Hourglass Arrays and Other Novel 2-D Sparse Arrays With Reduced Mutual Coupling

Authors:
Top Cited Papers
Open Access
Publisher website
Google Scholar
Abstract
Linear [one-dimensional (1-D)] sparse arrays such as nested arrays and minimum redundancy arrays have hole-free difference coarrays with O(N 2 ) virtual sensor elements, where N is the number of physical sensors. The hole-free property makes it easier to perform beamforming and DOA estimation in the coarray domain which behaves like an uniform linear array. The O(N 2 ) property implies that O(N 2 ) uncorrelated sources can be identified. For the 2-D case, planar sparse arrays with hole-free coarrays having O(N 2 ) elements have also been known for a long time. These include billboard arrays, open box arrays (OBA), and 2-D nested arrays. Their merits are similar to those of the 1-D sparse arrays mentioned above, although identifiability claims regarding O(N 2 ) sources have to be handled with more care in 2-D. This paper introduces new planar sparse arrays with hole-free coarrays having O(N 2 ) elements just like the OBA, with the additional property that the number of sensor pairs with small spacings such as λ/2 decreases, reducing the effect of mutual coupling. The new arrays include half-open box arrays, half-open box arrays with two layers, and hourglass arrays. Among these, simulations show that hourglass arrays have the best estimation performance in presence of mutual coupling.
Funding Information
  • ONR (N00014-15-1-2118)
  • California Institute of Technology
  • Taiwan/Caltech Ministry of Education Fellowship

This publication has 27 references indexed in Scilit: