Generalized Hole-Filling Strategy for Overlapping Hole-Existing Coprime Arrays for DOA Estimation
Xiang Li, Feng‐Gang Yan, Ming Jin, Maria Greco, Fulvio Gini · 2024
The holes in difference coarrays (DCA) of coprime arrays (CA) limit the extension of the aperture thus causing the waste of resources. In this paper, we propose a generalized hole-filling strategy for hole-existing CAs with overlapping subarrays, which allows to extend the aperture completely and achieves a larger hole-free DCA. First, we summarize a generalized CA configuration based on the existing CAs with overlapping subarrays and derive the symmetric relationship between holes and non-consecutive lags in DCA. Then, we propose a hole-free coprime array by arranging a third subarray outside the original configurations, where the first element location is determined by the symmetric relationship. Furthermore, we derive the optimal parameters that produce the largest hole-free DCA with a given number of sensors. Theoretical derivations and simulations are provided to demonstrate that the proposed hole-free coprime configurations overcome the original coprime arrays in terms of uniform degrees of freedom and direction-of-arrival estimation performance.