intrinsic geometrical structure of data models that is characterized by the Fisher information. Based on this information-geometry approach, we compare angular information resolution from co-prime arrays and from the two ULAs. This novel resolution analysis is applied in a one-dimensional azimuth case. Numerical results demonstrate the suitability in radar-resolution analysis.